Merge branch '4.6' of scm.dev.nokia.troll.no:qt/qt-s60-public into 4.6-integration

* '4.6' of scm.dev.nokia.troll.no:qt/qt-s60-public:
  QS60Style: QCalendarWidget draws only one-digit dates
  Add spectrum analyzer demo app

92 files changed, 13727 insertions, 0 deletions

diff --git a/demos/spectrum/README.txt b/demos/spectrum/README.txt
new file mode 100644
index 0000000..c39d4a7
--- /dev/null
+++ b/demos/spectrum/README.txt
@@ -0,0 +1,103 @@
+Spectrum analyser demo app
+==========================
+
+Introduction
+------------
+
+This application is a demo which uses the QtMultimedia APIs to capture and play back PCM audio.  While either recording or playback is ongoing, the application performs real-time level and frequency spectrum analysis, displaying the results in its main window.
+
+
+Acknowledgments
+---------------
+
+The application uses the FFTReal v2.00 library by Laurent de Soras to perform frequency analysis of the audio signal.  For further information, see the project home page:
+    http://ldesoras.free.fr/prod.html
+
+
+Quick start
+-----------
+
+Play generated tone
+1. Select 'Play generated tone' from the mode menu
+2. Ensure that the 'Frequency sweep' box is checked
+3. Press 'OK'
+4. Press the play button
+You should hear a rising tone, and see progressively higher frequencies indicated by the spectrograph.
+
+Record and playback
+1. Select 'Record and play back audio' from the mode menu
+2. Press the record button, and speak into the microphone
+3. Wait until the buffer is full (shown as a full blue bar in the top widget)
+4. Press play, and wait until playback of the buffer is complete
+
+Play file
+1. Select 'Play file' from the mode menu
+2. Select a WAV file
+3. Press the play button
+You should hear the first few seconds of the file being played.  The waveform, spectrograph and level meter should be updated as the file is played.
+
+
+Things to play with
+-------------------
+
+Try repeating the 'Play generated tone' sequence using different window functions.  These can be selected from the  settings dialog - launch it by pressing the spanner icon.  The window function is applied to the audio signal before performing the frequency analysis; different windows should have a visible effect on the resulting frequency spectrum.
+
+Try clicking on one of the spectrograph bars while the tone is being played.  The frequency range for that bar will be displayed at the top of the application window.
+
+
+Troubleshooting
+---------------
+
+If either recording or playback do not work, you may need to select a different input / output audio device.  This can be done in the settings dialog - launch it by pressing the spanner icon.
+
+If that doesn't work, there may be a problem either in the application or in Qt.  Report a bug in the usual way.
+
+
+Application interface
+---------------------
+
+The main window of the application contains the following widgets, starting at the top:
+
+Message box
+This shows various messages during execution, such as the current audio format.
+
+Progress bar / waveform display
+- While recording or playback is ongoing, the audio waveform is displayed, sliding from right to left.
+- Superimposed on the waveform, the amount of data currently in the buffer is showed as a blue bar.  When recording, this blue bar fills up from left to right; when playing, the bar gets consumed from left to right.
+- A green window shows which part of the buffer has most recently been analysed.  This window should be close to the 'leading edge' of recording or playback, i.e. the most recently recorded / played data, although it will lag slightly depending on the performance of the machine on which the application is running.
+
+Frequency spectrograph (on the left)
+The spectrograph shows 10 bars, each representing a frequency range.  The frequency range of each bar is displayed in the message box when the bar is clicked.  The height of the bar shows the maximum amplitude of freqencies within its range.
+
+Level meter (on the right)
+The current peak audio level is shown as a pink bar; the current RMS level is shown as a red bar.  The 'high water mark' during a recent period is shown as a thin red line.
+
+Button panel
+- The mode menu allows switching between the three operation modes - 'Play generated tone', 'Record and play back' and 'Play file'.
+- The record button starts or resumes audio capture from the current input device.
+- The pause button suspends either capture or recording.
+- The play button starts or resumes audio playback to the current output device.
+- The settings button launches the settings dialog.
+
+
+Hacking
+-------
+
+If you want to hack the application, here are some pointers to get started.
+
+The spectrum.pri file contains several macros which you can enable by uncommenting:
+- LOG_FOO      Enable logging from class Foo via qDebug()
+- DUMP_FOO     Dump data from class Foo to the file system
+               e.g. DUMP_SPECTRUMANALYSER writes files containing the raw FFT input and output.
+               Be aware that this can generate a *lot* of data and may slow the app down considerably.
+- DISABLE_FOO  Disable specified functionality
+
+If you don't like the combination of the waveform and progress bar in a single widget, separate them by commenting out SUPERIMPOSE_PROGRESS_ON_WAVEFORM.
+
+The spectrum.h file defines a number of parameters which can be played with.  These control things such as the number of audio samples analysed per FFT calculation, the range and number of bands displayed by the spectrograph, and so on.
+
+The part of the application which interacts with QtMultimedia is in the Engine class.
+
+Some ideas for enhancements to the app are listed in TODO.txt.  Feel free to start work on any of them :)
+
+
diff --git a/demos/spectrum/TODO.txt b/demos/spectrum/TODO.txt
new file mode 100644
index 0000000..dc3d8f3
--- /dev/null
+++ b/demos/spectrum/TODO.txt
@@ -0,0 +1,34 @@
+TODO list for spectrum analyser
+===============================
+
+Bug fixes
+---------
+
+
+New features
+------------
+
+* Wrap user-visible strings in tr()
+
+* Allow user to set frequency range
+There should be some constraints on this, e.g.
+	- Maximum frequency must not be greater than Nyquist frequency
+	- Range is divisible by number of bars?
+
+* Add more visualizers other than bar spectrogram
+e.g. Funky OpenGL visualizers, particle effects etc
+
+
+Non-functional stuff
+--------------------
+
+* Improve robustness of QComboBox -> enum mapping
+At the moment, SettingsDialog relies on casting the combobox item index directly to the enumerated type.  This is clearly a bit fragile...
+
+* For functions which take or return qint64 values, make a clear distinction between duration (microseconds) and length (bytes).
+A sensible convention would be that the default is bytes - i.e. microseconds must be indicated by adding a Us suffix, where not already obvious from the function name.
+
+
+
+
+
diff --git a/demos/spectrum/app/app.pro b/demos/spectrum/app/app.pro
new file mode 100644
index 0000000..9964d14
--- /dev/null
+++ b/demos/spectrum/app/app.pro
@@ -0,0 +1,119 @@
+include(../spectrum.pri)
+
+TEMPLATE = app
+
+TARGET = spectrum
+unix: !macx: !symbian: TARGET = spectrum.bin
+
+QT       += multimedia
+
+SOURCES  += main.cpp \
+            engine.cpp \
+            frequencyspectrum.cpp \
+            levelmeter.cpp \
+            mainwidget.cpp \
+            progressbar.cpp \
+            settingsdialog.cpp \
+            spectrograph.cpp \
+            spectrumanalyser.cpp \
+            tonegenerator.cpp \
+            tonegeneratordialog.cpp \
+            utils.cpp \
+            waveform.cpp \
+            wavfile.cpp
+
+HEADERS  += engine.h \
+            frequencyspectrum.h \
+            levelmeter.h \
+            mainwidget.h \
+            progressbar.h \
+            settingsdialog.h \
+            spectrograph.h \
+            spectrum.h \
+            spectrumanalyser.h \
+            tonegenerator.h \
+            tonegeneratordialog.h \
+            utils.h \
+            waveform.h \
+            wavfile.h
+
+INCLUDEPATH += ../fftreal
+
+RESOURCES = spectrum.qrc
+
+symbian {
+    # Platform security capability required to record audio on Symbian
+    TARGET.CAPABILITY += UserEnvironment
+
+    # Provide unique ID for the generated binary, required by Symbian OS
+    TARGET.UID3 = 0xA000E3FA
+}
+
+
+# Dynamic linkage against FFTReal DLL
+!contains(DEFINES, DISABLE_FFT) {
+    symbian {
+        # Must explicitly add the .dll suffix to ensure dynamic linkage
+        LIBS += -lfftreal.dll
+    } else {
+        macx {
+            # Link to fftreal framework
+            LIBS += -F../fftreal
+            LIBS += -framework fftreal
+        } else {
+            # Link to dynamic library which is written to ../bin
+            LIBS += -L../bin
+            LIBS += -lfftreal
+        }
+    }
+}
+
+
+# Deployment
+
+symbian {
+    include($$QT_SOURCE_TREE/demos/symbianpkgrules.pri)
+
+    !contains(DEFINES, DISABLE_FFT) {
+        # Include FFTReal DLL in the SIS file
+        fftreal.sources = $${EPOCROOT}epoc32/release/$(PLATFORM)/$(TARGET)/fftreal.dll
+        fftreal.path = !:/sys/bin
+        DEPLOYMENT += fftreal
+    }
+} else {
+    macx {
+        # Specify directory in which to create spectrum.app bundle
+        DESTDIR = ..
+
+        !contains(DEFINES, DISABLE_FFT) {
+            # Relocate fftreal.framework into spectrum.app bundle
+            framework_dir = ../spectrum.app/Contents/Frameworks
+            framework_name = fftreal.framework/Versions/1/fftreal
+            QMAKE_POST_LINK = \
+                mkdir -p $${framework_dir} &&\
+                rm -rf $${framework_dir}/fftreal.framework &&\
+                cp -R ../fftreal/fftreal.framework $${framework_dir} &&\
+                install_name_tool -id @executable_path/../Frameworks/$${framework_name} \
+                                  $${framework_dir}/$${framework_name} &&\
+                install_name_tool -change $${framework_name} \
+                                  @executable_path/../Frameworks/$${framework_name} \
+                                  ../spectrum.app/Contents/MacOS/spectrum
+        }
+    } else {
+        # Specify directory in which to create spectrum application
+        DESTDIR = ../bin
+
+        unix: !symbian {
+            # On unices other than Mac OSX, we copy a shell script into the bin directory.
+            # This script takes care of correctly setting the LD_LIBRARY_PATH so that
+            # the dynamic library can be located.
+            copy_launch_script.target = copy_launch_script
+            copy_launch_script.commands = \
+                install -m 0555 spectrum.sh ../bin/spectrum
+            QMAKE_EXTRA_TARGETS += copy_launch_script
+            POST_TARGETDEPS += copy_launch_script
+        }
+    }
+}
+
+
diff --git a/demos/spectrum/app/engine.cpp b/demos/spectrum/app/engine.cpp
new file mode 100644
index 0000000..5cdfb6d
--- /dev/null
+++ b/demos/spectrum/app/engine.cpp
@@ -0,0 +1,752 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "engine.h"
+#include "tonegenerator.h"
+#include "utils.h"
+
+#include <math.h>
+
+#include <QCoreApplication>
+#include <QMetaObject>
+#include <QSet>
+#include <QtMultimedia/QAudioInput>
+#include <QtMultimedia/QAudioOutput>
+#include <QDebug>
+#include <QThread>
+#include <QFile>
+
+//-----------------------------------------------------------------------------
+// Constants
+//-----------------------------------------------------------------------------
+
+const qint64 BufferDurationUs       = 10 * 1000000;
+const int    NotifyIntervalMs       = 100;
+
+// Size of the level calculation window in microseconds
+const int    LevelWindowUs          = 0.1 * 1000000;
+
+
+//-----------------------------------------------------------------------------
+// Helper functions
+//-----------------------------------------------------------------------------
+
+QDebug& operator<<(QDebug &debug, const QAudioFormat &format)
+{
+    debug << format.frequency() << "Hz"
+          << format.channels() << "channels";
+    return debug;
+}
+
+//-----------------------------------------------------------------------------
+// Constructor and destructor
+//-----------------------------------------------------------------------------
+
+Engine::Engine(QObject *parent)
+    :   QObject(parent)
+    ,   m_mode(QAudio::AudioInput)
+    ,   m_state(QAudio::StoppedState)
+    ,   m_generateTone(false)
+    ,   m_file(0)
+    ,   m_availableAudioInputDevices
+            (QAudioDeviceInfo::availableDevices(QAudio::AudioInput))
+    ,   m_audioInputDevice(QAudioDeviceInfo::defaultInputDevice())
+    ,   m_audioInput(0)
+    ,   m_audioInputIODevice(0)
+    ,   m_recordPosition(0)
+    ,   m_availableAudioOutputDevices
+            (QAudioDeviceInfo::availableDevices(QAudio::AudioOutput))
+    ,   m_audioOutputDevice(QAudioDeviceInfo::defaultOutputDevice())
+    ,   m_audioOutput(0)
+    ,   m_playPosition(0)
+    ,   m_dataLength(0)
+    ,   m_rmsLevel(0.0)
+    ,   m_peakLevel(0.0)
+    ,   m_spectrumLengthBytes(0)
+    ,   m_spectrumAnalyser()
+    ,   m_spectrumPosition(0)
+    ,   m_count(0)
+{
+    qRegisterMetaType<FrequencySpectrum>("FrequencySpectrum");
+    CHECKED_CONNECT(&m_spectrumAnalyser,
+                    SIGNAL(spectrumChanged(FrequencySpectrum)),
+                    this,
+                    SLOT(spectrumChanged(FrequencySpectrum)));
+
+    initialize();
+
+#ifdef DUMP_DATA
+    createOutputDir();
+#endif
+
+#ifdef DUMP_SPECTRUM
+    m_spectrumAnalyser.setOutputPath(outputPath());
+#endif
+}
+
+Engine::~Engine()
+{
+
+}
+
+//-----------------------------------------------------------------------------
+// Public functions
+//-----------------------------------------------------------------------------
+
+bool Engine::loadFile(const QString &fileName)
+{
+    bool result = false;
+    m_generateTone = false;
+
+    Q_ASSERT(!fileName.isEmpty());
+    Q_ASSERT(!m_file);
+    m_file = new QFile(fileName, this);
+    m_file->setFileName(fileName);
+    Q_ASSERT(m_file->exists());
+    if (m_file->open(QFile::ReadOnly)) {
+        m_wavFile.readHeader(*m_file);
+        if (isPCMS16LE(m_wavFile.format())) {
+            result = initialize();
+        } else {
+            emit errorMessage(tr("Audio format not supported"),
+                              formatToString(m_wavFile.format()));
+        }
+    } else {
+        emit errorMessage(tr("Could not open file"), fileName);
+    }
+
+    delete m_file;
+    m_file = 0;
+
+    return result;
+}
+
+bool Engine::generateTone(const Tone &tone)
+{
+    Q_ASSERT(!m_file);
+    m_generateTone = true;
+    m_tone = tone;
+    ENGINE_DEBUG << "Engine::generateTone"
+                 << "startFreq" << m_tone.startFreq
+                 << "endFreq" << m_tone.endFreq
+                 << "amp" << m_tone.amplitude;
+    return initialize();
+}
+
+bool Engine::generateSweptTone(qreal amplitude)
+{
+    Q_ASSERT(!m_file);
+    m_generateTone = true;
+    m_tone.startFreq = 1;
+    m_tone.endFreq = 0;
+    m_tone.amplitude = amplitude;
+    ENGINE_DEBUG << "Engine::generateSweptTone"
+                 << "startFreq" << m_tone.startFreq
+                 << "amp" << m_tone.amplitude;
+    return initialize();
+}
+
+bool Engine::initializeRecord()
+{
+    ENGINE_DEBUG << "Engine::initializeRecord";
+    Q_ASSERT(!m_file);
+    m_generateTone = false;
+    m_tone = SweptTone();
+    return initialize();
+}
+
+qint64 Engine::bufferDuration() const
+{
+    return BufferDurationUs;
+}
+
+qint64 Engine::dataDuration() const
+{
+    qint64 result = 0;
+    if (QAudioFormat() != m_format)
+        result = audioDuration(m_format, m_dataLength);
+    return result;
+}
+
+qint64 Engine::audioBufferLength() const
+{
+    qint64 length = 0;
+    if (QAudio::ActiveState == m_state || QAudio::IdleState == m_state) {
+        Q_ASSERT(QAudioFormat() != m_format);
+        switch (m_mode) {
+        case QAudio::AudioInput:
+            length = m_audioInput->bufferSize();
+            break;
+        case QAudio::AudioOutput:
+            length = m_audioOutput->bufferSize();
+            break;
+        }
+    }
+    return length;
+}
+
+void Engine::setWindowFunction(WindowFunction type)
+{
+    m_spectrumAnalyser.setWindowFunction(type);
+}
+
+
+//-----------------------------------------------------------------------------
+// Public slots
+//-----------------------------------------------------------------------------
+
+void Engine::startRecording()
+{
+    if (m_audioInput) {
+        if (QAudio::AudioInput == m_mode &&
+            QAudio::SuspendedState == m_state) {
+            m_audioInput->resume();
+        } else {
+            m_spectrumAnalyser.cancelCalculation();
+            spectrumChanged(0, 0, FrequencySpectrum());
+
+            m_buffer.fill(0);
+            setRecordPosition(0, true);
+            stopPlayback();
+            m_mode = QAudio::AudioInput;
+            CHECKED_CONNECT(m_audioInput, SIGNAL(stateChanged(QAudio::State)),
+                            this, SLOT(audioStateChanged(QAudio::State)));
+            CHECKED_CONNECT(m_audioInput, SIGNAL(notify()),
+                            this, SLOT(audioNotify()));
+            m_count = 0;
+            m_dataLength = 0;
+            emit dataDurationChanged(0);
+            m_audioInputIODevice = m_audioInput->start();
+            CHECKED_CONNECT(m_audioInputIODevice, SIGNAL(readyRead()),
+                            this, SLOT(audioDataReady()));
+        }
+    }
+}
+
+void Engine::startPlayback()
+{
+    if (m_audioOutput) {
+        if (QAudio::AudioOutput == m_mode &&
+            QAudio::SuspendedState == m_state) {
+#ifdef Q_OS_WIN
+            // The Windows backend seems to internally go back into ActiveState
+            // while still returning SuspendedState, so to ensure that it doesn't
+            // ignore the resume() call, we first re-suspend
+            m_audioOutput->suspend();
+#endif
+            m_audioOutput->resume();
+        } else {
+            m_spectrumAnalyser.cancelCalculation();
+            spectrumChanged(0, 0, FrequencySpectrum());
+
+            setPlayPosition(0, true);
+            stopRecording();
+            m_mode = QAudio::AudioOutput;
+            CHECKED_CONNECT(m_audioOutput, SIGNAL(stateChanged(QAudio::State)),
+                            this, SLOT(audioStateChanged(QAudio::State)));
+            CHECKED_CONNECT(m_audioOutput, SIGNAL(notify()),
+                            this, SLOT(audioNotify()));
+            m_count = 0;
+            m_audioOutputIODevice.close();
+            m_audioOutputIODevice.setBuffer(&m_buffer);
+            m_audioOutputIODevice.open(QIODevice::ReadOnly);
+            m_audioOutput->start(&m_audioOutputIODevice);
+        }
+    }
+}
+
+void Engine::suspend()
+{
+    if (QAudio::ActiveState == m_state ||
+        QAudio::IdleState == m_state) {
+        switch (m_mode) {
+        case QAudio::AudioInput:
+            m_audioInput->suspend();
+            break;
+        case QAudio::AudioOutput:
+            m_audioOutput->suspend();
+            break;
+        }
+    }
+}
+
+void Engine::setAudioInputDevice(const QAudioDeviceInfo &device)
+{
+    if (device.deviceName() != m_audioInputDevice.deviceName()) {
+        m_audioInputDevice = device;
+        initialize();
+    }
+}
+
+void Engine::setAudioOutputDevice(const QAudioDeviceInfo &device)
+{
+    if (device.deviceName() != m_audioOutputDevice.deviceName()) {
+        m_audioOutputDevice = device;
+        initialize();
+    }
+}
+
+
+//-----------------------------------------------------------------------------
+// Private slots
+//-----------------------------------------------------------------------------
+
+void Engine::audioNotify()
+{
+    switch (m_mode) {
+    case QAudio::AudioInput: {
+            const qint64 recordPosition =
+                    qMin(BufferDurationUs, m_audioInput->processedUSecs());
+            setRecordPosition(recordPosition);
+
+            // Calculate level of most recently captured data
+            qint64 levelLength = audioLength(m_format, LevelWindowUs);
+            levelLength = qMin(m_dataLength, levelLength);
+            const qint64 levelPosition = m_dataLength - levelLength;
+            calculateLevel(levelPosition, levelLength);
+
+            // Calculate spectrum of most recently captured data
+            if (m_dataLength >= m_spectrumLengthBytes) {
+                const qint64 spectrumPosition = m_dataLength - m_spectrumLengthBytes;
+                calculateSpectrum(spectrumPosition);
+            }
+        }
+        break;
+    case QAudio::AudioOutput: {
+            const qint64 playPosition =
+                    qMin(dataDuration(), m_audioOutput->processedUSecs());
+            setPlayPosition(playPosition);
+
+            qint64 analysisPosition = audioLength(m_format, playPosition);
+
+            // Calculate level of data starting at current playback position
+            const qint64 levelLength = audioLength(m_format, LevelWindowUs);
+            if (analysisPosition + levelLength < m_dataLength)
+                calculateLevel(analysisPosition, levelLength);
+
+            if (analysisPosition + m_spectrumLengthBytes < m_dataLength)
+                calculateSpectrum(analysisPosition);
+
+            if (dataDuration() == playPosition)
+                stopPlayback();
+        }
+        break;
+    }
+}
+
+void Engine::audioStateChanged(QAudio::State state)
+{
+    ENGINE_DEBUG << "Engine::audioStateChanged from" << m_state
+                 << "to" << state;
+
+    if (QAudio::StoppedState == state) {
+        // Check error
+        QAudio::Error error = QAudio::NoError;
+        switch (m_mode) {
+        case QAudio::AudioInput:
+            error = m_audioInput->error();
+            break;
+        case QAudio::AudioOutput:
+            error = m_audioOutput->error();
+            break;
+        }
+        if (QAudio::NoError != error) {
+            reset();
+            return;
+        }
+    }
+    setState(state);
+}
+
+void Engine::audioDataReady()
+{
+    const qint64 bytesReady = m_audioInput->bytesReady();
+    const qint64 bytesSpace = m_buffer.size() - m_dataLength;
+    const qint64 bytesToRead = qMin(bytesReady, bytesSpace);
+
+    const qint64 bytesRead = m_audioInputIODevice->read(
+                                       m_buffer.data() + m_dataLength,
+                                       bytesToRead);
+
+    if (bytesRead) {
+        m_dataLength += bytesRead;
+
+        const qint64 duration = audioDuration(m_format, m_dataLength);
+        emit dataDurationChanged(duration);
+    }
+
+    if (m_buffer.size() == m_dataLength)
+        stopRecording();
+}
+
+void Engine::spectrumChanged(const FrequencySpectrum &spectrum)
+{
+    ENGINE_DEBUG << "Engine::spectrumChanged" << "pos" << m_spectrumPosition;
+    const qint64 positionUs = audioDuration(m_format, m_spectrumPosition);
+    const qint64 lengthUs = audioDuration(m_format, m_spectrumLengthBytes);
+    emit spectrumChanged(positionUs, lengthUs, spectrum);
+}
+
+
+//-----------------------------------------------------------------------------
+// Private functions
+//-----------------------------------------------------------------------------
+
+void Engine::reset()
+{
+    stopRecording();
+    stopPlayback();
+    setState(QAudio::AudioInput, QAudio::StoppedState);
+    setFormat(QAudioFormat());
+    delete m_audioInput;
+    m_audioInput = 0;
+    m_audioInputIODevice = 0;
+    setRecordPosition(0);
+    delete m_audioOutput;
+    m_audioOutput = 0;
+    setPlayPosition(0);
+    m_buffer.clear();
+    m_dataLength = 0;
+    m_spectrumPosition = 0;
+    emit dataDurationChanged(0);
+    setLevel(0.0, 0.0, 0);
+}
+
+bool Engine::initialize()
+{
+    bool result = false;
+
+    reset();
+
+    if (selectFormat()) {
+        const qint64 bufferLength = audioLength(m_format, BufferDurationUs);
+        m_buffer.resize(bufferLength);
+        m_buffer.fill(0);
+        emit bufferDurationChanged(BufferDurationUs);
+
+        if (m_generateTone) {
+            if (0 == m_tone.endFreq) {
+                const qreal nyquist = nyquistFrequency(m_format);
+                m_tone.endFreq = qMin(qreal(SpectrumHighFreq), nyquist);
+            }
+
+            // Call function defined in utils.h, at global scope
+            ::generateTone(m_tone, m_format, m_buffer);
+            m_dataLength = m_buffer.size();
+            emit dataDurationChanged(bufferDuration());
+            setRecordPosition(bufferDuration());
+            result = true;
+        } else if (m_file) {
+            const qint64 length = m_wavFile.readData(*m_file, m_buffer, m_format);
+            if (length) {
+                m_dataLength = length;
+                emit dataDurationChanged(dataDuration());
+                setRecordPosition(dataDuration());
+                result = true;
+            }
+        } else {
+            m_audioInput = new QAudioInput(m_audioInputDevice, m_format, this);
+            m_audioInput->setNotifyInterval(NotifyIntervalMs);
+            result = true;
+        }
+
+        m_audioOutput = new QAudioOutput(m_audioOutputDevice, m_format, this);
+        m_audioOutput->setNotifyInterval(NotifyIntervalMs);
+        m_spectrumLengthBytes = SpectrumLengthSamples *
+                                (m_format.sampleSize() / 8) * m_format.channels();
+    } else {
+        if (m_file)
+            emit errorMessage(tr("Audio format not supported"),
+                              formatToString(m_format));
+        else if (m_generateTone)
+            emit errorMessage(tr("No suitable format found"), "");
+        else
+            emit errorMessage(tr("No common input / output format found"), "");
+    }
+
+    ENGINE_DEBUG << "Engine::initialize" << "format" << m_format;
+
+    return result;
+}
+
+bool Engine::selectFormat()
+{
+    bool foundSupportedFormat = false;
+
+    if (m_file) {
+        // Header is read from the WAV file; just need to check whether
+        // it is supported by the audio output device
+        QAudioFormat format = m_wavFile.format();
+        if (m_audioOutputDevice.isFormatSupported(m_wavFile.format())) {
+            setFormat(m_wavFile.format());
+            foundSupportedFormat = true;
+        } else {
+            // Try flipping mono <-> stereo
+            const int channels = (format.channels() == 1) ? 2 : 1;
+            format.setChannels(channels);
+            if (m_audioOutputDevice.isFormatSupported(format)) {
+                setFormat(format);
+                foundSupportedFormat = true;
+            }
+        }
+    } else {
+
+        QList<int> frequenciesList;
+    #ifdef Q_OS_WIN
+        // The Windows audio backend does not correctly report format support
+        // (see QTBUG-9100).  Furthermore, although the audio subsystem captures
+        // at 11025Hz, the resulting audio is corrupted.
+        frequenciesList += 8000;
+    #endif
+
+        if (!m_generateTone)
+            frequenciesList += m_audioInputDevice.supportedFrequencies();
+
+        frequenciesList += m_audioOutputDevice.supportedFrequencies();
+        frequenciesList = frequenciesList.toSet().toList(); // remove duplicates
+        qSort(frequenciesList);
+        ENGINE_DEBUG << "Engine::initialize frequenciesList" << frequenciesList;
+
+        QList<int> channelsList;
+        channelsList += m_audioInputDevice.supportedChannels();
+        channelsList += m_audioOutputDevice.supportedChannels();
+        channelsList = channelsList.toSet().toList();
+        qSort(channelsList);
+        ENGINE_DEBUG << "Engine::initialize channelsList" << channelsList;
+
+        QAudioFormat format;
+        format.setByteOrder(QAudioFormat::LittleEndian);
+        format.setCodec("audio/pcm");
+        format.setSampleSize(16);
+        format.setSampleType(QAudioFormat::SignedInt);
+        int frequency, channels;
+        foreach (frequency, frequenciesList) {
+            if (foundSupportedFormat)
+                break;
+            format.setFrequency(frequency);
+            foreach (channels, channelsList) {
+                format.setChannels(channels);
+                const bool inputSupport = m_generateTone ||
+                                          m_audioInputDevice.isFormatSupported(format);
+                const bool outputSupport = m_audioOutputDevice.isFormatSupported(format);
+                ENGINE_DEBUG << "Engine::initialize checking " << format
+                             << "input" << inputSupport
+                             << "output" << outputSupport;
+                if (inputSupport && outputSupport) {
+                    foundSupportedFormat = true;
+                    break;
+                }
+            }
+        }
+
+        if (!foundSupportedFormat)
+            format = QAudioFormat();
+
+        setFormat(format);
+    }
+
+    return foundSupportedFormat;
+}
+
+void Engine::stopRecording()
+{
+    if (m_audioInput) {
+        m_audioInput->stop();
+        QCoreApplication::instance()->processEvents();
+        m_audioInput->disconnect();
+    }
+    m_audioInputIODevice = 0;
+
+#ifdef DUMP_AUDIO
+    dumpData();
+#endif
+}
+
+void Engine::stopPlayback()
+{
+    if (m_audioOutput) {
+        m_audioOutput->stop();
+        QCoreApplication::instance()->processEvents();
+        m_audioOutput->disconnect();
+        setPlayPosition(0);
+    }
+}
+
+void Engine::setState(QAudio::State state)
+{
+    const bool changed = (m_state != state);
+    m_state = state;
+    if (changed)
+        emit stateChanged(m_mode, m_state);
+}
+
+void Engine::setState(QAudio::Mode mode, QAudio::State state)
+{
+    const bool changed = (m_mode != mode || m_state != state);
+    m_mode = mode;
+    m_state = state;
+    if (changed)
+        emit stateChanged(m_mode, m_state);
+}
+
+void Engine::setRecordPosition(qint64 position, bool forceEmit)
+{
+    const bool changed = (m_recordPosition != position);
+    m_recordPosition = position;
+    if (changed || forceEmit)
+        emit recordPositionChanged(m_recordPosition);
+}
+
+void Engine::setPlayPosition(qint64 position, bool forceEmit)
+{
+    const bool changed = (m_playPosition != position);
+    m_playPosition = position;
+    if (changed || forceEmit)
+        emit playPositionChanged(m_playPosition);
+}
+
+void Engine::calculateLevel(qint64 position, qint64 length)
+{
+#ifdef DISABLE_LEVEL
+    Q_UNUSED(position)
+    Q_UNUSED(length)
+#else
+    Q_ASSERT(position + length <= m_dataLength);
+
+    qreal peakLevel = 0.0;
+
+    qreal sum = 0.0;
+    const char *ptr = m_buffer.constData() + position;
+    const char *const end = ptr + length;
+    while (ptr < end) {
+        const qint16 value = *reinterpret_cast<const qint16*>(ptr);
+        const qreal fracValue = pcmToReal(value);
+        peakLevel = qMax(peakLevel, fracValue);
+        sum += fracValue * fracValue;
+        ptr += 2;
+    }
+    const int numSamples = length / 2;
+    qreal rmsLevel = sqrt(sum / numSamples);
+
+    rmsLevel = qMax(qreal(0.0), rmsLevel);
+    rmsLevel = qMin(qreal(1.0), rmsLevel);
+    setLevel(rmsLevel, peakLevel, numSamples);
+
+    ENGINE_DEBUG << "Engine::calculateLevel" << "pos" << position << "len" << length
+                 << "rms" << rmsLevel << "peak" << peakLevel;
+#endif
+}
+
+void Engine::calculateSpectrum(qint64 position)
+{
+#ifdef DISABLE_SPECTRUM
+    Q_UNUSED(position)
+#else
+    Q_ASSERT(position + m_spectrumLengthBytes <= m_dataLength);
+    Q_ASSERT(0 == m_spectrumLengthBytes % 2); // constraint of FFT algorithm
+
+    // QThread::currentThread is marked 'for internal use only', but
+    // we're only using it for debug output here, so it's probably OK :)
+    ENGINE_DEBUG << "Engine::calculateSpectrum" << QThread::currentThread()
+                 << "count" << m_count << "pos" << position << "len" << m_spectrumLengthBytes
+                 << "spectrumAnalyser.isReady" << m_spectrumAnalyser.isReady();
+
+    if(m_spectrumAnalyser.isReady()) {
+        m_spectrumBuffer = QByteArray::fromRawData(m_buffer.constData() + position,
+                                                   m_spectrumLengthBytes);
+        m_spectrumPosition = position;
+        m_spectrumAnalyser.calculate(m_spectrumBuffer, m_format);
+    }
+#endif
+}
+
+void Engine::setFormat(const QAudioFormat &format)
+{
+    const bool changed = (format != m_format);
+    m_format = format;
+    if (changed)
+        emit formatChanged(m_format);
+}
+
+void Engine::setLevel(qreal rmsLevel, qreal peakLevel, int numSamples)
+{
+    m_rmsLevel = rmsLevel;
+    m_peakLevel = peakLevel;
+    emit levelChanged(m_rmsLevel, m_peakLevel, numSamples);
+}
+
+#ifdef DUMP_DATA
+void Engine::createOutputDir()
+{
+    m_outputDir.setPath("output");
+
+    // Ensure output directory exists and is empty
+    if (m_outputDir.exists()) {
+        const QStringList files = m_outputDir.entryList(QDir::Files);
+        QString file;
+        foreach (file, files)
+            m_outputDir.remove(file);
+    } else {
+        QDir::current().mkdir("output");
+    }
+}
+#endif // DUMP_DATA
+
+#ifdef DUMP_AUDIO
+void Engine::dumpData()
+{
+    const QString txtFileName = m_outputDir.filePath("data.txt");
+    QFile txtFile(txtFileName);
+    txtFile.open(QFile::WriteOnly | QFile::Text);
+    QTextStream stream(&txtFile);
+    const qint16 *ptr = reinterpret_cast<const qint16*>(m_buffer.constData());
+    const int numSamples = m_dataLength / (2 * m_format.channels());
+    for (int i=0; i<numSamples; ++i) {
+        stream << i << "\t" << *ptr << "\n";
+        ptr += m_format.channels();
+    }
+
+    const QString pcmFileName = m_outputDir.filePath("data.pcm");
+    QFile pcmFile(pcmFileName);
+    pcmFile.open(QFile::WriteOnly);
+    pcmFile.write(m_buffer.constData(), m_dataLength);
+}
+#endif // DUMP_AUDIO
diff --git a/demos/spectrum/app/engine.h b/demos/spectrum/app/engine.h
new file mode 100644
index 0000000..7028247
--- /dev/null
+++ b/demos/spectrum/app/engine.h
@@ -0,0 +1,309 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+#ifndef ENGINE_H
+#define ENGINE_H
+
+#include "spectrum.h"
+#include "spectrumanalyser.h"
+#include "wavfile.h"
+
+#include <QObject>
+#include <QByteArray>
+#include <QBuffer>
+#include <QVector>
+#include <QtMultimedia/QAudioDeviceInfo>
+#include <QtMultimedia/QAudioFormat>
+
+#ifdef DUMP_CAPTURED_AUDIO
+#define DUMP_DATA
+#endif
+
+#ifdef DUMP_SPECTRUM
+#define DUMP_DATA
+#endif
+
+#ifdef DUMP_DATA
+#include <QDir>
+#endif
+
+class QAudioInput;
+class QAudioOutput;
+class FrequencySpectrum;
+class QFile;
+
+/**
+ * This class interfaces with the QtMultimedia audio classes, and also with
+ * the SpectrumAnalyser class.  Its role is to manage the capture and playback
+ * of audio data, meanwhile performing real-time analysis of the audio level
+ * and frequency spectrum.
+ */
+class Engine : public QObject {
+    Q_OBJECT
+public:
+    Engine(QObject *parent = 0);
+    ~Engine();
+
+    const QList<QAudioDeviceInfo>& availableAudioInputDevices() const
+                                    { return m_availableAudioInputDevices; }
+
+    const QList<QAudioDeviceInfo>& availableAudioOutputDevices() const
+                                    { return m_availableAudioOutputDevices; }
+
+    QAudio::Mode mode() const       { return m_mode; }
+    QAudio::State state() const     { return m_state; }
+
+    /**
+     * \return Reference to internal audio buffer
+     * \note This reference is valid for the lifetime of the Engine
+     */
+    const QByteArray& buffer() const    { return m_buffer; }
+
+    /**
+     * \return Current audio format
+     * \note May be QAudioFormat() if engine is not initialized
+     */
+    const QAudioFormat& format() const  { return m_format; }
+
+    /**
+     * Stop any ongoing recording or playback, and reset to ground state.
+     */
+    void reset();
+
+    /**
+     * Load data from WAV file
+     */
+    bool loadFile(const QString &fileName);
+
+    /**
+     * Generate tone
+     */
+    bool generateTone(const Tone &tone);
+
+    /**
+     * Generate tone
+     */
+    bool generateSweptTone(qreal amplitude);
+
+    /**
+     * Initialize for recording
+     */
+    bool initializeRecord();
+
+    /**
+     * Position of the audio input device.
+     * \return Position in microseconds.
+     */
+    qint64 recordPosition() const   { return m_recordPosition; }
+
+    /**
+     * RMS level of the most recently processed set of audio samples.
+     * \return Level in range (0.0, 1.0)
+     */
+    qreal rmsLevel() const          { return m_rmsLevel; }
+
+    /**
+     * Peak level of the most recently processed set of audio samples.
+     * \return Level in range (0.0, 1.0)
+     */
+    qreal peakLevel() const         { return m_peakLevel; }
+
+    /**
+     * Position of the audio output device.
+     * \return Position in microseconds.
+     */
+    qint64 playPosition() const     { return m_playPosition; }
+
+    /**
+     * Length of the internal engine buffer.
+     * \return Buffer length in microseconds.
+     */
+    qint64 bufferDuration() const;
+
+    /**
+     * Amount of data held in the buffer.
+     * \return Data duration in microseconds.
+     */
+    qint64 dataDuration() const;
+
+    /**
+     * Returns the size of the underlying audio buffer in bytes.
+     * This should be an approximation of the capture latency.
+     */
+    qint64 audioBufferLength() const;
+
+    /**
+     * Set window function applied to audio data before spectral analysis.
+     */
+    void setWindowFunction(WindowFunction type);
+
+public slots:
+    void startRecording();
+    void startPlayback();
+    void suspend();
+    void setAudioInputDevice(const QAudioDeviceInfo &device);
+    void setAudioOutputDevice(const QAudioDeviceInfo &device);
+
+signals:
+    void stateChanged(QAudio::Mode mode, QAudio::State state);
+
+    /**
+     * Informational message for non-modal display
+     */
+    void infoMessage(const QString &message, int durationMs);
+
+    /**
+     * Error message for modal display
+     */
+    void errorMessage(const QString &heading, const QString &detail);
+
+    /**
+     * Format of audio data has changed
+     */
+    void formatChanged(const QAudioFormat &format);
+
+    /**
+     * Length of buffer has changed.
+     * \param duration Duration in microseconds
+     */
+    void bufferDurationChanged(qint64 duration);
+
+    /**
+     * Amount of data in buffer has changed.
+     * \param duration Duration of data in microseconds
+     */
+    void dataDurationChanged(qint64 duration);
+
+    /**
+     * Position of the audio input device has changed.
+     * \param position Position in microseconds
+     */
+    void recordPositionChanged(qint64 position);
+
+    /**
+     * Position of the audio output device has changed.
+     * \param position Position in microseconds
+     */
+    void playPositionChanged(qint64 position);
+
+    /**
+     * Level changed
+     * \param rmsLevel RMS level in range 0.0 - 1.0
+     * \param peakLevel Peak level in range 0.0 - 1.0
+     * \param numSamples Number of audio samples analysed
+     */
+    void levelChanged(qreal rmsLevel, qreal peakLevel, int numSamples);
+
+    /**
+     * Spectrum has changed.
+     * \param position Position of start of window in microseconds
+     * \param length   Length of window in microseconds
+     * \param spectrum Resulting frequency spectrum
+     */
+    void spectrumChanged(qint64 position, qint64 length, const FrequencySpectrum &spectrum);
+
+private slots:
+    void audioNotify();
+    void audioStateChanged(QAudio::State state);
+    void audioDataReady();
+    void spectrumChanged(const FrequencySpectrum &spectrum);
+
+private:
+    bool initialize();
+    bool selectFormat();
+    void stopRecording();
+    void stopPlayback();
+    void setState(QAudio::State state);
+    void setState(QAudio::Mode mode, QAudio::State state);
+    void setFormat(const QAudioFormat &format);
+    void setRecordPosition(qint64 position, bool forceEmit = false);
+    void setPlayPosition(qint64 position, bool forceEmit = false);
+    void calculateLevel(qint64 position, qint64 length);
+    void calculateSpectrum(qint64 position);
+    void setLevel(qreal rmsLevel, qreal peakLevel, int numSamples);
+
+#ifdef DUMP_DATA
+    void createOutputDir();
+    QString outputPath() const { return m_outputDir.path(); }
+#endif
+
+#ifdef DUMP_CAPTURED_AUDIO
+    void dumpData();
+#endif
+
+private:
+    QAudio::Mode        m_mode;
+    QAudio::State       m_state;
+
+    bool                m_generateTone;
+    SweptTone           m_tone;
+
+    QFile*              m_file;
+    WavFile             m_wavFile;
+
+    QAudioFormat        m_format;
+
+    const QList<QAudioDeviceInfo> m_availableAudioInputDevices;
+    QAudioDeviceInfo    m_audioInputDevice;
+    QAudioInput*        m_audioInput;
+    QIODevice*          m_audioInputIODevice;
+    qint64              m_recordPosition;
+
+    const QList<QAudioDeviceInfo> m_availableAudioOutputDevices;
+    QAudioDeviceInfo    m_audioOutputDevice;
+    QAudioOutput*       m_audioOutput;
+    qint64              m_playPosition;
+    QBuffer             m_audioOutputIODevice;
+
+    QByteArray          m_buffer;
+    qint64              m_dataLength;
+
+    qreal               m_rmsLevel;
+    qreal               m_peakLevel;
+
+    int                 m_spectrumLengthBytes;
+    QByteArray          m_spectrumBuffer;
+    SpectrumAnalyser    m_spectrumAnalyser;
+    qint64              m_spectrumPosition;
+
+    int                 m_count;
+
+#ifdef DUMP_DATA
+    QDir                m_outputDir;
+#endif
+
+};
+
+#endif // ENGINE_H
diff --git a/demos/spectrum/app/frequencyspectrum.cpp b/demos/spectrum/app/frequencyspectrum.cpp
new file mode 100644
index 0000000..6ab80c2
--- /dev/null
+++ b/demos/spectrum/app/frequencyspectrum.cpp
@@ -0,0 +1,90 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "frequencyspectrum.h"
+
+FrequencySpectrum::FrequencySpectrum(int numPoints)
+    :   m_elements(numPoints)
+{
+
+}
+
+void FrequencySpectrum::reset()
+{
+    iterator i = begin();
+    for ( ; i != end(); ++i)
+        *i = Element();
+}
+
+int FrequencySpectrum::count() const
+{
+    return m_elements.count();
+}
+
+FrequencySpectrum::Element& FrequencySpectrum::operator[](int index)
+{
+    return m_elements[index];
+}
+
+const FrequencySpectrum::Element& FrequencySpectrum::operator[](int index) const
+{
+    return m_elements[index];
+}
+
+FrequencySpectrum::iterator FrequencySpectrum::begin()
+{
+    return m_elements.begin();
+}
+
+FrequencySpectrum::iterator FrequencySpectrum::end()
+{
+    return m_elements.end();
+}
+
+FrequencySpectrum::const_iterator FrequencySpectrum::begin() const
+{
+    return m_elements.begin();
+}
+
+FrequencySpectrum::const_iterator FrequencySpectrum::end() const
+{
+    return m_elements.end();
+}
diff --git a/demos/spectrum/app/frequencyspectrum.h b/demos/spectrum/app/frequencyspectrum.h
new file mode 100644
index 0000000..610ed6e
--- /dev/null
+++ b/demos/spectrum/app/frequencyspectrum.h
@@ -0,0 +1,93 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+#ifndef FREQUENCYSPECTRUM_H
+#define FREQUENCYSPECTRUM_H
+
+#include <QtCore/QVector>
+
+/**
+ * Represents a frequency spectrum as a series of elements, each of which
+ * consists of a frequency, an amplitude and a phase.
+ */
+class FrequencySpectrum {
+public:
+    FrequencySpectrum(int numPoints = 0);
+
+    struct Element {
+        Element()
+        :   frequency(0.0), amplitude(0.0), phase(0.0), clipped(false)
+        { }
+
+        /**
+         * Frequency in Hertz
+         */
+        qreal frequency;
+
+        /**
+         * Amplitude in range [0.0, 1.0]
+         */
+        qreal amplitude;
+
+        /**
+         * Phase in range [0.0, 2*PI]
+         */
+        qreal phase;
+
+        /**
+         * Indicates whether value has been clipped during spectrum analysis
+         */
+        bool clipped;
+    };
+
+    typedef QVector<Element>::iterator iterator;
+    typedef QVector<Element>::const_iterator const_iterator;
+
+    void reset();
+
+    int count() const;
+    Element& operator[](int index);
+    const Element& operator[](int index) const;
+    iterator begin();
+    iterator end();
+    const_iterator begin() const;
+    const_iterator end() const;
+
+private:
+    QVector<Element> m_elements;
+
+};
+
+#endif // FREQUENCYSPECTRUM_H
diff --git a/demos/spectrum/app/images/record.png b/demos/spectrum/app/images/record.png
new file mode 100644
index 0000000..e7493aa
--- /dev/null
+++ b/demos/spectrum/app/images/record.png
diff --git a/demos/spectrum/app/images/settings.png b/demos/spectrum/app/images/settings.png
new file mode 100644
index 0000000..12179dc
--- /dev/null
+++ b/demos/spectrum/app/images/settings.png
diff --git a/demos/spectrum/app/levelmeter.cpp b/demos/spectrum/app/levelmeter.cpp
new file mode 100644
index 0000000..eb37684
--- /dev/null
+++ b/demos/spectrum/app/levelmeter.cpp
@@ -0,0 +1,143 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "levelmeter.h"
+
+#include <math.h>
+
+#include <QPainter>
+#include <QTimer>
+#include <QDebug>
+
+
+// Constants
+const int RedrawInterval = 100; // ms
+const qreal PeakDecayRate = 0.001;
+const int PeakHoldLevelDuration = 2000; // ms
+
+
+LevelMeter::LevelMeter(QWidget *parent)
+    :   QWidget(parent)
+    ,   m_rmsLevel(0.0)
+    ,   m_peakLevel(0.0)
+    ,   m_decayedPeakLevel(0.0)
+    ,   m_peakDecayRate(PeakDecayRate)
+    ,   m_peakHoldLevel(0.0)
+    ,   m_redrawTimer(new QTimer(this))
+    ,   m_rmsColor(Qt::red)
+    ,   m_peakColor(255, 200, 200, 255)
+{
+    setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Preferred);
+    setMinimumWidth(30);
+
+    connect(m_redrawTimer, SIGNAL(timeout()), this, SLOT(redrawTimerExpired()));
+    m_redrawTimer->start(RedrawInterval);
+}
+
+LevelMeter::~LevelMeter()
+{
+
+}
+
+void LevelMeter::reset()
+{
+    m_rmsLevel = 0.0;
+    m_peakLevel = 0.0;
+    update();
+}
+
+void LevelMeter::levelChanged(qreal rmsLevel, qreal peakLevel, int numSamples)
+{
+    // Smooth the RMS signal
+    const qreal smooth = pow(0.9, static_cast<qreal>(numSamples) / 256); // TODO: remove this magic number
+    m_rmsLevel = (m_rmsLevel * smooth) + (rmsLevel * (1.0 - smooth));
+
+    if (peakLevel > m_decayedPeakLevel) {
+        m_peakLevel = peakLevel;
+        m_decayedPeakLevel = peakLevel;
+        m_peakLevelChanged.start();
+    }
+
+    if (peakLevel > m_peakHoldLevel) {
+        m_peakHoldLevel = peakLevel;
+        m_peakHoldLevelChanged.start();
+    }
+
+    update();
+}
+
+void LevelMeter::redrawTimerExpired()
+{
+    // Decay the peak signal
+    const int elapsedMs = m_peakLevelChanged.elapsed();
+    const qreal decayAmount = m_peakDecayRate * elapsedMs;
+    if (decayAmount < m_peakLevel)
+        m_decayedPeakLevel = m_peakLevel - decayAmount;
+    else
+        m_decayedPeakLevel = 0.0;
+
+    // Check whether to clear the peak hold level
+    if (m_peakHoldLevelChanged.elapsed() > PeakHoldLevelDuration)
+        m_peakHoldLevel = 0.0;
+
+    update();
+}
+
+void LevelMeter::paintEvent(QPaintEvent *event)
+{
+    Q_UNUSED(event)
+
+    QPainter painter(this);
+    painter.fillRect(rect(), Qt::black);
+
+    QRect bar = rect();
+
+    bar.setTop(rect().top() + (1.0 - m_peakHoldLevel) * rect().height());
+    bar.setBottom(bar.top() + 5);
+    painter.fillRect(bar, m_rmsColor);
+    bar.setBottom(rect().bottom());
+
+    bar.setTop(rect().top() + (1.0 - m_decayedPeakLevel) * rect().height());
+    painter.fillRect(bar, m_peakColor);
+
+    bar.setTop(rect().top() + (1.0 - m_rmsLevel) * rect().height());
+    painter.fillRect(bar, m_rmsColor);
+}
diff --git a/demos/spectrum/app/levelmeter.h b/demos/spectrum/app/levelmeter.h
new file mode 100644
index 0000000..7d4238d
--- /dev/null
+++ b/demos/spectrum/app/levelmeter.h
@@ -0,0 +1,111 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+#ifndef LEVELMETER_H
+#define LEVELMETER_H
+
+#include <QTime>
+#include <QWidget>
+
+/**
+ * Widget which displays a vertical audio level meter, indicating the
+ * RMS and peak levels of the window of audio samples most recently analysed
+ * by the Engine.
+ */
+class LevelMeter : public QWidget {
+    Q_OBJECT
+public:
+    LevelMeter(QWidget *parent = 0);
+    ~LevelMeter();
+
+    void paintEvent(QPaintEvent *event);
+
+public slots:
+    void reset();
+    void levelChanged(qreal rmsLevel, qreal peakLevel, int numSamples);
+
+private slots:
+    void redrawTimerExpired();
+
+private:
+    /**
+     * Height of RMS level bar.
+     * Range 0.0 - 1.0.
+     */
+    qreal m_rmsLevel;
+
+    /**
+     * Most recent peak level.
+     * Range 0.0 - 1.0.
+     */
+    qreal m_peakLevel;
+
+    /**
+     * Height of peak level bar.
+     * This is calculated by decaying m_peakLevel depending on the
+     * elapsed time since m_peakLevelChanged, and the value of m_decayRate.
+     */
+    qreal m_decayedPeakLevel;
+
+    /**
+     * Time at which m_peakLevel was last changed.
+     */
+    QTime m_peakLevelChanged;
+
+    /**
+     * Rate at which peak level bar decays.
+     * Expressed in level units / millisecond.
+     */
+    qreal m_peakDecayRate;
+
+    /**
+     * High watermark of peak level.
+     * Range 0.0 - 1.0.
+     */
+    qreal m_peakHoldLevel;
+
+    /**
+     * Time at which m_peakHoldLevel was last changed.
+     */
+    QTime m_peakHoldLevelChanged;
+
+    QTimer *m_redrawTimer;
+
+    QColor m_rmsColor;
+    QColor m_peakColor;
+
+};
+
+#endif // LEVELMETER_H
diff --git a/demos/spectrum/app/main.cpp b/demos/spectrum/app/main.cpp
new file mode 100644
index 0000000..6e2b6fc
--- /dev/null
+++ b/demos/spectrum/app/main.cpp
@@ -0,0 +1,58 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtGui/QApplication>
+#include "mainwidget.h"
+
+int main(int argc, char **argv)
+{
+    QApplication app(argc, argv);
+    app.setApplicationName("QtMultimedia spectrum analyser");
+    MainWidget w;
+
+#ifdef Q_OS_SYMBIAN
+    w.showMaximized();
+#else
+    w.show();
+#endif
+
+    return app.exec();
+}
diff --git a/demos/spectrum/app/mainwidget.cpp b/demos/spectrum/app/mainwidget.cpp
new file mode 100644
index 0000000..3b7c306
--- /dev/null
+++ b/demos/spectrum/app/mainwidget.cpp
@@ -0,0 +1,455 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "engine.h"
+#include "levelmeter.h"
+#include "mainwidget.h"
+#include "waveform.h"
+#include "progressbar.h"
+#include "settingsdialog.h"
+#include "spectrograph.h"
+#include "tonegeneratordialog.h"
+#include "utils.h"
+
+#include <QLabel>
+#include <QPushButton>
+#include <QHBoxLayout>
+#include <QVBoxLayout>
+#include <QStyle>
+#include <QMenu>
+#include <QFileDialog>
+#include <QTimerEvent>
+#include <QMessageBox>
+
+const int NullTimerId = -1;
+
+MainWidget::MainWidget(QWidget *parent)
+    :   QWidget(parent)
+    ,   m_mode(NoMode)
+    ,   m_engine(new Engine(this))
+#ifndef DISABLE_WAVEFORM
+    ,   m_waveform(new Waveform(m_engine->buffer(), this))
+#endif
+    ,   m_progressBar(new ProgressBar(this))
+    ,   m_spectrograph(new Spectrograph(this))
+    ,   m_levelMeter(new LevelMeter(this))
+    ,   m_modeButton(new QPushButton(this))
+    ,   m_recordButton(new QPushButton(this))
+    ,   m_pauseButton(new QPushButton(this))
+    ,   m_playButton(new QPushButton(this))
+    ,   m_settingsButton(new QPushButton(this))
+    ,   m_infoMessage(new QLabel(tr("Select a mode to begin"), this))
+    ,   m_infoMessageTimerId(NullTimerId)
+    ,   m_settingsDialog(new SettingsDialog(
+            m_engine->availableAudioInputDevices(),
+            m_engine->availableAudioOutputDevices(),
+            this))
+    ,   m_toneGeneratorDialog(new ToneGeneratorDialog(this))
+    ,   m_modeMenu(new QMenu(this))
+    ,   m_loadFileAction(0)
+    ,   m_generateToneAction(0)
+    ,   m_recordAction(0)
+{
+    m_spectrograph->setParams(SpectrumNumBands, SpectrumLowFreq, SpectrumHighFreq);
+
+    createUi();
+    connectUi();
+}
+
+MainWidget::~MainWidget()
+{
+
+}
+
+
+//-----------------------------------------------------------------------------
+// Public slots
+//-----------------------------------------------------------------------------
+
+void MainWidget::stateChanged(QAudio::Mode mode, QAudio::State state)
+{
+    Q_UNUSED(mode);
+
+    updateButtonStates();
+
+    if (QAudio::ActiveState != state && QAudio::SuspendedState != state) {
+        m_levelMeter->reset();
+        m_spectrograph->reset();
+    }
+}
+
+void MainWidget::formatChanged(const QAudioFormat &format)
+{
+   infoMessage(formatToString(format), NullMessageTimeout);
+
+#ifndef DISABLE_WAVEFORM
+    if (QAudioFormat() != format) {
+        m_waveform->initialize(format, WaveformTileLength,
+                               WaveformWindowDuration);
+    }
+#endif
+}
+
+void MainWidget::spectrumChanged(qint64 position, qint64 length,
+                                 const FrequencySpectrum &spectrum)
+{
+    m_progressBar->windowChanged(position, length);
+    m_spectrograph->spectrumChanged(spectrum);
+}
+
+void MainWidget::infoMessage(const QString &message, int timeoutMs)
+{
+    m_infoMessage->setText(message);
+
+    if (NullTimerId != m_infoMessageTimerId) {
+        killTimer(m_infoMessageTimerId);
+        m_infoMessageTimerId = NullTimerId;
+    }
+
+    if (NullMessageTimeout != timeoutMs)
+        m_infoMessageTimerId = startTimer(timeoutMs);
+}
+
+void MainWidget::errorMessage(const QString &heading, const QString &detail)
+{
+#ifdef Q_OS_SYMBIAN
+    const QString message = heading + "\n" + detail;
+    QMessageBox::warning(this, "", message, QMessageBox::Close);
+#else
+    QMessageBox::warning(this, heading, detail, QMessageBox::Close);
+#endif
+}
+
+void MainWidget::timerEvent(QTimerEvent *event)
+{
+    Q_ASSERT(event->timerId() == m_infoMessageTimerId);
+    Q_UNUSED(event) // suppress warnings in release builds
+    killTimer(m_infoMessageTimerId);
+    m_infoMessageTimerId = NullTimerId;
+    m_infoMessage->setText("");
+}
+
+void MainWidget::positionChanged(qint64 positionUs)
+{
+#ifndef DISABLE_WAVEFORM
+    qint64 positionBytes = audioLength(m_engine->format(), positionUs);
+    m_waveform->positionChanged(positionBytes);
+#else
+    Q_UNUSED(positionUs)
+#endif
+}
+
+void MainWidget::bufferDurationChanged(qint64 durationUs)
+{
+    m_progressBar->bufferDurationChanged(durationUs);
+}
+
+
+//-----------------------------------------------------------------------------
+// Private slots
+//-----------------------------------------------------------------------------
+
+void MainWidget::dataDurationChanged(qint64 duration)
+{
+#ifndef DISABLE_WAVEFORM
+    const qint64 dataLength = audioLength(m_engine->format(), duration);
+    m_waveform->dataLengthChanged(dataLength);
+#else
+    Q_UNUSED(duration)
+#endif
+
+    updateButtonStates();
+}
+
+void MainWidget::showFileDialog()
+{
+    reset();
+    const QString dir;
+    const QStringList fileNames = QFileDialog::getOpenFileNames(this, tr("Open WAV file"), dir, "*.wav");
+    if (fileNames.count()) {
+        setMode(LoadFileMode);
+        m_engine->loadFile(fileNames.front());
+        updateButtonStates();
+    }
+}
+
+void MainWidget::showSettingsDialog()
+{
+    reset();
+    m_settingsDialog->exec();
+    if (m_settingsDialog->result() == QDialog::Accepted) {
+        m_engine->setAudioInputDevice(m_settingsDialog->inputDevice());
+        m_engine->setAudioOutputDevice(m_settingsDialog->outputDevice());
+        m_engine->setWindowFunction(m_settingsDialog->windowFunction());
+    }
+}
+
+void MainWidget::showToneGeneratorDialog()
+{
+    reset();
+    m_toneGeneratorDialog->exec();
+    if (m_toneGeneratorDialog->result() == QDialog::Accepted) {
+        setMode(GenerateToneMode);
+        const qreal amplitude = m_toneGeneratorDialog->amplitude();
+        if (m_toneGeneratorDialog->isFrequencySweepEnabled()) {
+            m_engine->generateSweptTone(amplitude);
+        } else {
+            const qreal frequency = m_toneGeneratorDialog->frequency();
+            const Tone tone(frequency, amplitude);
+            m_engine->generateTone(tone);
+            updateButtonStates();
+        }
+    }
+}
+
+void MainWidget::initializeRecord()
+{
+    reset();
+    setMode(RecordMode);
+    if (m_engine->initializeRecord())
+        updateButtonStates();
+}
+
+
+//-----------------------------------------------------------------------------
+// Private functions
+//-----------------------------------------------------------------------------
+
+void MainWidget::createUi()
+{
+    createMenus();
+
+    setWindowTitle(tr("Spectrum Analyser"));
+
+    QVBoxLayout *windowLayout = new QVBoxLayout(this);
+
+    m_infoMessage->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
+    m_infoMessage->setAlignment(Qt::AlignHCenter);
+    windowLayout->addWidget(m_infoMessage);
+
+#ifdef SUPERIMPOSE_PROGRESS_ON_WAVEFORM
+    QScopedPointer<QHBoxLayout> waveformLayout(new QHBoxLayout);
+    waveformLayout->addWidget(m_progressBar);
+    m_progressBar->setMinimumHeight(m_waveform->minimumHeight());
+    waveformLayout->setMargin(0);
+    m_waveform->setLayout(waveformLayout.data());
+    waveformLayout.take();
+    windowLayout->addWidget(m_waveform);
+#else
+#ifndef DISABLE_WAVEFORM
+    windowLayout->addWidget(m_waveform);
+#endif // DISABLE_WAVEFORM
+    windowLayout->addWidget(m_progressBar);
+#endif // SUPERIMPOSE_PROGRESS_ON_WAVEFORM
+
+    // Spectrograph and level meter
+
+    QScopedPointer<QHBoxLayout> analysisLayout(new QHBoxLayout);
+    analysisLayout->addWidget(m_spectrograph);
+    analysisLayout->addWidget(m_levelMeter);
+    windowLayout->addLayout(analysisLayout.data());
+    analysisLayout.take();
+
+    // Button panel
+
+    const QSize buttonSize(30, 30);
+
+    m_modeButton->setText(tr("Mode"));
+
+    m_recordIcon = QIcon(":/images/record.png");
+    m_recordButton->setIcon(m_recordIcon);
+    m_recordButton->setEnabled(false);
+    m_recordButton->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
+    m_recordButton->setMinimumSize(buttonSize);
+
+    m_pauseIcon = style()->standardIcon(QStyle::SP_MediaPause);
+    m_pauseButton->setIcon(m_pauseIcon);
+    m_pauseButton->setEnabled(false);
+    m_pauseButton->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
+    m_pauseButton->setMinimumSize(buttonSize);
+
+    m_playIcon = style()->standardIcon(QStyle::SP_MediaPlay);
+    m_playButton->setIcon(m_playIcon);
+    m_playButton->setEnabled(false);
+    m_playButton->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
+    m_playButton->setMinimumSize(buttonSize);
+
+    m_settingsIcon = QIcon(":/images/settings.png");
+    m_settingsButton->setIcon(m_settingsIcon);
+    m_settingsButton->setEnabled(true);
+    m_settingsButton->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
+    m_settingsButton->setMinimumSize(buttonSize);
+
+    QScopedPointer<QHBoxLayout> buttonPanelLayout(new QHBoxLayout);
+    buttonPanelLayout->addStretch();
+    buttonPanelLayout->addWidget(m_modeButton);
+    buttonPanelLayout->addWidget(m_recordButton);
+    buttonPanelLayout->addWidget(m_pauseButton);
+    buttonPanelLayout->addWidget(m_playButton);
+    buttonPanelLayout->addWidget(m_settingsButton);
+
+    QWidget *buttonPanel = new QWidget(this);
+    buttonPanel->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
+    buttonPanel->setLayout(buttonPanelLayout.data());
+    buttonPanelLayout.take(); // ownership transferred to buttonPanel
+
+    QScopedPointer<QHBoxLayout> bottomPaneLayout(new QHBoxLayout);
+    bottomPaneLayout->addWidget(buttonPanel);
+    windowLayout->addLayout(bottomPaneLayout.data());
+    bottomPaneLayout.take(); // ownership transferred to windowLayout
+
+    // Apply layout
+
+    setLayout(windowLayout);
+}
+
+void MainWidget::connectUi()
+{
+    CHECKED_CONNECT(m_recordButton, SIGNAL(clicked()),
+            m_engine, SLOT(startRecording()));
+
+    CHECKED_CONNECT(m_pauseButton, SIGNAL(clicked()),
+            m_engine, SLOT(suspend()));
+
+    CHECKED_CONNECT(m_playButton, SIGNAL(clicked()),
+            m_engine, SLOT(startPlayback()));
+
+    CHECKED_CONNECT(m_settingsButton, SIGNAL(clicked()),
+            this, SLOT(showSettingsDialog()));
+
+    CHECKED_CONNECT(m_engine, SIGNAL(stateChanged(QAudio::Mode,QAudio::State)),
+            this, SLOT(stateChanged(QAudio::Mode,QAudio::State)));
+
+    CHECKED_CONNECT(m_engine, SIGNAL(formatChanged(const QAudioFormat &)),
+            this, SLOT(formatChanged(const QAudioFormat &)));
+
+    m_progressBar->bufferDurationChanged(m_engine->bufferDuration());
+
+    CHECKED_CONNECT(m_engine, SIGNAL(bufferDurationChanged(qint64)),
+            this, SLOT(bufferDurationChanged(qint64)));
+
+    CHECKED_CONNECT(m_engine, SIGNAL(dataDurationChanged(qint64)),
+            this, SLOT(dataDurationChanged(qint64)));
+
+    CHECKED_CONNECT(m_engine, SIGNAL(recordPositionChanged(qint64)),
+            m_progressBar, SLOT(recordPositionChanged(qint64)));
+
+    CHECKED_CONNECT(m_engine, SIGNAL(playPositionChanged(qint64)),
+            m_progressBar, SLOT(playPositionChanged(qint64)));
+
+    CHECKED_CONNECT(m_engine, SIGNAL(recordPositionChanged(qint64)),
+            this, SLOT(positionChanged(qint64)));
+
+    CHECKED_CONNECT(m_engine, SIGNAL(playPositionChanged(qint64)),
+            this, SLOT(positionChanged(qint64)));
+
+    CHECKED_CONNECT(m_engine, SIGNAL(levelChanged(qreal, qreal, int)),
+            m_levelMeter, SLOT(levelChanged(qreal, qreal, int)));
+
+    CHECKED_CONNECT(m_engine, SIGNAL(spectrumChanged(qint64, qint64, const FrequencySpectrum &)),
+            this, SLOT(spectrumChanged(qint64, qint64, const FrequencySpectrum &)));
+
+    CHECKED_CONNECT(m_engine, SIGNAL(infoMessage(QString, int)),
+            this, SLOT(infoMessage(QString, int)));
+
+    CHECKED_CONNECT(m_engine, SIGNAL(errorMessage(QString, QString)),
+            this, SLOT(errorMessage(QString, QString)));
+
+    CHECKED_CONNECT(m_spectrograph, SIGNAL(infoMessage(QString, int)),
+            this, SLOT(infoMessage(QString, int)));
+}
+
+void MainWidget::createMenus()
+{
+    m_modeButton->setMenu(m_modeMenu);
+
+    m_generateToneAction = m_modeMenu->addAction(tr("Play generated tone"));
+    m_recordAction = m_modeMenu->addAction(tr("Record and play back"));
+    m_loadFileAction = m_modeMenu->addAction(tr("Play file"));
+
+    m_loadFileAction->setCheckable(true);
+    m_generateToneAction->setCheckable(true);
+    m_recordAction->setCheckable(true);
+
+    connect(m_loadFileAction, SIGNAL(triggered(bool)), this, SLOT(showFileDialog()));
+    connect(m_generateToneAction, SIGNAL(triggered(bool)), this, SLOT(showToneGeneratorDialog()));
+    connect(m_recordAction, SIGNAL(triggered(bool)), this, SLOT(initializeRecord()));
+}
+
+void MainWidget::updateButtonStates()
+{
+    const bool recordEnabled = ((QAudio::AudioOutput == m_engine->mode() ||
+                                (QAudio::ActiveState != m_engine->state() &&
+                                 QAudio::IdleState != m_engine->state())) &&
+                                RecordMode == m_mode);
+    m_recordButton->setEnabled(recordEnabled);
+
+    const bool pauseEnabled = (QAudio::ActiveState == m_engine->state() ||
+                               QAudio::IdleState == m_engine->state());
+    m_pauseButton->setEnabled(pauseEnabled);
+
+    const bool playEnabled = (m_engine->dataDuration() &&
+                              (QAudio::AudioOutput != m_engine->mode() ||
+                               (QAudio::ActiveState != m_engine->state() &&
+                                QAudio::IdleState != m_engine->state())));
+    m_playButton->setEnabled(playEnabled);
+}
+
+void MainWidget::reset()
+{
+#ifndef DISABLE_WAVEFORM
+    m_waveform->reset();
+#endif
+    m_engine->reset();
+    m_levelMeter->reset();
+    m_spectrograph->reset();
+    m_progressBar->reset();
+}
+
+void MainWidget::setMode(Mode mode)
+{
+
+    m_mode = mode;
+    m_loadFileAction->setChecked(LoadFileMode == mode);
+    m_generateToneAction->setChecked(GenerateToneMode == mode);
+    m_recordAction->setChecked(RecordMode == mode);
+}
+
diff --git a/demos/spectrum/app/mainwidget.h b/demos/spectrum/app/mainwidget.h
new file mode 100644
index 0000000..8e24f4a
--- /dev/null
+++ b/demos/spectrum/app/mainwidget.h
@@ -0,0 +1,136 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+#ifndef MAINWIDGET_H
+#define MAINWIDGET_H
+
+#include <QWidget>
+#include <QIcon>
+#include <QtMultimedia/qaudio.h>
+
+class Engine;
+class FrequencySpectrum;
+class ProgressBar;
+class Spectrograph;
+class Waveform;
+class LevelMeter;
+class SettingsDialog;
+class ToneGeneratorDialog;
+class QAudioFormat;
+class QLabel;
+class QPushButton;
+class QMenu;
+class QAction;
+
+/**
+ * Main application widget, responsible for connecting the various UI
+ * elements to the Engine.
+ */
+class MainWidget : public QWidget {
+    Q_OBJECT
+public:
+    MainWidget(QWidget *parent = 0);
+    ~MainWidget();
+
+    // QObject
+    void timerEvent(QTimerEvent *event);
+
+public slots:
+    void stateChanged(QAudio::Mode mode, QAudio::State state);
+    void formatChanged(const QAudioFormat &format);
+    void spectrumChanged(qint64 position, qint64 length,
+                         const FrequencySpectrum &spectrum);
+    void infoMessage(const QString &message, int timeoutMs);
+    void errorMessage(const QString &heading, const QString &detail);
+    void positionChanged(qint64 position);
+    void bufferDurationChanged(qint64 duration);
+
+private slots:
+    void showFileDialog();
+    void showSettingsDialog();
+    void showToneGeneratorDialog();
+    void initializeRecord();
+    void dataDurationChanged(qint64 duration);
+
+private:
+    void createUi();
+    void createMenus();
+    void connectUi();
+    void updateButtonStates();
+    void reset();
+
+    enum Mode {
+        NoMode,
+        RecordMode,
+        GenerateToneMode,
+        LoadFileMode
+    };
+
+    void setMode(Mode mode);
+
+private:
+    Mode                    m_mode;
+
+    Engine*                 m_engine;
+
+    Waveform*               m_waveform;
+    ProgressBar*            m_progressBar;
+    Spectrograph*           m_spectrograph;
+    LevelMeter*             m_levelMeter;
+
+    QPushButton*            m_modeButton;
+    QPushButton*            m_recordButton;
+    QIcon                   m_recordIcon;
+    QPushButton*            m_pauseButton;
+    QIcon                   m_pauseIcon;
+    QPushButton*            m_playButton;
+    QIcon                   m_playIcon;
+    QPushButton*            m_settingsButton;
+    QIcon                   m_settingsIcon;
+
+    QLabel*                 m_infoMessage;
+    int                     m_infoMessageTimerId;
+
+    SettingsDialog*         m_settingsDialog;
+    ToneGeneratorDialog*    m_toneGeneratorDialog;
+
+    QMenu*                  m_modeMenu;
+    QAction*                m_loadFileAction;
+    QAction*                m_generateToneAction;
+    QAction*                m_recordAction;
+
+};
+
+#endif // MAINWIDGET_H
diff --git a/demos/spectrum/app/progressbar.cpp b/demos/spectrum/app/progressbar.cpp
new file mode 100644
index 0000000..256acf0
--- /dev/null
+++ b/demos/spectrum/app/progressbar.cpp
@@ -0,0 +1,141 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "progressbar.h"
+#include "spectrum.h"
+#include <QPainter>
+
+ProgressBar::ProgressBar(QWidget *parent)
+    :   QWidget(parent)
+    ,   m_bufferDuration(0)
+    ,   m_recordPosition(0)
+    ,   m_playPosition(0)
+    ,   m_windowPosition(0)
+    ,   m_windowLength(0)
+{
+    setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
+    setMinimumHeight(30);
+#ifdef SUPERIMPOSE_PROGRESS_ON_WAVEFORM
+    setAutoFillBackground(false);
+#endif
+}
+
+ProgressBar::~ProgressBar()
+{
+
+}
+
+void ProgressBar::reset()
+{
+    m_bufferDuration = 0;
+    m_recordPosition = 0;
+    m_playPosition = 0;
+    m_windowPosition = 0;
+    m_windowLength = 0;
+    update();
+}
+
+void ProgressBar::paintEvent(QPaintEvent * /*event*/)
+{
+    QPainter painter(this);
+
+    QColor bufferColor(0, 0, 255);
+    QColor windowColor(0, 255, 0);
+
+#ifdef SUPERIMPOSE_PROGRESS_ON_WAVEFORM
+    bufferColor.setAlphaF(0.5);
+    windowColor.setAlphaF(0.5);
+#else
+    painter.fillRect(rect(), Qt::black);
+#endif
+
+    if (m_bufferDuration) {
+        QRect bar = rect();
+        const qreal play = qreal(m_playPosition) / m_bufferDuration;
+        bar.setLeft(rect().left() + play * rect().width());
+        const qreal record = qreal(m_recordPosition) / m_bufferDuration;
+        bar.setRight(rect().left() + record * rect().width());
+        painter.fillRect(bar, bufferColor);
+
+        QRect window = rect();
+        const qreal windowLeft = qreal(m_windowPosition) / m_bufferDuration;
+        window.setLeft(rect().left() + windowLeft * rect().width());
+        const qreal windowWidth = qreal(m_windowLength) / m_bufferDuration;
+        window.setWidth(windowWidth * rect().width());
+        painter.fillRect(window, windowColor);
+    }
+}
+
+void ProgressBar::bufferDurationChanged(qint64 bufferSize)
+{
+    m_bufferDuration = bufferSize;
+    m_recordPosition = 0;
+    m_playPosition = 0;
+    m_windowPosition = 0;
+    m_windowLength = 0;
+    repaint();
+}
+
+void ProgressBar::recordPositionChanged(qint64 recordPosition)
+{
+    Q_ASSERT(recordPosition >= 0);
+    Q_ASSERT(recordPosition <= m_bufferDuration);
+    m_recordPosition = recordPosition;
+    repaint();
+}
+
+void ProgressBar::playPositionChanged(qint64 playPosition)
+{
+    Q_ASSERT(playPosition >= 0);
+    Q_ASSERT(playPosition <= m_bufferDuration);
+    m_playPosition = playPosition;
+    repaint();
+}
+
+void ProgressBar::windowChanged(qint64 position, qint64 length)
+{
+    Q_ASSERT(position >= 0);
+    Q_ASSERT(position <= m_bufferDuration);
+    Q_ASSERT(position + length <= m_bufferDuration);
+    m_windowPosition = position;
+    m_windowLength = length;
+    repaint();
+}
diff --git a/demos/spectrum/app/progressbar.h b/demos/spectrum/app/progressbar.h
new file mode 100644
index 0000000..8dc4765
--- /dev/null
+++ b/demos/spectrum/app/progressbar.h
@@ -0,0 +1,69 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+#ifndef PROGRESSBAR_H
+#define PROGRESSBAR_H
+
+#include <QWidget>
+
+/**
+ * Widget which displays a the current fill state of the Engine's internal
+ * buffer, and the current play/record position within that buffer.
+ */
+class ProgressBar : public QWidget {
+    Q_OBJECT
+public:
+    ProgressBar(QWidget *parent = 0);
+    ~ProgressBar();
+
+    void reset();
+    void paintEvent(QPaintEvent *event);
+
+public slots:
+    void bufferDurationChanged(qint64 bufferSize);
+    void recordPositionChanged(qint64 recordPosition);
+    void playPositionChanged(qint64 playPosition);
+    void windowChanged(qint64 position, qint64 length);
+
+private:
+    qint64 m_bufferDuration;
+    qint64 m_recordPosition;
+    qint64 m_playPosition;
+    qint64 m_windowPosition;
+    qint64 m_windowLength;
+
+};
+
+#endif // PROGRESSBAR_H
diff --git a/demos/spectrum/app/settingsdialog.cpp b/demos/spectrum/app/settingsdialog.cpp
new file mode 100644
index 0000000..204b43f
--- /dev/null
+++ b/demos/spectrum/app/settingsdialog.cpp
@@ -0,0 +1,149 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "settingsdialog.h"
+#include <QComboBox>
+#include <QDialogButtonBox>
+#include <QLabel>
+#include <QPushButton>
+#include <QVBoxLayout>
+#include <QCheckBox>
+#include <QSlider>
+#include <QSpinBox>
+
+SettingsDialog::SettingsDialog(
+            const QList<QAudioDeviceInfo> &availableInputDevices,
+            const QList<QAudioDeviceInfo> &availableOutputDevices,
+            QWidget *parent)
+    :   QDialog(parent)
+    ,   m_windowFunction(DefaultWindowFunction)
+    ,   m_inputDeviceComboBox(new QComboBox(this))
+    ,   m_outputDeviceComboBox(new QComboBox(this))
+    ,   m_windowFunctionComboBox(new QComboBox(this))
+{
+    QVBoxLayout *dialogLayout = new QVBoxLayout(this);
+
+    // Populate combo boxes
+
+    QAudioDeviceInfo device;
+    foreach (device, availableInputDevices)
+        m_inputDeviceComboBox->addItem(device.deviceName(),
+                                       qVariantFromValue(device));
+    foreach (device, availableOutputDevices)
+        m_outputDeviceComboBox->addItem(device.deviceName(),
+                                       qVariantFromValue(device));
+
+    m_windowFunctionComboBox->addItem(tr("None"), qVariantFromValue(int(NoWindow)));
+    m_windowFunctionComboBox->addItem("Hann", qVariantFromValue(int(HannWindow)));
+    m_windowFunctionComboBox->setCurrentIndex(m_windowFunction);
+
+    // Initialize default devices
+    if (!availableInputDevices.empty())
+        m_inputDevice = availableInputDevices.front();
+    if (!availableOutputDevices.empty())
+        m_outputDevice = availableOutputDevices.front();
+
+    // Add widgets to layout
+
+    QScopedPointer<QHBoxLayout> inputDeviceLayout(new QHBoxLayout);
+    QLabel *inputDeviceLabel = new QLabel(tr("Input device"), this);
+    inputDeviceLayout->addWidget(inputDeviceLabel);
+    inputDeviceLayout->addWidget(m_inputDeviceComboBox);
+    dialogLayout->addLayout(inputDeviceLayout.data());
+    inputDeviceLayout.take(); // ownership transferred to dialogLayout
+
+    QScopedPointer<QHBoxLayout> outputDeviceLayout(new QHBoxLayout);
+    QLabel *outputDeviceLabel = new QLabel(tr("Output device"), this);
+    outputDeviceLayout->addWidget(outputDeviceLabel);
+    outputDeviceLayout->addWidget(m_outputDeviceComboBox);
+    dialogLayout->addLayout(outputDeviceLayout.data());
+    outputDeviceLayout.take(); // ownership transferred to dialogLayout
+
+    QScopedPointer<QHBoxLayout> windowFunctionLayout(new QHBoxLayout);
+    QLabel *windowFunctionLabel = new QLabel(tr("Window function"), this);
+    windowFunctionLayout->addWidget(windowFunctionLabel);
+    windowFunctionLayout->addWidget(m_windowFunctionComboBox);
+    dialogLayout->addLayout(windowFunctionLayout.data());
+    windowFunctionLayout.take(); // ownership transferred to dialogLayout
+
+    // Connect
+    CHECKED_CONNECT(m_inputDeviceComboBox, SIGNAL(activated(int)),
+                    this, SLOT(inputDeviceChanged(int)));
+    CHECKED_CONNECT(m_outputDeviceComboBox, SIGNAL(activated(int)),
+                    this, SLOT(outputDeviceChanged(int)));
+    CHECKED_CONNECT(m_windowFunctionComboBox, SIGNAL(activated(int)),
+                    this, SLOT(windowFunctionChanged(int)));
+
+    // Add standard buttons to layout
+    QDialogButtonBox *buttonBox = new QDialogButtonBox(this);
+    buttonBox->setStandardButtons(QDialogButtonBox::Ok | QDialogButtonBox::Cancel);
+    dialogLayout->addWidget(buttonBox);
+
+    // Connect standard buttons
+    CHECKED_CONNECT(buttonBox->button(QDialogButtonBox::Ok), SIGNAL(clicked()),
+                    this, SLOT(accept()));
+    CHECKED_CONNECT(buttonBox->button(QDialogButtonBox::Cancel), SIGNAL(clicked()),
+                    this, SLOT(reject()));
+
+    setLayout(dialogLayout);
+}
+
+SettingsDialog::~SettingsDialog()
+{
+
+}
+
+void SettingsDialog::windowFunctionChanged(int index)
+{
+    m_windowFunction = static_cast<WindowFunction>(
+            m_windowFunctionComboBox->itemData(index).value<int>());
+}
+
+void SettingsDialog::inputDeviceChanged(int index)
+{
+    m_inputDevice = m_inputDeviceComboBox->itemData(index).value<QAudioDeviceInfo>();
+}
+
+void SettingsDialog::outputDeviceChanged(int index)
+{
+    m_outputDevice = m_outputDeviceComboBox->itemData(index).value<QAudioDeviceInfo>();
+}
+
diff --git a/demos/spectrum/app/settingsdialog.h b/demos/spectrum/app/settingsdialog.h
new file mode 100644
index 0000000..5f613c0
--- /dev/null
+++ b/demos/spectrum/app/settingsdialog.h
@@ -0,0 +1,82 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+#ifndef SETTINGSDIALOG_H
+#define SETTINGSDIALOG_H
+
+#include "spectrum.h"
+#include <QDialog>
+#include <QtMultimedia/QAudioDeviceInfo>
+
+class QComboBox;
+class QCheckBox;
+class QSlider;
+class QSpinBox;
+class QGridLayout;
+
+/**
+ * Dialog used to control settings such as the audio input / output device
+ * and the windowing function.
+ */
+class SettingsDialog : public QDialog {
+    Q_OBJECT
+public:
+    SettingsDialog(const QList<QAudioDeviceInfo> &availableInputDevices,
+                   const QList<QAudioDeviceInfo> &availableOutputDevices,
+                   QWidget *parent = 0);
+    ~SettingsDialog();
+
+    WindowFunction windowFunction() const           { return m_windowFunction; }
+    const QAudioDeviceInfo& inputDevice() const     { return m_inputDevice; }
+    const QAudioDeviceInfo& outputDevice() const    { return m_outputDevice; }
+
+private slots:
+    void windowFunctionChanged(int index);
+    void inputDeviceChanged(int index);
+    void outputDeviceChanged(int index);
+
+private:
+    WindowFunction   m_windowFunction;
+    QAudioDeviceInfo m_inputDevice;
+    QAudioDeviceInfo m_outputDevice;
+
+    QComboBox*      m_inputDeviceComboBox;
+    QComboBox*      m_outputDeviceComboBox;
+
+    QComboBox*      m_windowFunctionComboBox;
+
+};
+
+#endif // SETTINGSDIALOG_H
diff --git a/demos/spectrum/app/spectrograph.cpp b/demos/spectrum/app/spectrograph.cpp
new file mode 100644
index 0000000..1fcf434
--- /dev/null
+++ b/demos/spectrum/app/spectrograph.cpp
@@ -0,0 +1,242 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "spectrograph.h"
+#include <QPainter>
+#include <QMouseEvent>
+#include <QDebug>
+#include <QTimerEvent>
+
+const int NullTimerId = -1;
+const int NullIndex = -1;
+const int BarSelectionInterval = 2000;
+
+Spectrograph::Spectrograph(QWidget *parent)
+    :   QWidget(parent)
+    ,   m_barSelected(NullIndex)
+    ,   m_timerId(NullTimerId)
+    ,   m_lowFreq(0.0)
+    ,   m_highFreq(0.0)
+{
+    setMinimumHeight(100);
+}
+
+Spectrograph::~Spectrograph()
+{
+
+}
+
+void Spectrograph::setParams(int numBars, qreal lowFreq, qreal highFreq)
+{
+    Q_ASSERT(numBars > 0);
+    Q_ASSERT(highFreq > lowFreq);
+    m_bars.resize(numBars);
+    m_lowFreq = lowFreq;
+    m_highFreq = highFreq;
+    updateBars();
+}
+
+void Spectrograph::timerEvent(QTimerEvent *event)
+{
+    Q_ASSERT(event->timerId() == m_timerId);
+    Q_UNUSED(event) // suppress warnings in release builds
+    killTimer(m_timerId);
+    m_timerId = NullTimerId;
+    m_barSelected = NullIndex;
+    update();
+}
+
+void Spectrograph::paintEvent(QPaintEvent *event)
+{
+    Q_UNUSED(event)
+
+    QPainter painter(this);
+    painter.fillRect(rect(), Qt::black);
+
+    const int numBars = m_bars.count();
+
+    // Highlight region of selected bar
+    if (m_barSelected != NullIndex && numBars) {
+        QRect regionRect = rect();
+        regionRect.setLeft(m_barSelected * rect().width() / numBars);
+        regionRect.setWidth(rect().width() / numBars);
+        QColor regionColor(202, 202, 64);
+        painter.setBrush(Qt::DiagCrossPattern);
+        painter.fillRect(regionRect, regionColor);
+        painter.setBrush(Qt::NoBrush);
+    }
+
+    QColor barColor(51, 204, 102);
+    QColor clipColor(255, 255, 0);
+
+    // Draw the outline
+    const QColor gridColor = barColor.darker();
+    QPen gridPen(gridColor);
+    painter.setPen(gridPen);
+    painter.drawLine(rect().topLeft(), rect().topRight());
+    painter.drawLine(rect().topRight(), rect().bottomRight());
+    painter.drawLine(rect().bottomRight(), rect().bottomLeft());
+    painter.drawLine(rect().bottomLeft(), rect().topLeft());
+
+    QVector<qreal> dashes;
+    dashes << 2 << 2;
+    gridPen.setDashPattern(dashes);
+    painter.setPen(gridPen);
+
+    // Draw vertical lines between bars
+    if (numBars) {
+        const int numHorizontalSections = numBars;
+        QLine line(rect().topLeft(), rect().bottomLeft());
+        for (int i=1; i<numHorizontalSections; ++i) {
+            line.translate(rect().width()/numHorizontalSections, 0);
+            painter.drawLine(line);
+        }
+    }
+
+    // Draw horizontal lines
+    const int numVerticalSections = 10;
+    QLine line(rect().topLeft(), rect().topRight());
+    for (int i=1; i<numVerticalSections; ++i) {
+        line.translate(0, rect().height()/numVerticalSections);
+        painter.drawLine(line);
+    }
+
+    barColor = barColor.lighter();
+    barColor.setAlphaF(0.75);
+    clipColor.setAlphaF(0.75);
+
+    // Draw the bars
+    if (numBars) {
+        // Calculate width of bars and gaps
+        const int widgetWidth = rect().width();
+        const int barPlusGapWidth = widgetWidth / numBars;
+        const int barWidth = 0.8 * barPlusGapWidth;
+        const int gapWidth = barPlusGapWidth - barWidth;
+        const int paddingWidth = widgetWidth - numBars * (barWidth + gapWidth);
+        const int leftPaddingWidth = (paddingWidth + gapWidth) / 2;
+        const int barHeight = rect().height() - 2 * gapWidth;
+
+        for (int i=0; i<numBars; ++i) {
+            const qreal value = m_bars[i].value;
+            Q_ASSERT(value >= 0.0 && value <= 1.0);
+            QRect bar = rect();
+            bar.setLeft(rect().left() + leftPaddingWidth + (i * (gapWidth + barWidth)));
+            bar.setWidth(barWidth);
+            bar.setTop(rect().top() + gapWidth + (1.0 - value) * barHeight);
+            bar.setBottom(rect().bottom() - gapWidth);
+
+            QColor color = barColor;
+            if (m_bars[i].clipped)
+                color = clipColor;
+
+            painter.fillRect(bar, color);
+        }
+    }
+}
+
+void Spectrograph::mousePressEvent(QMouseEvent *event)
+{
+    const QPoint pos = event->pos();
+    const int index = m_bars.count() * (pos.x() - rect().left()) / rect().width();
+    selectBar(index);
+}
+
+void Spectrograph::reset()
+{
+    m_spectrum.reset();
+    spectrumChanged(m_spectrum);
+}
+
+void Spectrograph::spectrumChanged(const FrequencySpectrum &spectrum)
+{
+    m_spectrum = spectrum;
+    updateBars();
+}
+
+int Spectrograph::barIndex(qreal frequency) const
+{
+    Q_ASSERT(frequency >= m_lowFreq && frequency < m_highFreq);
+    const qreal bandWidth = (m_highFreq - m_lowFreq) / m_bars.count();
+    const int index = (frequency - m_lowFreq) / bandWidth;
+    if(index <0 || index >= m_bars.count())
+        Q_ASSERT(false);
+    return index;
+}
+
+QPair<qreal, qreal> Spectrograph::barRange(int index) const
+{
+    Q_ASSERT(index >= 0 && index < m_bars.count());
+    const qreal bandWidth = (m_highFreq - m_lowFreq) / m_bars.count();
+    return QPair<qreal, qreal>(index * bandWidth, (index+1) * bandWidth);
+}
+
+void Spectrograph::updateBars()
+{
+    m_bars.fill(Bar());
+    FrequencySpectrum::const_iterator i = m_spectrum.begin();
+    const FrequencySpectrum::const_iterator end = m_spectrum.end();
+    for ( ; i != end; ++i) {
+        const FrequencySpectrum::Element e = *i;
+        if (e.frequency >= m_lowFreq && e.frequency < m_highFreq) {
+            Bar &bar = m_bars[barIndex(e.frequency)];
+            bar.value = qMax(bar.value, e.amplitude);
+            bar.clipped |= e.clipped;
+        }
+    }
+    update();
+}
+
+void Spectrograph::selectBar(int index) {
+    const QPair<qreal, qreal> frequencyRange = barRange(index);
+    const QString message = QString("%1 - %2 Hz")
+                                .arg(frequencyRange.first)
+                                .arg(frequencyRange.second);
+    emit infoMessage(message, BarSelectionInterval);
+
+    if (NullTimerId != m_timerId)
+        killTimer(m_timerId);
+    m_timerId = startTimer(BarSelectionInterval);
+
+    m_barSelected = index;
+    update();
+}
+
+
diff --git a/demos/spectrum/app/spectrograph.h b/demos/spectrum/app/spectrograph.h
new file mode 100644
index 0000000..837a1a5
--- /dev/null
+++ b/demos/spectrum/app/spectrograph.h
@@ -0,0 +1,94 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+#ifndef SPECTROGRAPH_H
+#define SPECTROGRAPH_H
+
+#include <QWidget>
+#include "frequencyspectrum.h"
+
+class QMouseEvent;
+
+/**
+ * Widget which displays a spectrograph showing the frequency spectrum
+ * of the window of audio samples most recently analysed by the Engine.
+ */
+class Spectrograph : public QWidget {
+    Q_OBJECT
+public:
+    Spectrograph(QWidget *parent = 0);
+    ~Spectrograph();
+
+    void setParams(int numBars, qreal lowFreq, qreal highFreq);
+
+    // QObject
+    void timerEvent(QTimerEvent *event);
+
+    // QWidget
+    void paintEvent(QPaintEvent *event);
+    void mousePressEvent(QMouseEvent *event);
+
+signals:
+    void infoMessage(const QString &message, int intervalMs);
+
+public slots:
+    void reset();
+    void spectrumChanged(const FrequencySpectrum &spectrum);
+
+private:
+    int barIndex(qreal frequency) const;
+    QPair<qreal, qreal> barRange(int barIndex) const;
+    void updateBars();
+
+    void selectBar(int index);
+
+private:
+    struct Bar {
+        Bar() : value(0.0), clipped(false) { }
+        qreal   value;
+        bool    clipped;
+    };
+
+    QVector<Bar>        m_bars;
+    int                 m_barSelected;
+    int                 m_timerId;
+    qreal               m_lowFreq;
+    qreal               m_highFreq;
+    FrequencySpectrum   m_spectrum;
+
+
+};
+
+#endif // SPECTROGRAPH_H
diff --git a/demos/spectrum/app/spectrum.h b/demos/spectrum/app/spectrum.h
new file mode 100644
index 0000000..47b88ae
--- /dev/null
+++ b/demos/spectrum/app/spectrum.h
@@ -0,0 +1,139 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+#ifndef SPECTRUM_H
+#define SPECTRUM_H
+
+#include <QtCore/qglobal.h>
+#include "utils.h"
+#include "fftreal_wrapper.h" // For FFTLengthPowerOfTwo
+
+//-----------------------------------------------------------------------------
+// Constants
+//-----------------------------------------------------------------------------
+
+// Number of audio samples used to calculate the frequency spectrum
+const int    SpectrumLengthSamples  = PowerOfTwo<FFTLengthPowerOfTwo>::Result;
+
+// Number of bands in the frequency spectrum
+const int    SpectrumNumBands       = 10;
+
+// Lower bound of first band in the spectrum
+const qreal  SpectrumLowFreq        = 0.0; // Hz
+
+// Upper band of last band in the spectrum
+const qreal  SpectrumHighFreq       = 1000.0; // Hz
+
+// Waveform window size in microseconds
+const qint64 WaveformWindowDuration = 500 * 1000;
+
+// Length of waveform tiles in bytes
+// Ideally, these would match the QAudio*::bufferSize(), but that isn't
+// available until some time after QAudio*::start() has been called, and we
+// need this value in order to initialize the waveform display.
+// We therefore just choose a sensible value.
+const int   WaveformTileLength      = 4096;
+
+// Fudge factor used to calculate the spectrum bar heights
+const qreal SpectrumAnalyserMultiplier = 0.15;
+
+// Disable message timeout
+const int   NullMessageTimeout      = -1;
+
+
+//-----------------------------------------------------------------------------
+// Types and data structures
+//-----------------------------------------------------------------------------
+
+enum WindowFunction {
+    NoWindow,
+    HannWindow
+};
+
+const WindowFunction DefaultWindowFunction = HannWindow;
+
+struct Tone {
+    Tone(qreal freq = 0.0, qreal amp = 0.0)
+    :   frequency(freq), amplitude(amp)
+    { }
+
+    // Start and end frequencies for swept tone generation
+    qreal   frequency;
+
+    // Amplitude in range [0.0, 1.0]
+    qreal   amplitude;
+};
+
+struct SweptTone {
+    SweptTone(qreal start = 0.0, qreal end = 0.0, qreal amp = 0.0)
+    :   startFreq(start), endFreq(end), amplitude(amp)
+    { Q_ASSERT(end >= start); }
+
+    SweptTone(const Tone &tone)
+    :   startFreq(tone.frequency), endFreq(tone.frequency), amplitude(tone.amplitude)
+    { }
+
+    // Start and end frequencies for swept tone generation
+    qreal   startFreq;
+    qreal   endFreq;
+
+    // Amplitude in range [0.0, 1.0]
+    qreal   amplitude;
+};
+
+
+//-----------------------------------------------------------------------------
+// Macros
+//-----------------------------------------------------------------------------
+
+// Macro which connects a signal to a slot, and which causes application to
+// abort if the connection fails.  This is intended to catch programming errors
+// such as mis-typing a signal or slot name.  It is necessary to write our own
+// macro to do this - the following idiom
+//     Q_ASSERT(connect(source, signal, receiver, slot));
+// will not work because Q_ASSERT compiles to a no-op in release builds.
+
+#define CHECKED_CONNECT(source, signal, receiver, slot) \
+    if(!connect(source, signal, receiver, slot)) \
+        qt_assert_x(Q_FUNC_INFO, "CHECKED_CONNECT failed", __FILE__, __LINE__);
+
+// Handle some dependencies between macros defined in the .pro file
+
+#ifdef DISABLE_WAVEFORM
+#undef SUPERIMPOSE_PROGRESS_ON_WAVEFORM
+#endif
+
+#endif // SPECTRUM_H
+
diff --git a/demos/spectrum/app/spectrum.qrc b/demos/spectrum/app/spectrum.qrc
new file mode 100644
index 0000000..6100479
--- /dev/null
+++ b/demos/spectrum/app/spectrum.qrc
@@ -0,0 +1,7 @@
+<!DOCTYPE RCC><RCC version="1.0">
+<qresource>
+    <file>images/record.png</file>
+    <file>images/settings.png</file>
+</qresource>
+</RCC>
+
diff --git a/demos/spectrum/app/spectrum.sh b/demos/spectrum/app/spectrum.sh
new file mode 100644
index 0000000..75ad6c2
--- /dev/null
+++ b/demos/spectrum/app/spectrum.sh
@@ -0,0 +1,9 @@
+#!/bin/sh
+
+# Shell script for launching spectrum application on Unix systems other than Mac OSX
+
+bindir=`dirname "$0"`
+LD_LIBRARY_PATH="${bindir}:${LD_LIBRARY_PATH}"
+export LD_LIBRARY_PATH
+exec "${bindir}/spectrum.bin" ${1+"$@"}
+
diff --git a/demos/spectrum/app/spectrumanalyser.cpp b/demos/spectrum/app/spectrumanalyser.cpp
new file mode 100644
index 0000000..54d3f5e
--- /dev/null
+++ b/demos/spectrum/app/spectrumanalyser.cpp
@@ -0,0 +1,280 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "spectrumanalyser.h"
+#include "utils.h"
+
+#include <QtCore/qmath.h>
+#include <QtCore/qmetatype.h>
+#include <QtMultimedia/QAudioFormat>
+#include <QThread>
+
+#include "fftreal_wrapper.h"
+
+SpectrumAnalyserThread::SpectrumAnalyserThread(QObject *parent)
+    :   QObject(parent)
+#ifndef DISABLE_FFT
+    ,   m_fft(new FFTRealWrapper)
+#endif
+    ,   m_numSamples(SpectrumLengthSamples)
+    ,   m_windowFunction(DefaultWindowFunction)
+    ,   m_window(SpectrumLengthSamples, 0.0)
+    ,   m_input(SpectrumLengthSamples, 0.0)
+    ,   m_output(SpectrumLengthSamples, 0.0)
+    ,   m_spectrum(SpectrumLengthSamples)
+#ifdef SPECTRUM_ANALYSER_SEPARATE_THREAD
+    ,   m_thread(new QThread(this))
+#endif
+{
+#ifdef SPECTRUM_ANALYSER_SEPARATE_THREAD
+    moveToThread(m_thread);
+    m_thread->start();
+#endif
+    calculateWindow();
+}
+
+SpectrumAnalyserThread::~SpectrumAnalyserThread()
+{
+#ifndef DISABLE_FFT
+    delete m_fft;
+#endif
+}
+
+void SpectrumAnalyserThread::setWindowFunction(WindowFunction type)
+{
+    m_windowFunction = type;
+    calculateWindow();
+}
+
+void SpectrumAnalyserThread::calculateWindow()
+{
+    for (int i=0; i<m_numSamples; ++i) {
+        DataType x = 0.0;
+
+        switch (m_windowFunction) {
+        case NoWindow:
+            x = 1.0;
+            break;
+        case HannWindow:
+            x = 0.5 * (1 - qCos((2 * M_PI * i) / (m_numSamples - 1)));
+            break;
+        default:
+            Q_ASSERT(false);
+        }
+
+        m_window[i] = x;
+    }
+}
+
+void SpectrumAnalyserThread::calculateSpectrum(const QByteArray &buffer,
+                                                int inputFrequency,
+                                                int bytesPerSample)
+{
+#ifndef DISABLE_FFT
+    Q_ASSERT(buffer.size() == m_numSamples * bytesPerSample);
+
+    // Initialize data array
+    const char *ptr = buffer.constData();
+    for (int i=0; i<m_numSamples; ++i) {
+        const qint16 pcmSample = *reinterpret_cast<const qint16*>(ptr);
+        // Scale down to range [-1.0, 1.0]
+        const DataType realSample = pcmToReal(pcmSample);
+        const DataType windowedSample = realSample * m_window[i];
+        m_input[i] = windowedSample;
+        ptr += bytesPerSample;
+    }
+
+    // Calculate the FFT
+    m_fft->calculateFFT(m_output.data(), m_input.data());
+
+    // Analyse output to obtain amplitude and phase for each frequency
+    for (int i=2; i<=m_numSamples/2; ++i) {
+        // Calculate frequency of this complex sample
+        m_spectrum[i].frequency = qreal(i * inputFrequency) / (m_numSamples);
+
+        const qreal real = m_output[i];
+        qreal imag = 0.0;
+        if (i>0 && i<m_numSamples/2)
+            imag = m_output[m_numSamples/2 + i];
+
+        const qreal magnitude = sqrt(real*real + imag*imag);
+        qreal amplitude = SpectrumAnalyserMultiplier * log(magnitude);
+
+        // Bound amplitude to [0.0, 1.0]
+        m_spectrum[i].clipped = (amplitude > 1.0);
+        amplitude = qMax(qreal(0.0), amplitude);
+        amplitude = qMin(qreal(1.0), amplitude);
+        m_spectrum[i].amplitude = amplitude;
+    }
+#endif
+
+    emit calculationComplete(m_spectrum);
+}
+
+
+//=============================================================================
+// SpectrumAnalyser
+//=============================================================================
+
+SpectrumAnalyser::SpectrumAnalyser(QObject *parent)
+    :   QObject(parent)
+    ,   m_thread(new SpectrumAnalyserThread(this))
+    ,   m_state(Idle)
+#ifdef DUMP_SPECTRUMANALYSER
+    ,   m_count(0)
+#endif
+{
+    CHECKED_CONNECT(m_thread, SIGNAL(calculationComplete(FrequencySpectrum)),
+                    this, SLOT(calculationComplete(FrequencySpectrum)));
+}
+
+SpectrumAnalyser::~SpectrumAnalyser()
+{
+
+}
+
+#ifdef DUMP_SPECTRUMANALYSER
+void SpectrumAnalyser::setOutputPath(const QString &outputDir)
+{
+    m_outputDir.setPath(outputDir);
+    m_textFile.setFileName(m_outputDir.filePath("spectrum.txt"));
+    m_textFile.open(QIODevice::WriteOnly | QIODevice::Text);
+    m_textStream.setDevice(&m_textFile);
+}
+#endif
+
+//-----------------------------------------------------------------------------
+// Public functions
+//-----------------------------------------------------------------------------
+
+void SpectrumAnalyser::setWindowFunction(WindowFunction type)
+{
+    const bool b = QMetaObject::invokeMethod(m_thread, "setWindowFunction",
+                              Qt::AutoConnection,
+                              Q_ARG(WindowFunction, type));
+    Q_ASSERT(b);
+    Q_UNUSED(b) // suppress warnings in release builds
+}
+
+void SpectrumAnalyser::calculate(const QByteArray &buffer,
+                         const QAudioFormat &format)
+{
+    // QThread::currentThread is marked 'for internal use only', but
+    // we're only using it for debug output here, so it's probably OK :)
+    SPECTRUMANALYSER_DEBUG << "SpectrumAnalyser::calculate"
+                           << QThread::currentThread()
+                           << "state" << m_state;
+
+    if (isReady()) {
+        Q_ASSERT(isPCMS16LE(format));
+
+        const int bytesPerSample = format.sampleSize() * format.channels() / 8;
+
+#ifdef DUMP_SPECTRUMANALYSER
+        m_count++;
+        const QString pcmFileName = m_outputDir.filePath(QString("spectrum_%1.pcm").arg(m_count, 4, 10, QChar('0')));
+        QFile pcmFile(pcmFileName);
+        pcmFile.open(QIODevice::WriteOnly);
+        const int bufferLength = m_numSamples * bytesPerSample;
+        pcmFile.write(buffer, bufferLength);
+
+        m_textStream << "TimeDomain " << m_count << "\n";
+        const qint16* input = reinterpret_cast<const qint16*>(buffer);
+        for (int i=0; i<m_numSamples; ++i) {
+            m_textStream << i << "\t" << *input << "\n";
+            input += format.channels();
+        }
+#endif
+
+        m_state = Busy;
+
+        // Invoke SpectrumAnalyserThread::calculateSpectrum using QMetaObject.  If
+        // m_thread is in a different thread from the current thread, the
+        // calculation will be done in the child thread.
+        // Once the calculation is finished, a calculationChanged signal will be
+        // emitted by m_thread.
+        const bool b = QMetaObject::invokeMethod(m_thread, "calculateSpectrum",
+                                  Qt::AutoConnection,
+                                  Q_ARG(QByteArray, buffer),
+                                  Q_ARG(int, format.frequency()),
+                                  Q_ARG(int, bytesPerSample));
+        Q_ASSERT(b);
+        Q_UNUSED(b) // suppress warnings in release builds
+
+#ifdef DUMP_SPECTRUMANALYSER
+        m_textStream << "FrequencySpectrum " << m_count << "\n";
+        FrequencySpectrum::const_iterator x = m_spectrum.begin();
+        for (int i=0; i<m_numSamples; ++i, ++x)
+            m_textStream << i << "\t"
+                         << x->frequency << "\t"
+                         << x->amplitude<< "\t"
+                         << x->phase << "\n";
+#endif
+    }
+}
+
+bool SpectrumAnalyser::isReady() const
+{
+    return (Idle == m_state);
+}
+
+void SpectrumAnalyser::cancelCalculation()
+{
+    if (Busy == m_state)
+        m_state = Cancelled;
+}
+
+
+//-----------------------------------------------------------------------------
+// Private slots
+//-----------------------------------------------------------------------------
+
+void SpectrumAnalyser::calculationComplete(const FrequencySpectrum &spectrum)
+{
+    Q_ASSERT(Idle != m_state);
+    if (Busy == m_state)
+        emit spectrumChanged(spectrum);
+    m_state = Idle;
+}
+
+
+
+
diff --git a/demos/spectrum/app/spectrumanalyser.h b/demos/spectrum/app/spectrumanalyser.h
new file mode 100644
index 0000000..9d7684a
--- /dev/null
+++ b/demos/spectrum/app/spectrumanalyser.h
@@ -0,0 +1,188 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+#ifndef SPECTRUMANALYSER_H
+#define SPECTRUMANALYSER_H
+
+#include <QByteArray>
+#include <QObject>
+#include <QVector>
+
+#ifdef DUMP_SPECTRUMANALYSER
+#include <QDir>
+#include <QFile>
+#include <QTextStream>
+#endif
+
+#include "frequencyspectrum.h"
+#include "spectrum.h"
+
+#ifndef DISABLE_FFT
+#include "FFTRealFixLenParam.h"
+#endif
+
+class QAudioFormat;
+class QThread;
+class FFTRealWrapper;
+
+class SpectrumAnalyserThreadPrivate;
+
+/**
+ * Implementation of the spectrum analysis which can be run in a
+ * separate thread.
+ */
+class SpectrumAnalyserThread : public QObject
+{
+    Q_OBJECT
+public:
+    SpectrumAnalyserThread(QObject *parent);
+    ~SpectrumAnalyserThread();
+
+public slots:
+    void setWindowFunction(WindowFunction type);
+    void calculateSpectrum(const QByteArray &buffer,
+                           int inputFrequency,
+                           int bytesPerSample);
+
+signals:
+    void calculationComplete(const FrequencySpectrum &spectrum);
+
+private:
+    void calculateWindow();
+
+private:
+#ifndef DISABLE_FFT
+    FFTRealWrapper*                             m_fft;
+#endif
+
+    const int                                   m_numSamples;
+
+    WindowFunction                              m_windowFunction;
+
+#ifdef DISABLE_FFT
+    typedef qreal                               DataType;
+#else
+    typedef FFTRealFixLenParam::DataType        DataType;
+#endif
+    QVector<DataType>                           m_window;
+
+    QVector<DataType>                           m_input;
+    QVector<DataType>                           m_output;
+
+    FrequencySpectrum                           m_spectrum;
+
+#ifdef SPECTRUM_ANALYSER_SEPARATE_THREAD
+    QThread*                                    m_thread;
+#endif
+};
+
+/**
+ * Class which performs frequency spectrum analysis on a window of
+ * audio samples, provided to it by the Engine.
+ */
+class SpectrumAnalyser : public QObject
+{
+    Q_OBJECT
+public:
+    SpectrumAnalyser(QObject *parent = 0);
+    ~SpectrumAnalyser();
+
+#ifdef DUMP_SPECTRUMANALYSER
+    void setOutputPath(const QString &outputPath);
+#endif
+
+public:
+    /*
+     * Set the windowing function which is applied before calculating the FFT
+     */
+    void setWindowFunction(WindowFunction type);
+
+    /*
+     * Calculate a frequency spectrum
+     *
+     * \param buffer       Audio data
+     * \param format       Format of audio data
+     *
+     * Frequency spectrum is calculated asynchronously.  The result is returned
+     * via the spectrumChanged signal.
+     *
+     * An ongoing calculation can be cancelled by calling cancelCalculation().
+     *
+     */
+    void calculate(const QByteArray &buffer, const QAudioFormat &format);
+
+    /*
+     * Check whether the object is ready to perform another calculation
+     */
+    bool isReady() const;
+
+    /*
+     * Cancel an ongoing calculation
+     *
+     * Note that cancelling is asynchronous.
+     */
+    void cancelCalculation();
+
+signals:
+    void spectrumChanged(const FrequencySpectrum &spectrum);
+
+private slots:
+    void calculationComplete(const FrequencySpectrum &spectrum);
+
+private:
+    void calculateWindow();
+
+private:
+
+    SpectrumAnalyserThread*    m_thread;
+
+    enum State {
+        Idle,
+        Busy,
+        Cancelled
+    };
+
+    State              m_state;
+
+#ifdef DUMP_SPECTRUMANALYSER
+    QDir                m_outputDir;
+    int                 m_count;
+    QFile               m_textFile;
+    QTextStream         m_textStream;
+#endif
+};
+
+#endif // SPECTRUMANALYSER_H
+
diff --git a/demos/spectrum/app/tonegenerator.cpp b/demos/spectrum/app/tonegenerator.cpp
new file mode 100644
index 0000000..6458a7d
--- /dev/null
+++ b/demos/spectrum/app/tonegenerator.cpp
@@ -0,0 +1,92 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "spectrum.h"
+#include "utils.h"
+#include <QByteArray>
+#include <QtMultimedia/QAudioFormat>
+#include <QtCore/qmath.h>
+#include <QtCore/qendian.h>
+
+void generateTone(const SweptTone &tone, const QAudioFormat &format, QByteArray &buffer)
+{
+    Q_ASSERT(isPCMS16LE(format));
+
+    const int channelBytes = format.sampleSize() / 8;
+    const int sampleBytes = format.channels() * channelBytes;
+    int length = buffer.size();
+    const int numSamples = buffer.size() / sampleBytes;
+
+    Q_ASSERT(length % sampleBytes == 0);
+    Q_UNUSED(sampleBytes) // suppress warning in release builds
+
+    unsigned char *ptr = reinterpret_cast<unsigned char *>(buffer.data());
+
+    qreal phase = 0.0;
+
+    const qreal d = 2 * M_PI / format.frequency();
+
+    // We can't generate a zero-frequency sine wave
+    const qreal startFreq = tone.startFreq ? tone.startFreq : 1.0;
+
+    // Amount by which phase increases on each sample
+    qreal phaseStep = d * startFreq;
+
+    // Amount by which phaseStep increases on each sample
+    // If this is non-zero, the output is a frequency-swept tone
+    const qreal phaseStepStep = d * (tone.endFreq - startFreq) / numSamples;
+
+    while (length) {
+        const qreal x = tone.amplitude * qSin(phase);
+        const qint16 value = realToPcm(x);
+        for (int i=0; i<format.channels(); ++i) {
+            qToLittleEndian<qint16>(value, ptr);
+            ptr += channelBytes;
+            length -= channelBytes;
+        }
+
+        phase += phaseStep;
+        while (phase > 2 * M_PI)
+            phase -= 2 * M_PI;
+        phaseStep += phaseStepStep;
+    }
+}
+
diff --git a/demos/spectrum/app/tonegenerator.h b/demos/spectrum/app/tonegenerator.h
new file mode 100644
index 0000000..05d4c17
--- /dev/null
+++ b/demos/spectrum/app/tonegenerator.h
@@ -0,0 +1,51 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+#ifndef TONEGENERATOR_H
+#define TONEGENERATOR_H
+
+#include <QtCore/qglobal.h>
+#include "spectrum.h"
+
+class QAudioFormat;
+class QByteArray;
+
+/**
+ * Generate a sine wave
+ */
+void generateTone(const SweptTone &tone, const QAudioFormat &format, QByteArray &buffer);
+
+#endif // TONEGENERATOR_H
+
diff --git a/demos/spectrum/app/tonegeneratordialog.cpp b/demos/spectrum/app/tonegeneratordialog.cpp
new file mode 100644
index 0000000..06e453c
--- /dev/null
+++ b/demos/spectrum/app/tonegeneratordialog.cpp
@@ -0,0 +1,148 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "tonegeneratordialog.h"
+#include <QComboBox>
+#include <QDialogButtonBox>
+#include <QLabel>
+#include <QPushButton>
+#include <QVBoxLayout>
+#include <QCheckBox>
+#include <QSlider>
+#include <QSpinBox>
+
+const int ToneGeneratorFreqMin = 1;
+const int ToneGeneratorFreqMax = 1000;
+const int ToneGeneratorFreqDefault = 440;
+const int ToneGeneratorAmplitudeDefault = 75;
+
+ToneGeneratorDialog::ToneGeneratorDialog(QWidget *parent)
+    :   QDialog(parent)
+    ,   m_toneGeneratorSweepCheckBox(new QCheckBox(tr("Frequency sweep"), this))
+    ,   m_frequencySweepEnabled(true)
+    ,   m_toneGeneratorControl(new QWidget(this))
+    ,   m_toneGeneratorFrequencyControl(new QWidget(this))
+    ,   m_frequencySlider(new QSlider(Qt::Horizontal, this))
+    ,   m_frequencySpinBox(new QSpinBox(this))
+    ,   m_frequency(ToneGeneratorFreqDefault)
+    ,   m_amplitudeSlider(new QSlider(Qt::Horizontal, this))
+{
+    QVBoxLayout *dialogLayout = new QVBoxLayout(this);
+
+    m_toneGeneratorSweepCheckBox->setChecked(true);
+
+    // Configure tone generator controls
+    m_frequencySlider->setRange(ToneGeneratorFreqMin, ToneGeneratorFreqMax);
+    m_frequencySlider->setValue(ToneGeneratorFreqDefault);
+    m_frequencySpinBox->setRange(ToneGeneratorFreqMin, ToneGeneratorFreqMax);
+    m_frequencySpinBox->setValue(ToneGeneratorFreqDefault);
+    m_amplitudeSlider->setRange(0, 100);
+    m_amplitudeSlider->setValue(ToneGeneratorAmplitudeDefault);
+
+    // Add widgets to layout
+
+    QScopedPointer<QGridLayout> frequencyControlLayout(new QGridLayout);
+    QLabel *frequencyLabel = new QLabel(tr("Frequency (Hz)"), this);
+    frequencyControlLayout->addWidget(frequencyLabel, 0, 0, 2, 1);
+    frequencyControlLayout->addWidget(m_frequencySlider, 0, 1);
+    frequencyControlLayout->addWidget(m_frequencySpinBox, 1, 1);
+    m_toneGeneratorFrequencyControl->setLayout(frequencyControlLayout.data());
+    frequencyControlLayout.take(); // ownership transferred to m_toneGeneratorFrequencyControl
+    m_toneGeneratorFrequencyControl->setEnabled(false);
+
+    QScopedPointer<QGridLayout> toneGeneratorLayout(new QGridLayout);
+    QLabel *amplitudeLabel = new QLabel(tr("Amplitude"), this);
+    toneGeneratorLayout->addWidget(m_toneGeneratorSweepCheckBox, 0, 1);
+    toneGeneratorLayout->addWidget(m_toneGeneratorFrequencyControl, 1, 0, 1, 2);
+    toneGeneratorLayout->addWidget(amplitudeLabel, 2, 0);
+    toneGeneratorLayout->addWidget(m_amplitudeSlider, 2, 1);
+    m_toneGeneratorControl->setLayout(toneGeneratorLayout.data());
+    m_toneGeneratorControl->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
+    dialogLayout->addWidget(m_toneGeneratorControl);
+    toneGeneratorLayout.take(); // ownership transferred
+
+    // Connect
+    CHECKED_CONNECT(m_toneGeneratorSweepCheckBox, SIGNAL(toggled(bool)),
+                    this, SLOT(frequencySweepEnabled(bool)));
+    CHECKED_CONNECT(m_frequencySlider, SIGNAL(valueChanged(int)),
+                    m_frequencySpinBox, SLOT(setValue(int)));
+    CHECKED_CONNECT(m_frequencySpinBox, SIGNAL(valueChanged(int)),
+                    m_frequencySlider, SLOT(setValue(int)));
+
+    // Add standard buttons to layout
+    QDialogButtonBox *buttonBox = new QDialogButtonBox(this);
+    buttonBox->setStandardButtons(QDialogButtonBox::Ok | QDialogButtonBox::Cancel);
+    dialogLayout->addWidget(buttonBox);
+
+    // Connect standard buttons
+    CHECKED_CONNECT(buttonBox->button(QDialogButtonBox::Ok), SIGNAL(clicked()),
+                    this, SLOT(accept()));
+    CHECKED_CONNECT(buttonBox->button(QDialogButtonBox::Cancel), SIGNAL(clicked()),
+                    this, SLOT(reject()));
+
+    setLayout(dialogLayout);
+}
+
+ToneGeneratorDialog::~ToneGeneratorDialog()
+{
+
+}
+
+bool ToneGeneratorDialog::isFrequencySweepEnabled() const
+{
+    return m_toneGeneratorSweepCheckBox->isChecked();
+}
+
+qreal ToneGeneratorDialog::frequency() const
+{
+    return qreal(m_frequencySlider->value());
+}
+
+qreal ToneGeneratorDialog::amplitude() const
+{
+    return qreal(m_amplitudeSlider->value()) / 100.0;
+}
+
+void ToneGeneratorDialog::frequencySweepEnabled(bool enabled)
+{
+    m_frequencySweepEnabled = enabled;
+    m_toneGeneratorFrequencyControl->setEnabled(!enabled);
+}
diff --git a/demos/spectrum/app/tonegeneratordialog.h b/demos/spectrum/app/tonegeneratordialog.h
new file mode 100644
index 0000000..33b608d
--- /dev/null
+++ b/demos/spectrum/app/tonegeneratordialog.h
@@ -0,0 +1,76 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+#ifndef TONEGENERATORDIALOG_H
+#define TONEGENERATORDIALOG_H
+
+#include "spectrum.h"
+#include <QDialog>
+#include <QtMultimedia/QAudioDeviceInfo>
+
+class QCheckBox;
+class QSlider;
+class QSpinBox;
+class QGridLayout;
+
+/**
+ * Dialog which controls the parameters of the tone generator.
+ */
+class ToneGeneratorDialog : public QDialog {
+    Q_OBJECT
+public:
+    ToneGeneratorDialog(QWidget *parent = 0);
+    ~ToneGeneratorDialog();
+
+    bool isFrequencySweepEnabled() const;
+    qreal frequency() const;
+    qreal amplitude() const;
+
+private slots:
+    void frequencySweepEnabled(bool enabled);
+
+private:
+    QCheckBox*      m_toneGeneratorSweepCheckBox;
+    bool            m_frequencySweepEnabled;
+    QWidget*        m_toneGeneratorControl;
+    QWidget*        m_toneGeneratorFrequencyControl;
+    QSlider*        m_frequencySlider;
+    QSpinBox*       m_frequencySpinBox;
+    qreal           m_frequency;
+    QSlider*        m_amplitudeSlider;
+
+};
+
+#endif // TONEGENERATORDIALOG_H
diff --git a/demos/spectrum/app/utils.cpp b/demos/spectrum/app/utils.cpp
new file mode 100644
index 0000000..97dc6e3
--- /dev/null
+++ b/demos/spectrum/app/utils.cpp
@@ -0,0 +1,138 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtMultimedia/QAudioFormat>
+#include "utils.h"
+
+qint64 audioDuration(const QAudioFormat &format, qint64 bytes)
+{
+    return (bytes * 1000000) /
+        (format.frequency() * format.channels() * (format.sampleSize() / 8));
+}
+
+qint64 audioLength(const QAudioFormat &format, qint64 microSeconds)
+{
+   return (format.frequency() * format.channels() * (format.sampleSize() / 8))
+       * microSeconds / 1000000;
+}
+
+qreal nyquistFrequency(const QAudioFormat &format)
+{
+    return format.frequency() / 2;
+}
+
+QString formatToString(const QAudioFormat &format)
+{
+    QString result;
+
+    if (QAudioFormat() != format) {
+        if (format.codec() == "audio/pcm") {
+            Q_ASSERT(format.sampleType() == QAudioFormat::SignedInt);
+
+            const QString formatEndian = (format.byteOrder() == QAudioFormat::LittleEndian)
+                ?   QString("LE") : QString("BE");
+
+            QString formatType;
+            switch(format.sampleType()) {
+            case QAudioFormat::SignedInt:
+                formatType = "signed";
+                break;
+            case QAudioFormat::UnSignedInt:
+                formatType = "unsigned";
+                break;
+            case QAudioFormat::Float:
+                formatType = "float";
+                break;
+            case QAudioFormat::Unknown:
+                formatType = "unknown";
+                break;
+            }
+
+            QString formatChannels = QString("%1 channels").arg(format.channels());
+            switch (format.channels()) {
+            case 1:
+                formatChannels = "mono";
+                break;
+            case 2:
+                formatChannels = "stereo";
+                break;
+            }
+
+            result = QString("%1 Hz %2 bit %3 %4 %5")
+                .arg(format.frequency())
+                .arg(format.sampleSize())
+                .arg(formatType)
+                .arg(formatEndian)
+                .arg(formatChannels);
+        } else {
+            result = format.codec();
+        }
+    }
+
+    return result;
+}
+
+bool isPCM(const QAudioFormat &format)
+{
+    return (format.codec() == "audio/pcm");
+}
+
+
+bool isPCMS16LE(const QAudioFormat &format)
+{
+    return (isPCM(format) &&
+            format.sampleType() == QAudioFormat::SignedInt &&
+            format.sampleSize() == 16 &&
+            format.byteOrder() == QAudioFormat::LittleEndian);
+}
+
+const qint16  PCMS16MaxValue     =  32767;
+const quint16 PCMS16MaxAmplitude =  32768; // because minimum is -32768
+
+qreal pcmToReal(qint16 pcm)
+{
+    return qreal(pcm) / PCMS16MaxAmplitude;
+}
+
+qint16 realToPcm(qreal real)
+{
+    return real * PCMS16MaxValue;
+}
diff --git a/demos/spectrum/app/utils.h b/demos/spectrum/app/utils.h
new file mode 100644
index 0000000..cfa3633
--- /dev/null
+++ b/demos/spectrum/app/utils.h
@@ -0,0 +1,107 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+#ifndef UTILS_H
+#define UTILS_H
+
+#include <QtCore/qglobal.h>
+#include <QDebug>
+
+class QAudioFormat;
+
+//-----------------------------------------------------------------------------
+// Miscellaneous utility functions
+//-----------------------------------------------------------------------------
+
+qint64 audioDuration(const QAudioFormat &format, qint64 bytes);
+qint64 audioLength(const QAudioFormat &format, qint64 microSeconds);
+
+QString formatToString(const QAudioFormat &format);
+
+qreal nyquistFrequency(const QAudioFormat &format);
+
+// Scale PCM value to [-1.0, 1.0]
+qreal pcmToReal(qint16 pcm);
+
+// Scale real value in [-1.0, 1.0] to PCM
+qint16 realToPcm(qreal real);
+
+// Check whether the audio format is PCM
+bool isPCM(const QAudioFormat &format);
+
+// Check whether the audio format is signed, little-endian, 16-bit PCM
+bool isPCMS16LE(const QAudioFormat &format);
+
+// Compile-time calculation of powers of two
+
+template<int N> class PowerOfTwo
+{ public: static const int Result = PowerOfTwo<N-1>::Result * 2; };
+
+template<> class PowerOfTwo<0>
+{ public: static const int Result = 1; };
+
+
+//-----------------------------------------------------------------------------
+// Debug output
+//-----------------------------------------------------------------------------
+
+class NullDebug
+{
+public:
+    template <typename T>
+    NullDebug& operator<<(const T&) { return *this; }
+};
+
+inline NullDebug nullDebug() { return NullDebug(); }
+
+#ifdef LOG_ENGINE
+#   define ENGINE_DEBUG qDebug()
+#else
+#   define ENGINE_DEBUG nullDebug()
+#endif
+
+#ifdef LOG_SPECTRUMANALYSER
+#   define SPECTRUMANALYSER_DEBUG qDebug()
+#else
+#   define SPECTRUMANALYSER_DEBUG nullDebug()
+#endif
+
+#ifdef LOG_WAVEFORM
+#   define WAVEFORM_DEBUG qDebug()
+#else
+#   define WAVEFORM_DEBUG nullDebug()
+#endif
+
+#endif // UTILS_H
diff --git a/demos/spectrum/app/waveform.cpp b/demos/spectrum/app/waveform.cpp
new file mode 100644
index 0000000..3fc4f76
--- /dev/null
+++ b/demos/spectrum/app/waveform.cpp
@@ -0,0 +1,419 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "waveform.h"
+#include "utils.h"
+#include <QPainter>
+#include <QResizeEvent>
+#include <QDebug>
+
+
+Waveform::Waveform(const QByteArray &buffer, QWidget *parent)
+    :   QWidget(parent)
+    ,   m_buffer(buffer)
+    ,   m_dataLength(0)
+    ,   m_position(0)
+    ,   m_active(false)
+    ,   m_tileLength(0)
+    ,   m_tileArrayStart(0)
+    ,   m_windowPosition(0)
+    ,   m_windowLength(0)
+{
+    setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
+    setMinimumHeight(50);
+}
+
+Waveform::~Waveform()
+{
+    deletePixmaps();
+}
+
+void Waveform::paintEvent(QPaintEvent * /*event*/)
+{
+    QPainter painter(this);
+
+    painter.fillRect(rect(), Qt::black);
+
+    if (m_active) {
+        WAVEFORM_DEBUG << "Waveform::paintEvent"
+                       << "windowPosition" << m_windowPosition
+                       << "windowLength" << m_windowLength;
+        qint64 pos = m_windowPosition;
+        const qint64 windowEnd = m_windowPosition + m_windowLength;
+        int destLeft = 0;
+        int destRight = 0;
+        while (pos < windowEnd) {
+            const TilePoint point = tilePoint(pos);
+            WAVEFORM_DEBUG << "Waveform::paintEvent" << "pos" << pos
+                           << "tileIndex" << point.index
+                           << "positionOffset" << point.positionOffset
+                           << "pixelOffset" << point.pixelOffset;
+
+            if (point.index != NullIndex) {
+                const Tile &tile = m_tiles[point.index];
+                if (tile.painted) {
+                    const qint64 sectionLength = qMin((m_tileLength - point.positionOffset),
+                                                     (windowEnd - pos));
+                    Q_ASSERT(sectionLength > 0);
+
+                    const int sourceRight = tilePixelOffset(point.positionOffset + sectionLength);
+                    destRight = windowPixelOffset(pos - m_windowPosition + sectionLength);
+
+                    QRect destRect = rect();
+                    destRect.setLeft(destLeft);
+                    destRect.setRight(destRight);
+
+                    QRect sourceRect(QPoint(), m_pixmapSize);
+                    sourceRect.setLeft(point.pixelOffset);
+                    sourceRect.setRight(sourceRight);
+
+                    WAVEFORM_DEBUG << "Waveform::paintEvent" << "tileIndex" << point.index
+                                   << "source" << point.pixelOffset << sourceRight
+                                   << "dest" << destLeft << destRight;
+
+                    painter.drawPixmap(destRect, *tile.pixmap, sourceRect);
+
+                    destLeft = destRight;
+
+                    if (point.index < m_tiles.count()) {
+                        pos = tilePosition(point.index + 1);
+                        WAVEFORM_DEBUG << "Waveform::paintEvent" << "pos ->" << pos;
+                    } else {
+                        // Reached end of tile array
+                        WAVEFORM_DEBUG << "Waveform::paintEvent" << "reached end of tile array";
+                        break;
+                    }
+                } else {
+                    // Passed last tile which is painted
+                    WAVEFORM_DEBUG << "Waveform::paintEvent" << "tile" << point.index << "not painted";
+                    break;
+                }
+            } else {
+                // pos is past end of tile array
+                WAVEFORM_DEBUG << "Waveform::paintEvent" << "pos" << pos << "past end of tile array";
+                break;
+            }
+        }
+
+        WAVEFORM_DEBUG << "Waveform::paintEvent" << "final pos" << pos << "final x" << destRight;
+    }
+}
+
+void Waveform::resizeEvent(QResizeEvent *event)
+{
+    if (event->size() != event->oldSize())
+        createPixmaps(event->size());
+}
+
+void Waveform::initialize(const QAudioFormat &format, qint64 audioBufferSize, qint64 windowDurationUs)
+{
+    WAVEFORM_DEBUG << "Waveform::initialize"
+                   << "audioBufferSize" << audioBufferSize
+                   << "m_buffer.size()" << m_buffer.size()
+                   << "windowDurationUs" << windowDurationUs;
+
+    reset();
+
+    m_format = format;
+
+    // Calculate tile size
+    m_tileLength = audioBufferSize;
+
+    // Calculate window size
+    m_windowLength = audioLength(m_format, windowDurationUs);
+
+    // Calculate number of tiles required
+    int nTiles;
+    if (m_tileLength > m_windowLength) {
+        nTiles = 2;
+    } else {
+        nTiles = m_windowLength / m_tileLength + 1;
+        if (m_windowLength % m_tileLength)
+            ++nTiles;
+    }
+
+    WAVEFORM_DEBUG << "Waveform::initialize"
+                   << "tileLength" << m_tileLength
+                   << "windowLength" << m_windowLength
+                   << "nTiles" << nTiles;
+
+    m_pixmaps.fill(0, nTiles);
+    m_tiles.resize(nTiles);
+
+    createPixmaps(rect().size());
+
+    m_active = true;
+}
+
+void Waveform::reset()
+{
+    WAVEFORM_DEBUG << "Waveform::reset";
+
+    m_dataLength = 0;
+    m_position = 0;
+    m_format = QAudioFormat();
+    m_active = false;
+    deletePixmaps();
+    m_tiles.clear();
+    m_tileLength = 0;
+    m_tileArrayStart = 0;
+    m_windowPosition = 0;
+    m_windowLength = 0;
+}
+
+void Waveform::dataLengthChanged(qint64 length)
+{
+    WAVEFORM_DEBUG << "Waveform::dataLengthChanged" << length;
+    const qint64 oldLength = m_dataLength;
+    m_dataLength = length;
+
+    if (m_active) {
+        if (m_dataLength < oldLength)
+            positionChanged(m_dataLength);
+        else
+            paintTiles();
+    }
+}
+
+void Waveform::positionChanged(qint64 position)
+{
+    WAVEFORM_DEBUG << "Waveform::positionChanged" << position;
+
+    if (position + m_windowLength > m_dataLength)
+        position = m_dataLength - m_windowLength;
+
+    m_position = position;
+
+    setWindowPosition(position);
+}
+
+void Waveform::deletePixmaps()
+{
+    QPixmap *pixmap;
+    foreach (pixmap, m_pixmaps)
+        delete pixmap;
+    m_pixmaps.clear();
+}
+
+void Waveform::createPixmaps(const QSize &widgetSize)
+{
+    m_pixmapSize = widgetSize;
+    m_pixmapSize.setWidth(qreal(widgetSize.width()) * m_tileLength / m_windowLength);
+
+    WAVEFORM_DEBUG << "Waveform::createPixmaps"
+                   << "widgetSize" << widgetSize
+                   << "pixmapSize" << m_pixmapSize;
+
+    Q_ASSERT(m_tiles.count() == m_pixmaps.count());
+
+    // (Re)create pixmaps
+    for (int i=0; i<m_pixmaps.size(); ++i) {
+        delete m_pixmaps[i];
+        m_pixmaps[i] = 0;
+        m_pixmaps[i] = new QPixmap(m_pixmapSize);
+    }
+
+    // Update tile pixmap pointers, and mark for repainting
+    for (int i=0; i<m_tiles.count(); ++i) {
+        m_tiles[i].pixmap = m_pixmaps[i];
+        m_tiles[i].painted = false;
+    }
+
+    paintTiles();
+}
+
+void Waveform::setWindowPosition(qint64 position)
+{
+    WAVEFORM_DEBUG << "Waveform::setWindowPosition"
+                   << "old" << m_windowPosition << "new" << position
+                   << "tileArrayStart" << m_tileArrayStart;
+
+    const qint64 oldPosition = m_windowPosition;
+    m_windowPosition = position;
+
+    if((m_windowPosition >= oldPosition) &&
+        (m_windowPosition - m_tileArrayStart < (m_tiles.count() * m_tileLength))) {
+        // Work out how many tiles need to be shuffled
+        const qint64 offset = m_windowPosition - m_tileArrayStart;
+        const int nTiles = offset / m_tileLength;
+        shuffleTiles(nTiles);
+    } else {
+        resetTiles(m_windowPosition);
+    }
+
+    if(!paintTiles() && m_windowPosition != oldPosition)
+        update();
+}
+
+qint64 Waveform::tilePosition(int index) const
+{
+    return m_tileArrayStart + index * m_tileLength;
+}
+
+Waveform::TilePoint Waveform::tilePoint(qint64 position) const
+{
+    TilePoint result;
+    if (position >= m_tileArrayStart) {
+        const qint64 tileArrayEnd = m_tileArrayStart + m_tiles.count() * m_tileLength;
+        if (position < tileArrayEnd) {
+            const qint64 offsetIntoTileArray = position - m_tileArrayStart;
+            result.index = offsetIntoTileArray / m_tileLength;
+            Q_ASSERT(result.index >= 0 && result.index <= m_tiles.count());
+            result.positionOffset = offsetIntoTileArray % m_tileLength;
+            result.pixelOffset = tilePixelOffset(result.positionOffset);
+            Q_ASSERT(result.pixelOffset >= 0 && result.pixelOffset <= m_pixmapSize.width());
+        }
+    }
+
+    return result;
+}
+
+int Waveform::tilePixelOffset(qint64 positionOffset) const
+{
+    Q_ASSERT(positionOffset >= 0 && positionOffset <= m_tileLength);
+    const int result = (qreal(positionOffset) / m_tileLength) * m_pixmapSize.width();
+    return result;
+}
+
+int Waveform::windowPixelOffset(qint64 positionOffset) const
+{
+    Q_ASSERT(positionOffset >= 0 && positionOffset <= m_windowLength);
+    const int result = (qreal(positionOffset) / m_windowLength) * rect().width();
+    return result;
+}
+
+bool Waveform::paintTiles()
+{
+    WAVEFORM_DEBUG << "Waveform::paintTiles";
+    bool updateRequired = false;
+
+    for (int i=0; i<m_tiles.count(); ++i) {
+        const Tile &tile = m_tiles[i];
+        if (!tile.painted) {
+            const qint64 tileEnd = m_tileArrayStart + (i + 1) * m_tileLength;
+            if (m_dataLength >= tileEnd) {
+                paintTile(i);
+                updateRequired = true;
+            }
+        }
+    }
+
+    if (updateRequired)
+        update();
+
+    return updateRequired;
+}
+
+void Waveform::paintTile(int index)
+{
+    WAVEFORM_DEBUG << "Waveform::paintTile" << "index" << index;
+
+    const qint64 tileStart = m_tileArrayStart + index * m_tileLength;
+    Q_ASSERT(m_dataLength >= tileStart + m_tileLength);
+
+    Tile &tile = m_tiles[index];
+    Q_ASSERT(!tile.painted);
+
+    const qint16* base = reinterpret_cast<const qint16*>(m_buffer.constData());
+    const qint16* buffer = base + (tileStart / 2);
+    const int numSamples = m_tileLength / (2 * m_format.channels());
+
+    QPainter painter(tile.pixmap);
+
+    painter.fillRect(tile.pixmap->rect(), Qt::black);
+
+    QPen pen(Qt::white);
+    painter.setPen(pen);
+
+    // Calculate initial PCM value
+    qint16 previousPcmValue = 0;
+    if (buffer > base)
+        previousPcmValue = *(buffer - m_format.channels());
+
+    // Calculate initial point
+    const qreal previousRealValue = pcmToReal(previousPcmValue);
+    const int originY = ((previousRealValue + 1.0) / 2) * m_pixmapSize.height();
+    const QPoint origin(0, originY);
+
+    QLine line(origin, origin);
+
+    for (int i=0; i<numSamples; ++i) {
+        const qint16* ptr = buffer + i * m_format.channels();
+        const qint16 pcmValue = *ptr;
+        const qreal realValue = pcmToReal(pcmValue);
+
+        const int x = tilePixelOffset(i * 2 * m_format.channels());
+        const int y = ((realValue + 1.0) / 2) * m_pixmapSize.height();
+
+        line.setP2(QPoint(x, y));
+        painter.drawLine(line);
+        line.setP1(line.p2());
+    }
+
+    tile.painted = true;
+}
+
+void Waveform::shuffleTiles(int n)
+{
+    WAVEFORM_DEBUG << "Waveform::shuffleTiles" << "n" << n;
+
+    while (n--) {
+        Tile tile = m_tiles.first();
+        tile.painted = false;
+        m_tiles.erase(m_tiles.begin());
+        m_tiles += tile;
+        m_tileArrayStart += m_tileLength;
+    }
+
+    WAVEFORM_DEBUG << "Waveform::shuffleTiles" << "tileArrayStart" << m_tileArrayStart;
+}
+
+void Waveform::resetTiles(qint64 newStartPos)
+{
+    WAVEFORM_DEBUG << "Waveform::resetTiles" << "newStartPos" << newStartPos;
+
+    QVector<Tile>::iterator i = m_tiles.begin();
+    for ( ; i != m_tiles.end(); ++i)
+        i->painted = false;
+
+    m_tileArrayStart = newStartPos;
+}
+
diff --git a/demos/spectrum/app/waveform.h b/demos/spectrum/app/waveform.h
new file mode 100644
index 0000000..e5cde5c
--- /dev/null
+++ b/demos/spectrum/app/waveform.h
@@ -0,0 +1,196 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+#ifndef WAVEFORM_H
+#define WAVEFORM_H
+
+#include <QWidget>
+#include <QtMultimedia/QAudioFormat>
+#include <QPixmap>
+#include <QScopedPointer>
+
+class QByteArray;
+
+/**
+ * Widget which displays a section of the audio waveform.
+ *
+ * The waveform is rendered on a set of QPixmaps which form a group of tiles
+ * whose extent covers the widget.  As the audio position is updated, these
+ * tiles are scrolled from left to right; when the left-most tile scrolls
+ * outside the widget, it is moved to the right end of the tile array and
+ * painted with the next section of the waveform.
+ */
+class Waveform : public QWidget {
+    Q_OBJECT
+public:
+    Waveform(const QByteArray &buffer, QWidget *parent = 0);
+    ~Waveform();
+
+    // QWidget
+    void paintEvent(QPaintEvent *event);
+    void resizeEvent(QResizeEvent *event);
+
+    void initialize(const QAudioFormat &format, qint64 audioBufferSize, qint64 windowDurationUs);
+    void reset();
+
+    void setAutoUpdatePosition(bool enabled);
+
+public slots:
+    void dataLengthChanged(qint64 length);
+    void positionChanged(qint64 position);
+
+private:
+    static const int NullIndex = -1;
+
+    void deletePixmaps();
+
+    /*
+     * (Re)create all pixmaps, repaint and update the display.
+     * Triggers an update();
+     */
+    void createPixmaps(const QSize &newSize);
+
+    /*
+     * Update window position.
+     * Triggers an update().
+     */
+    void setWindowPosition(qint64 position);
+
+    /*
+     * Base position of tile
+     */
+    qint64 tilePosition(int index) const;
+
+    /*
+     * Structure which identifies a point within a given
+     * tile.
+     */
+    struct TilePoint
+    {
+        TilePoint(int idx = 0, qint64 pos = 0, qint64 pix = 0)
+        :   index(idx), positionOffset(pos), pixelOffset(pix)
+        { }
+
+        // Index of tile
+        int     index;
+
+        // Number of bytes from start of tile
+        qint64  positionOffset;
+
+        // Number of pixels from left of corresponding pixmap
+        int     pixelOffset;
+    };
+
+    /*
+     * Convert position in m_buffer into a tile index and an offset in pixels
+     * into the corresponding pixmap.
+     *
+     * \param position  Offset into m_buffer, in bytes
+
+     * If position is outside the tile array, index is NullIndex and
+     * offset is zero.
+     */
+    TilePoint tilePoint(qint64 position) const;
+
+    /*
+     * Convert offset in bytes into a tile into an offset in pixels
+     * within that tile.
+     */
+    int tilePixelOffset(qint64 positionOffset) const;
+
+    /*
+     * Convert offset in bytes into the window into an offset in pixels
+     * within the widget rect().
+     */
+    int windowPixelOffset(qint64 positionOffset) const;
+
+    /*
+     * Paint all tiles which can be painted.
+     * \return true iff update() was called
+     */
+    bool paintTiles();
+
+    /*
+     * Paint the specified tile
+     *
+     * \pre Sufficient data is available to completely paint the tile, i.e.
+     *      m_dataLength is greater than the upper bound of the tile.
+     */
+    void paintTile(int index);
+
+    /*
+     * Move the first n tiles to the end of the array, and mark them as not
+     * painted.
+     */
+    void shuffleTiles(int n);
+
+    /*
+     * Reset tile array
+     */
+    void resetTiles(qint64 newStartPos);
+
+private:
+    const QByteArray&       m_buffer;
+    qint64                  m_dataLength;
+    qint64                  m_position;
+    QAudioFormat            m_format;
+
+    bool                    m_active;
+
+    QSize                   m_pixmapSize;
+    QVector<QPixmap*>       m_pixmaps;
+
+    struct Tile {
+        // Pointer into parent m_pixmaps array
+        QPixmap*            pixmap;
+
+        // Flag indicating whether this tile has been painted
+        bool                painted;
+    };
+
+    QVector<Tile>           m_tiles;
+
+    // Length of audio data in bytes depicted by each tile
+    qint64                  m_tileLength;
+
+    // Position in bytes of the first tile, relative to m_buffer
+    qint64                  m_tileArrayStart;
+
+    qint64                  m_windowPosition;
+    qint64                  m_windowLength;
+
+};
+
+#endif // WAVEFORM_H
diff --git a/demos/spectrum/app/wavfile.cpp b/demos/spectrum/app/wavfile.cpp
new file mode 100644
index 0000000..163e5ee
--- /dev/null
+++ b/demos/spectrum/app/wavfile.cpp
@@ -0,0 +1,247 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This device is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This device contains pre-release code and may not be distributed.
+** You may use this device in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this device may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the device LICENSE.LGPL included in the
+** packaging of this device.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the device LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this device, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtCore/qendian.h>
+#include <QVector>
+#include <QDebug>
+#include "utils.h"
+#include "wavfile.h"
+
+struct chunk
+{
+    char        id[4];
+    quint32     size;
+};
+
+struct RIFFHeader
+{
+    chunk       descriptor;     // "RIFF"
+    char        type[4];        // "WAVE"
+};
+
+struct WAVEHeader
+{
+    chunk       descriptor;
+    quint16     audioFormat;
+    quint16     numChannels;
+    quint32     sampleRate;
+    quint32     byteRate;
+    quint16     blockAlign;
+    quint16     bitsPerSample;
+};
+
+struct DATAHeader
+{
+    chunk       descriptor;
+};
+
+struct CombinedHeader
+{
+    RIFFHeader  riff;
+    WAVEHeader  wave;
+    DATAHeader  data;
+};
+
+static const int HeaderLength = sizeof(CombinedHeader);
+
+
+WavFile::WavFile(const QAudioFormat &format, qint64 dataLength)
+    :   m_format(format)
+    ,   m_dataLength(dataLength)
+{
+
+}
+
+bool WavFile::readHeader(QIODevice &device)
+{
+    bool result = true;
+
+    if (!device.isSequential())
+        result = device.seek(0);
+    // else, assume that current position is the start of the header
+
+    if (result) {
+        CombinedHeader header;
+        result = (device.read(reinterpret_cast<char *>(&header), HeaderLength) == HeaderLength);
+        if (result) {
+            if ((memcmp(&header.riff.descriptor.id, "RIFF", 4) == 0
+                || memcmp(&header.riff.descriptor.id, "RIFX", 4) == 0)
+                && memcmp(&header.riff.type, "WAVE", 4) == 0
+                && memcmp(&header.wave.descriptor.id, "fmt ", 4) == 0
+                && header.wave.audioFormat == 1 // PCM
+            ) {
+                if (memcmp(&header.riff.descriptor.id, "RIFF", 4) == 0)
+                    m_format.setByteOrder(QAudioFormat::LittleEndian);
+                else
+                    m_format.setByteOrder(QAudioFormat::BigEndian);
+
+                m_format.setChannels(qFromLittleEndian<quint16>(header.wave.numChannels));
+                m_format.setCodec("audio/pcm");
+                m_format.setFrequency(qFromLittleEndian<quint32>(header.wave.sampleRate));
+                m_format.setSampleSize(qFromLittleEndian<quint16>(header.wave.bitsPerSample));
+
+                switch(header.wave.bitsPerSample) {
+                case 8:
+                    m_format.setSampleType(QAudioFormat::UnSignedInt);
+                    break;
+                case 16:
+                    m_format.setSampleType(QAudioFormat::SignedInt);
+                    break;
+                default:
+                    result = false;
+                }
+
+                m_dataLength = device.size() - HeaderLength;
+            } else {
+                result = false;
+            }
+        }
+    }
+
+    return result;
+}
+
+bool WavFile::writeHeader(QIODevice &device)
+{
+    CombinedHeader header;
+
+    memset(&header, 0, HeaderLength);
+
+    // RIFF header
+    if (m_format.byteOrder() == QAudioFormat::LittleEndian)
+        strncpy(&header.riff.descriptor.id[0], "RIFF", 4);
+    else
+        strncpy(&header.riff.descriptor.id[0], "RIFX", 4);
+    qToLittleEndian<quint32>(quint32(m_dataLength + HeaderLength - 8),
+                             reinterpret_cast<unsigned char*>(&header.riff.descriptor.size));
+    strncpy(&header.riff.type[0], "WAVE", 4);
+
+    // WAVE header
+    strncpy(&header.wave.descriptor.id[0], "fmt ", 4);
+    qToLittleEndian<quint32>(quint32(16),
+                             reinterpret_cast<unsigned char*>(&header.wave.descriptor.size));
+    qToLittleEndian<quint16>(quint16(1),
+                             reinterpret_cast<unsigned char*>(&header.wave.audioFormat));
+    qToLittleEndian<quint16>(quint16(m_format.channels()),
+                             reinterpret_cast<unsigned char*>(&header.wave.numChannels));
+    qToLittleEndian<quint32>(quint32(m_format.frequency()),
+                             reinterpret_cast<unsigned char*>(&header.wave.sampleRate));
+    qToLittleEndian<quint32>(quint32(m_format.frequency() * m_format.channels() * m_format.sampleSize() / 8),
+                             reinterpret_cast<unsigned char*>(&header.wave.byteRate));
+    qToLittleEndian<quint16>(quint16(m_format.channels() * m_format.sampleSize() / 8),
+                             reinterpret_cast<unsigned char*>(&header.wave.blockAlign));
+    qToLittleEndian<quint16>(quint16(m_format.sampleSize()),
+                             reinterpret_cast<unsigned char*>(&header.wave.bitsPerSample));
+
+    // DATA header
+    strncpy(&header.data.descriptor.id[0], "data", 4);
+    qToLittleEndian<quint32>(quint32(m_dataLength),
+                             reinterpret_cast<unsigned char*>(&header.data.descriptor.size));
+
+    return (device.write(reinterpret_cast<const char *>(&header), HeaderLength) == HeaderLength);
+}
+
+const QAudioFormat& WavFile::format() const
+{
+    return m_format;
+}
+
+qint64 WavFile::dataLength() const
+{
+    return m_dataLength;
+}
+
+qint64 WavFile::headerLength()
+{
+    return HeaderLength;
+}
+
+bool WavFile::writeDataLength(QIODevice &device, qint64 dataLength)
+{
+    bool result = false;
+    if (!device.isSequential()) {
+        device.seek(40);
+        unsigned char dataLengthLE[4];
+        qToLittleEndian<quint32>(quint32(dataLength), dataLengthLE);
+        result = (device.write(reinterpret_cast<const char *>(dataLengthLE), 4) == 4);
+    }
+    return result;
+}
+
+#include <QFile>
+#include <QTextStream>
+
+qint64 WavFile::readData(QIODevice &device, QByteArray &buffer,
+                         QAudioFormat outputFormat)
+{
+    if (QAudioFormat() == outputFormat)
+        outputFormat = m_format;
+
+    qint64 result = 0;
+
+    QFile file("wav.txt");
+    file.open(QIODevice::WriteOnly | QIODevice::Text);
+    QTextStream stream;
+    stream.setDevice(&file);
+
+    if (isPCMS16LE(outputFormat) && isPCMS16LE(m_format)) {
+        QVector<char> inputSample(2 * m_format.channels());
+
+        qint16 *output = reinterpret_cast<qint16*>(buffer.data());
+
+        while (result < buffer.size()) {
+            if (device.read(inputSample.data(), inputSample.count())) {
+                int inputIdx = 0;
+                for (int outputIdx = 0; outputIdx < outputFormat.channels(); ++outputIdx) {
+                    const qint16* input = reinterpret_cast<const qint16*>(inputSample.data() + 2 * inputIdx);
+                    *output++ = qFromLittleEndian<qint16>(*input);
+                    result += 2;
+                    if (inputIdx < m_format.channels())
+                        ++inputIdx;
+                }
+            } else {
+                break;
+            }
+        }
+    }
+    return result;
+}
+
diff --git a/demos/spectrum/app/wavfile.h b/demos/spectrum/app/wavfile.h
new file mode 100644
index 0000000..d8c54fa
--- /dev/null
+++ b/demos/spectrum/app/wavfile.h
@@ -0,0 +1,78 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** You may use this file under the terms of the BSD license as follows:
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are met:
+** - Redistributions of source code must retain the above copyright notice,
+**   this list of conditions and the following disclaimer.
+** - Redistributions in binary form must reproduce the above copyright notice,
+**   this list of conditions and the following disclaimer in the documentation
+**   and/or other materials provided with the distribution.
+** - Neither the name of Nokia Corporation and its Subsidiary(-ies) nor the
+**   names of its contributors may be used to endorse or promote products
+**   derived from this software without specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+** POSSIBILITY OF SUCH DAMAGE.
+**
+*****************************************************************************/
+
+
+#ifndef WAVFILE_H
+#define WAVFILE_H
+
+#include <QtCore/qobject.h>
+#include <QtCore/qfile.h>
+#include <QtMultimedia/qaudioformat.h>
+
+/**
+ * Helper class for reading WAV files
+ *
+ * See https://ccrma.stanford.edu/courses/422/projects/WaveFormat/
+ */
+class WavFile
+{
+public:
+    WavFile(const QAudioFormat &format = QAudioFormat(),
+              qint64 dataLength = 0);
+
+    // Reads WAV header and seeks to start of data
+    bool readHeader(QIODevice &device);
+
+    // Writes WAV header
+    bool writeHeader(QIODevice &device);
+
+    // Read PCM data
+    qint64 readData(QIODevice &device, QByteArray &buffer,
+                    QAudioFormat outputFormat = QAudioFormat());
+
+    const QAudioFormat& format() const;
+    qint64 dataLength() const;
+
+    static qint64 headerLength();
+
+    static bool writeDataLength(QIODevice &device, qint64 dataLength);
+
+private:
+    QAudioFormat m_format;
+    qint64 m_dataLength;
+};
+
+#endif
+
diff --git a/demos/spectrum/fftreal/Array.h b/demos/spectrum/fftreal/Array.h
new file mode 100644
index 0000000..a08e3cf
--- /dev/null
+++ b/demos/spectrum/fftreal/Array.h
@@ -0,0 +1,97 @@
+/*****************************************************************************
+
+        Array.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (Array_HEADER_INCLUDED)
+#define	Array_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class T, long LEN>
+class Array
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+	typedef	T	DataType;
+
+						Array ();
+
+	inline const DataType &
+						operator [] (long pos) const;
+	inline DataType &
+						operator [] (long pos);
+
+	static inline long
+						size ();
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+	DataType			_data_arr [LEN];
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						Array (const Array &other);
+	Array &			operator = (const Array &other);
+	bool				operator == (const Array &other);
+	bool				operator != (const Array &other);
+
+};	// class Array
+
+
+
+#include	"Array.hpp"
+
+
+
+#endif	// Array_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/Array.hpp b/demos/spectrum/fftreal/Array.hpp
new file mode 100644
index 0000000..8300077
--- /dev/null
+++ b/demos/spectrum/fftreal/Array.hpp
@@ -0,0 +1,98 @@
+/*****************************************************************************
+
+        Array.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (Array_CURRENT_CODEHEADER)
+	#error Recursive inclusion of Array code header.
+#endif
+#define	Array_CURRENT_CODEHEADER
+
+#if ! defined (Array_CODEHEADER_INCLUDED)
+#define	Array_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	<cassert>
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class T, long LEN>
+Array <T, LEN>::Array ()
+{
+	// Nothing
+}
+
+
+
+template <class T, long LEN>
+const typename Array <T, LEN>::DataType &	Array <T, LEN>::operator [] (long pos) const
+{
+	assert (pos >= 0);
+	assert (pos < LEN);
+
+	return (_data_arr [pos]);
+}
+
+
+
+template <class T, long LEN>
+typename Array <T, LEN>::DataType &	Array <T, LEN>::operator [] (long pos)
+{
+	assert (pos >= 0);
+	assert (pos < LEN);
+
+	return (_data_arr [pos]);
+}
+
+
+
+template <class T, long LEN>
+long	Array <T, LEN>::size ()
+{
+	return (LEN);
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+#endif	// Array_CODEHEADER_INCLUDED
+
+#undef Array_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/DynArray.h b/demos/spectrum/fftreal/DynArray.h
new file mode 100644
index 0000000..8041a0c
--- /dev/null
+++ b/demos/spectrum/fftreal/DynArray.h
@@ -0,0 +1,100 @@
+/*****************************************************************************
+
+        DynArray.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (DynArray_HEADER_INCLUDED)
+#define	DynArray_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class T>
+class DynArray
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+	typedef	T	DataType;
+
+						DynArray ();
+	explicit			DynArray (long size);
+						~DynArray ();
+
+	inline long		size () const;
+	inline void		resize (long size);
+
+	inline const DataType &
+						operator [] (long pos) const;
+	inline DataType &
+						operator [] (long pos);
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+	DataType *		_data_ptr;
+	long				_len;
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						DynArray (const DynArray &other);
+	DynArray &		operator = (const DynArray &other);
+	bool				operator == (const DynArray &other);
+	bool				operator != (const DynArray &other);
+
+};	// class DynArray
+
+
+
+#include	"DynArray.hpp"
+
+
+
+#endif	// DynArray_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/DynArray.hpp b/demos/spectrum/fftreal/DynArray.hpp
new file mode 100644
index 0000000..e62b10f
--- /dev/null
+++ b/demos/spectrum/fftreal/DynArray.hpp
@@ -0,0 +1,143 @@
+/*****************************************************************************
+
+        DynArray.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (DynArray_CURRENT_CODEHEADER)
+	#error Recursive inclusion of DynArray code header.
+#endif
+#define	DynArray_CURRENT_CODEHEADER
+
+#if ! defined (DynArray_CODEHEADER_INCLUDED)
+#define	DynArray_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	<cassert>
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class T>
+DynArray <T>::DynArray ()
+:	_data_ptr (0)
+,	_len (0)
+{
+	// Nothing
+}
+
+
+
+template <class T>
+DynArray <T>::DynArray (long size)
+:	_data_ptr (0)
+,	_len (0)
+{
+	assert (size >= 0);
+	if (size > 0)
+	{
+		_data_ptr = new DataType [size];
+		_len = size;
+	}
+}
+
+
+
+template <class T>
+DynArray <T>::~DynArray ()
+{
+	delete [] _data_ptr;
+	_data_ptr = 0;
+	_len = 0;
+}
+
+
+
+template <class T>
+long	DynArray <T>::size () const
+{
+	return (_len);
+}
+
+
+
+template <class T>
+void	DynArray <T>::resize (long size)
+{
+	assert (size >= 0);
+	if (size > 0)
+	{
+		DataType *		old_data_ptr = _data_ptr;
+		DataType *		tmp_data_ptr = new DataType [size];
+
+		_data_ptr = tmp_data_ptr;
+		_len = size;
+
+		delete [] old_data_ptr;
+	}
+}
+
+
+
+template <class T>
+const typename DynArray <T>::DataType &	DynArray <T>::operator [] (long pos) const
+{
+	assert (pos >= 0);
+	assert (pos < _len);
+
+	return (_data_ptr [pos]);
+}
+
+
+
+template <class T>
+typename DynArray <T>::DataType &	DynArray <T>::operator [] (long pos)
+{
+	assert (pos >= 0);
+	assert (pos < _len);
+
+	return (_data_ptr [pos]);
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+#endif	// DynArray_CODEHEADER_INCLUDED
+
+#undef DynArray_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/FFTReal.dsp b/demos/spectrum/fftreal/FFTReal.dsp
new file mode 100644
index 0000000..fe970db
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTReal.dsp
@@ -0,0 +1,273 @@
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+# Microsoft Developer Studio Generated Build File, Format Version 6.00
+# ** DO NOT EDIT **
+
+# TARGTYPE "Win32 (x86) Console Application" 0x0103
+
+CFG=FFTReal - Win32 Debug
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+!MESSAGE use the Export Makefile command and run
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+!MESSAGE 
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+!MESSAGE "FFTReal - Win32 Release" (based on "Win32 (x86) Console Application")
+!MESSAGE "FFTReal - Win32 Debug" (based on "Win32 (x86) Console Application")
+!MESSAGE 
+
+# Begin Project
+# PROP AllowPerConfigDependencies 0
+# PROP Scc_ProjName ""
+# PROP Scc_LocalPath ""
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+
+!IF  "$(CFG)" == "FFTReal - Win32 Release"
+
+# PROP BASE Use_MFC 0
+# PROP BASE Use_Debug_Libraries 0
+# PROP BASE Output_Dir "Release"
+# PROP BASE Intermediate_Dir "Release"
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+
+!ELSEIF  "$(CFG)" == "FFTReal - Win32 Debug"
+
+# PROP BASE Use_MFC 0
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+# ADD BASE RSC /l 0x40c /d "_DEBUG"
+# ADD RSC /l 0x40c /d "_DEBUG"
+BSC32=bscmake.exe
+# ADD BASE BSC32 /nologo
+# ADD BSC32 /nologo
+LINK32=link.exe
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+# ADD LINK32 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /subsystem:console /debug /machine:I386 /pdbtype:sept
+
+!ENDIF 
+
+# Begin Target
+
+# Name "FFTReal - Win32 Release"
+# Name "FFTReal - Win32 Debug"
+# Begin Group "Library"
+
+# PROP Default_Filter ""
+# Begin Source File
+
+SOURCE=.\Array.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\Array.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\def.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\DynArray.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\DynArray.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\FFTReal.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\FFTReal.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\FFTRealFixLen.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\FFTRealFixLen.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\FFTRealFixLenParam.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\FFTRealPassDirect.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\FFTRealPassDirect.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\FFTRealPassInverse.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\FFTRealPassInverse.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\FFTRealSelect.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\FFTRealSelect.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\FFTRealUseTrigo.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\FFTRealUseTrigo.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\OscSinCos.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\OscSinCos.hpp
+# End Source File
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+# Begin Group "Test"
+
+# PROP Default_Filter ""
+# Begin Group "stopwatch"
+
+# PROP Default_Filter ""
+# Begin Source File
+
+SOURCE=.\stopwatch\ClockCycleCounter.cpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\stopwatch\ClockCycleCounter.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\stopwatch\ClockCycleCounter.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\stopwatch\def.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\stopwatch\fnc.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\stopwatch\fnc.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\stopwatch\Int64.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\stopwatch\StopWatch.cpp
+# End Source File
+# Begin Source File
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+SOURCE=.\stopwatch\StopWatch.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\stopwatch\StopWatch.hpp
+# End Source File
+# End Group
+# Begin Source File
+
+SOURCE=.\test.cpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\test_fnc.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\test_fnc.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\test_settings.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\TestAccuracy.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\TestAccuracy.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\TestHelperFixLen.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\TestHelperFixLen.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\TestHelperNormal.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\TestHelperNormal.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\TestSpeed.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\TestSpeed.hpp
+# End Source File
+# Begin Source File
+
+SOURCE=.\TestWhiteNoiseGen.h
+# End Source File
+# Begin Source File
+
+SOURCE=.\TestWhiteNoiseGen.hpp
+# End Source File
+# End Group
+# End Target
+# End Project
diff --git a/demos/spectrum/fftreal/FFTReal.dsw b/demos/spectrum/fftreal/FFTReal.dsw
new file mode 100644
index 0000000..076b0ae
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTReal.dsw
@@ -0,0 +1,29 @@
+Microsoft Developer Studio Workspace File, Format Version 6.00
+# WARNING: DO NOT EDIT OR DELETE THIS WORKSPACE FILE!
+
+###############################################################################
+
+Project: "FFTReal"=.\FFTReal.dsp - Package Owner=<4>
+
+Package=<5>
+{{{
+}}}
+
+Package=<4>
+{{{
+}}}
+
+###############################################################################
+
+Global:
+
+Package=<5>
+{{{
+}}}
+
+Package=<3>
+{{{
+}}}
+
+###############################################################################
+
diff --git a/demos/spectrum/fftreal/FFTReal.h b/demos/spectrum/fftreal/FFTReal.h
new file mode 100644
index 0000000..9fb2725
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTReal.h
@@ -0,0 +1,142 @@
+/*****************************************************************************
+
+        FFTReal.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (FFTReal_HEADER_INCLUDED)
+#define	FFTReal_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"def.h"
+#include	"DynArray.h"
+#include	"OscSinCos.h"
+
+
+
+template <class DT>
+class FFTReal
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+	enum {			MAX_BIT_DEPTH	= 30	};	// So length can be represented as long int
+
+	typedef	DT	DataType;
+
+	explicit			FFTReal (long length);
+	virtual			~FFTReal () {}
+
+	long				get_length () const;
+	void				do_fft (DataType f [], const DataType x []) const;
+	void				do_ifft (const DataType f [], DataType x []) const;
+	void				rescale (DataType x []) const;
+	DataType *		use_buffer () const;
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+   // Over this bit depth, we use direct calculation for sin/cos
+   enum {	      TRIGO_BD_LIMIT	= 12  };
+
+	typedef	OscSinCos <DataType>	OscType;
+
+	void				init_br_lut ();
+	void				init_trigo_lut ();
+	void				init_trigo_osc ();
+
+	FORCEINLINE const long *
+						get_br_ptr () const;
+	FORCEINLINE const DataType	*
+						get_trigo_ptr (int level) const;
+	FORCEINLINE long
+						get_trigo_level_index (int level) const;
+
+	inline void		compute_fft_general (DataType f [], const DataType x []) const;
+	inline void		compute_direct_pass_1_2 (DataType df [], const DataType x []) const;
+	inline void		compute_direct_pass_3 (DataType df [], const DataType sf []) const;
+	inline void		compute_direct_pass_n (DataType df [], const DataType sf [], int pass) const;
+	inline void		compute_direct_pass_n_lut (DataType df [], const DataType sf [], int pass) const;
+	inline void		compute_direct_pass_n_osc (DataType df [], const DataType sf [], int pass) const;
+
+	inline void		compute_ifft_general (const DataType f [], DataType x []) const;
+	inline void		compute_inverse_pass_n (DataType df [], const DataType sf [], int pass) const;
+	inline void		compute_inverse_pass_n_osc (DataType df [], const DataType sf [], int pass) const;
+	inline void		compute_inverse_pass_n_lut (DataType df [], const DataType sf [], int pass) const;
+	inline void		compute_inverse_pass_3 (DataType df [], const DataType sf []) const;
+	inline void		compute_inverse_pass_1_2 (DataType x [], const DataType sf []) const;
+
+	const long		_length;
+	const int		_nbr_bits;
+	DynArray <long>
+						_br_lut;
+	DynArray <DataType>
+						_trigo_lut;
+	mutable DynArray <DataType>
+						_buffer;
+   mutable DynArray <OscType>
+						_trigo_osc;
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						FFTReal ();
+						FFTReal (const FFTReal &other);
+	FFTReal &		operator = (const FFTReal &other);
+	bool				operator == (const FFTReal &other);
+	bool				operator != (const FFTReal &other);
+
+};	// class FFTReal
+
+
+
+#include	"FFTReal.hpp"
+
+
+
+#endif	// FFTReal_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/FFTReal.hpp b/demos/spectrum/fftreal/FFTReal.hpp
new file mode 100644
index 0000000..335d771
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTReal.hpp
@@ -0,0 +1,916 @@
+/*****************************************************************************
+
+        FFTReal.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (FFTReal_CURRENT_CODEHEADER)
+	#error Recursive inclusion of FFTReal code header.
+#endif
+#define	FFTReal_CURRENT_CODEHEADER
+
+#if ! defined (FFTReal_CODEHEADER_INCLUDED)
+#define	FFTReal_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	<cassert>
+#include	<cmath>
+
+
+
+static inline bool	FFTReal_is_pow2 (long x)
+{
+	assert (x > 0);
+
+	return  ((x & -x) == x);
+}
+
+
+
+static inline int	FFTReal_get_next_pow2 (long x)
+{
+	--x;
+
+	int				p = 0;
+	while ((x & ~0xFFFFL) != 0)
+	{
+		p += 16;
+		x >>= 16;
+	}
+	while ((x & ~0xFL) != 0)
+	{
+		p += 4;
+		x >>= 4;
+	}
+	while (x > 0)
+	{
+		++p;
+		x >>= 1;
+	}
+
+	return (p);
+}
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*
+==============================================================================
+Name: ctor
+Input parameters:
+	- length: length of the array on which we want to do a FFT. Range: power of
+		2 only, > 0.
+Throws: std::bad_alloc
+==============================================================================
+*/
+
+template <class DT>
+FFTReal <DT>::FFTReal (long length)
+:	_length (length)
+,	_nbr_bits (FFTReal_get_next_pow2 (length))
+,	_br_lut ()
+,	_trigo_lut ()
+,	_buffer (length)
+,	_trigo_osc ()
+{
+	assert (FFTReal_is_pow2 (length));
+	assert (_nbr_bits <= MAX_BIT_DEPTH);
+
+	init_br_lut ();
+	init_trigo_lut ();
+	init_trigo_osc ();
+}
+
+
+
+/*
+==============================================================================
+Name: get_length
+Description:
+	Returns the number of points processed by this FFT object.
+Returns: The number of points, power of 2, > 0.
+Throws: Nothing
+==============================================================================
+*/
+
+template <class DT>
+long	FFTReal <DT>::get_length () const
+{
+	return (_length);
+}
+
+
+
+/*
+==============================================================================
+Name: do_fft
+Description:
+	Compute the FFT of the array.
+Input parameters:
+	- x: pointer on the source array (time).
+Output parameters:
+	- f: pointer on the destination array (frequencies).
+		f [0...length(x)/2] = real values,
+		f [length(x)/2+1...length(x)-1] = negative imaginary values of
+		coefficents 1...length(x)/2-1.
+Throws: Nothing
+==============================================================================
+*/
+
+template <class DT>
+void	FFTReal <DT>::do_fft (DataType f [], const DataType x []) const
+{
+	assert (f != 0);
+	assert (f != use_buffer ());
+	assert (x != 0);
+	assert (x != use_buffer ());
+	assert (x != f);
+
+	// General case
+	if (_nbr_bits > 2)
+	{
+		compute_fft_general (f, x);
+	}
+
+	// 4-point FFT
+	else if (_nbr_bits == 2)
+	{
+		f [1] = x [0] - x [2];
+		f [3] = x [1] - x [3];
+
+		const DataType	b_0 = x [0] + x [2];
+		const DataType	b_2 = x [1] + x [3];
+		
+		f [0] = b_0 + b_2;
+		f [2] = b_0 - b_2;
+	}
+
+	// 2-point FFT
+	else if (_nbr_bits == 1)
+	{
+		f [0] = x [0] + x [1];
+		f [1] = x [0] - x [1];
+	}
+
+	// 1-point FFT
+	else
+	{
+		f [0] = x [0];
+	}
+}
+
+
+
+/*
+==============================================================================
+Name: do_ifft
+Description:
+	Compute the inverse FFT of the array. Note that data must be post-scaled:
+	IFFT (FFT (x)) = x * length (x).
+Input parameters:
+	- f: pointer on the source array (frequencies).
+		f [0...length(x)/2] = real values
+		f [length(x)/2+1...length(x)-1] = negative imaginary values of
+		coefficents 1...length(x)/2-1.
+Output parameters:
+	- x: pointer on the destination array (time).
+Throws: Nothing
+==============================================================================
+*/
+
+template <class DT>
+void	FFTReal <DT>::do_ifft (const DataType f [], DataType x []) const
+{
+	assert (f != 0);
+	assert (f != use_buffer ());
+	assert (x != 0);
+	assert (x != use_buffer ());
+	assert (x != f);
+
+	// General case
+	if (_nbr_bits > 2)
+	{
+		compute_ifft_general (f, x);
+	}
+
+	// 4-point IFFT
+	else if (_nbr_bits == 2)
+	{
+		const DataType	b_0 = f [0] + f [2];
+		const DataType	b_2 = f [0] - f [2];
+
+		x [0] = b_0 + f [1] * 2;
+		x [2] = b_0 - f [1] * 2;
+		x [1] = b_2 + f [3] * 2;
+		x [3] = b_2 - f [3] * 2;
+	}
+
+	// 2-point IFFT
+	else if (_nbr_bits == 1)
+	{
+		x [0] = f [0] + f [1];
+		x [1] = f [0] - f [1];
+	}
+
+	// 1-point IFFT
+	else
+	{
+		x [0] = f [0];
+	}
+}
+
+
+
+/*
+==============================================================================
+Name: rescale
+Description:
+	Scale an array by divide each element by its length. This function should
+	be called after FFT + IFFT.
+Input parameters:
+	- x: pointer on array to rescale (time or frequency).
+Throws: Nothing
+==============================================================================
+*/
+
+template <class DT>
+void	FFTReal <DT>::rescale (DataType x []) const
+{
+	const DataType	mul = DataType (1.0 / _length);
+
+	if (_length < 4)
+	{
+		long				i = _length - 1;
+		do
+		{
+			x [i] *= mul;
+			--i;
+		}
+		while (i >= 0);
+	}
+
+	else
+	{
+		assert ((_length & 3) == 0);
+
+		// Could be optimized with SIMD instruction sets (needs alignment check)
+		long				i = _length - 4;
+		do
+		{
+			x [i + 0] *= mul;
+			x [i + 1] *= mul;
+			x [i + 2] *= mul;
+			x [i + 3] *= mul;
+			i -= 4;
+		}
+		while (i >= 0);
+	}
+}
+
+
+
+/*
+==============================================================================
+Name: use_buffer
+Description:
+	Access the internal buffer, whose length is the FFT one.
+	Buffer content will be erased at each do_fft() / do_ifft() call!
+	This buffer cannot be used as:
+		- source for FFT or IFFT done with this object
+		- destination for FFT or IFFT done with this object
+Returns:
+	Buffer start address
+Throws: Nothing
+==============================================================================
+*/
+
+template <class DT>
+typename FFTReal <DT>::DataType *	FFTReal <DT>::use_buffer () const
+{
+	return (&_buffer [0]);
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class DT>
+void	FFTReal <DT>::init_br_lut ()
+{
+	const long		length = 1L << _nbr_bits;
+	_br_lut.resize (length);
+
+	_br_lut [0] = 0;
+	long				br_index = 0;
+	for (long cnt = 1; cnt < length; ++cnt)
+	{
+		// ++br_index (bit reversed)
+		long				bit = length >> 1;
+		while (((br_index ^= bit) & bit) == 0)
+		{
+			bit >>= 1;
+		}
+
+		_br_lut [cnt] = br_index;
+	}
+}
+
+
+
+template <class DT>
+void	FFTReal <DT>::init_trigo_lut ()
+{
+	using namespace std;
+
+	if (_nbr_bits > 3)
+	{
+		const long		total_len = (1L << (_nbr_bits - 1)) - 4;
+		_trigo_lut.resize (total_len);
+
+		for (int level = 3; level < _nbr_bits; ++level)
+		{
+			const long		level_len = 1L << (level - 1);
+			DataType	* const	level_ptr =
+				&_trigo_lut [get_trigo_level_index (level)];
+			const double	mul = PI / (level_len << 1);
+
+			for (long i = 0; i < level_len; ++ i)
+			{
+				level_ptr [i] = static_cast <DataType> (cos (i * mul));
+			}
+		}
+	}
+}
+
+
+
+template <class DT>
+void	FFTReal <DT>::init_trigo_osc ()
+{
+	const int		nbr_osc = _nbr_bits - TRIGO_BD_LIMIT;
+	if (nbr_osc > 0)
+	{
+		_trigo_osc.resize (nbr_osc);
+
+		for (int osc_cnt = 0; osc_cnt < nbr_osc; ++osc_cnt)
+		{
+			OscType &		osc = _trigo_osc [osc_cnt];
+
+			const long		len = 1L << (TRIGO_BD_LIMIT + osc_cnt);
+			const double	mul = (0.5 * PI) / len;
+			osc.set_step (mul);
+		}
+	}
+}
+
+
+
+template <class DT>
+const long *	FFTReal <DT>::get_br_ptr () const
+{
+	return (&_br_lut [0]);
+}
+
+
+
+template <class DT>
+const typename FFTReal <DT>::DataType *	FFTReal <DT>::get_trigo_ptr (int level) const
+{
+	assert (level >= 3);
+
+	return (&_trigo_lut [get_trigo_level_index (level)]);
+}
+
+
+
+template <class DT>
+long	FFTReal <DT>::get_trigo_level_index (int level) const
+{
+	assert (level >= 3);
+
+	return ((1L << (level - 1)) - 4);
+}
+
+
+
+// Transform in several passes
+template <class DT>
+void	FFTReal <DT>::compute_fft_general (DataType f [], const DataType x []) const
+{
+	assert (f != 0);
+	assert (f != use_buffer ());
+	assert (x != 0);
+	assert (x != use_buffer ());
+	assert (x != f);
+
+	DataType *		sf;
+	DataType *		df;
+
+	if ((_nbr_bits & 1) != 0)
+	{
+		df = use_buffer ();
+		sf = f;
+	}
+	else
+	{
+		df = f;
+		sf = use_buffer ();
+	}
+
+	compute_direct_pass_1_2 (df, x);
+	compute_direct_pass_3 (sf, df);
+
+	for (int pass = 3; pass < _nbr_bits; ++ pass)
+	{
+		compute_direct_pass_n (df, sf, pass);
+
+		DataType * const	temp_ptr = df;
+		df = sf;
+		sf = temp_ptr;
+	}
+}
+
+
+
+template <class DT>
+void	FFTReal <DT>::compute_direct_pass_1_2 (DataType df [], const DataType x []) const
+{
+	assert (df != 0);
+	assert (x != 0);
+	assert (df != x);
+
+	const long * const	bit_rev_lut_ptr = get_br_ptr ();
+	long				coef_index = 0;
+	do
+	{
+		const long		rev_index_0 = bit_rev_lut_ptr [coef_index];
+		const long		rev_index_1 = bit_rev_lut_ptr [coef_index + 1];
+		const long		rev_index_2 = bit_rev_lut_ptr [coef_index + 2];
+		const long		rev_index_3 = bit_rev_lut_ptr [coef_index + 3];
+
+		DataType	* const	df2 = df + coef_index;
+		df2 [1] = x [rev_index_0] - x [rev_index_1];
+		df2 [3] = x [rev_index_2] - x [rev_index_3];
+
+		const DataType	sf_0 = x [rev_index_0] + x [rev_index_1];
+		const DataType	sf_2 = x [rev_index_2] + x [rev_index_3];
+
+		df2 [0] = sf_0 + sf_2;
+		df2 [2] = sf_0 - sf_2;
+		
+		coef_index += 4;
+	}
+	while (coef_index < _length);
+}
+
+
+
+template <class DT>
+void	FFTReal <DT>::compute_direct_pass_3 (DataType df [], const DataType sf []) const
+{
+	assert (df != 0);
+	assert (sf != 0);
+	assert (df != sf);
+
+	const DataType	sqrt2_2 = DataType (SQRT2 * 0.5);
+	long				coef_index = 0;
+	do
+	{
+		DataType			v;
+
+		df [coef_index] = sf [coef_index] + sf [coef_index + 4];
+		df [coef_index + 4] = sf [coef_index] - sf [coef_index + 4];
+		df [coef_index + 2] = sf [coef_index + 2];
+		df [coef_index + 6] = sf [coef_index + 6];
+
+		v = (sf [coef_index + 5] - sf [coef_index + 7]) * sqrt2_2;
+		df [coef_index + 1] = sf [coef_index + 1] + v;
+		df [coef_index + 3] = sf [coef_index + 1] - v;
+
+		v = (sf [coef_index + 5] + sf [coef_index + 7]) * sqrt2_2;
+		df [coef_index + 5] = v + sf [coef_index + 3];
+		df [coef_index + 7] = v - sf [coef_index + 3];
+
+		coef_index += 8;
+	}
+	while (coef_index < _length);
+}
+
+
+
+template <class DT>
+void	FFTReal <DT>::compute_direct_pass_n (DataType df [], const DataType sf [], int pass) const
+{
+	assert (df != 0);
+	assert (sf != 0);
+	assert (df != sf);
+	assert (pass >= 3);
+	assert (pass < _nbr_bits);
+
+	if (pass <= TRIGO_BD_LIMIT)
+	{
+		compute_direct_pass_n_lut (df, sf, pass);
+	}
+	else
+	{
+		compute_direct_pass_n_osc (df, sf, pass);
+	}
+}
+
+
+
+template <class DT>
+void	FFTReal <DT>::compute_direct_pass_n_lut (DataType df [], const DataType sf [], int pass) const
+{
+	assert (df != 0);
+	assert (sf != 0);
+	assert (df != sf);
+	assert (pass >= 3);
+	assert (pass < _nbr_bits);
+
+	const long		nbr_coef = 1 << pass;
+	const long		h_nbr_coef = nbr_coef >> 1;
+	const long		d_nbr_coef = nbr_coef << 1;
+	long				coef_index = 0;
+	const DataType	* const	cos_ptr = get_trigo_ptr (pass);
+	do
+	{
+		const DataType	* const	sf1r = sf + coef_index;
+		const DataType	* const	sf2r = sf1r + nbr_coef;
+		DataType			* const	dfr = df + coef_index;
+		DataType			* const	dfi = dfr + nbr_coef;
+
+		// Extreme coefficients are always real
+		dfr [0] = sf1r [0] + sf2r [0];
+		dfi [0] = sf1r [0] - sf2r [0];	// dfr [nbr_coef] =
+		dfr [h_nbr_coef] = sf1r [h_nbr_coef];
+		dfi [h_nbr_coef] = sf2r [h_nbr_coef];
+
+		// Others are conjugate complex numbers
+		const DataType * const	sf1i = sf1r + h_nbr_coef;
+		const DataType * const	sf2i = sf1i + nbr_coef;
+		for (long i = 1; i < h_nbr_coef; ++ i)
+		{
+			const DataType	c = cos_ptr [i];					// cos (i*PI/nbr_coef);
+			const DataType	s = cos_ptr [h_nbr_coef - i];	// sin (i*PI/nbr_coef);
+			DataType	 		v;
+
+			v = sf2r [i] * c - sf2i [i] * s;
+			dfr [i] = sf1r [i] + v;
+			dfi [-i] = sf1r [i] - v;	// dfr [nbr_coef - i] =
+
+			v = sf2r [i] * s + sf2i [i] * c;
+			dfi [i] = v + sf1i [i];
+			dfi [nbr_coef - i] = v - sf1i [i];
+		}
+
+		coef_index += d_nbr_coef;
+	}
+	while (coef_index < _length);
+}
+
+
+
+template <class DT>
+void	FFTReal <DT>::compute_direct_pass_n_osc (DataType df [], const DataType sf [], int pass) const
+{
+	assert (df != 0);
+	assert (sf != 0);
+	assert (df != sf);
+	assert (pass > TRIGO_BD_LIMIT);
+	assert (pass < _nbr_bits);
+
+	const long		nbr_coef = 1 << pass;
+	const long		h_nbr_coef = nbr_coef >> 1;
+	const long		d_nbr_coef = nbr_coef << 1;
+	long				coef_index = 0;
+	OscType &		osc = _trigo_osc [pass - (TRIGO_BD_LIMIT + 1)];
+	do
+	{
+		const DataType	* const	sf1r = sf + coef_index;
+		const DataType	* const	sf2r = sf1r + nbr_coef;
+		DataType			* const	dfr = df + coef_index;
+		DataType			* const	dfi = dfr + nbr_coef;
+
+		osc.clear_buffers ();
+
+		// Extreme coefficients are always real
+		dfr [0] = sf1r [0] + sf2r [0];
+		dfi [0] = sf1r [0] - sf2r [0];	// dfr [nbr_coef] =
+		dfr [h_nbr_coef] = sf1r [h_nbr_coef];
+		dfi [h_nbr_coef] = sf2r [h_nbr_coef];
+
+		// Others are conjugate complex numbers
+		const DataType * const	sf1i = sf1r + h_nbr_coef;
+		const DataType * const	sf2i = sf1i + nbr_coef;
+		for (long i = 1; i < h_nbr_coef; ++ i)
+		{
+			osc.step ();
+			const DataType	c = osc.get_cos ();
+			const DataType	s = osc.get_sin ();
+			DataType	 		v;
+
+			v = sf2r [i] * c - sf2i [i] * s;
+			dfr [i] = sf1r [i] + v;
+			dfi [-i] = sf1r [i] - v;	// dfr [nbr_coef - i] =
+
+			v = sf2r [i] * s + sf2i [i] * c;
+			dfi [i] = v + sf1i [i];
+			dfi [nbr_coef - i] = v - sf1i [i];
+		}
+
+		coef_index += d_nbr_coef;
+	}
+	while (coef_index < _length);
+}
+
+
+
+// Transform in several pass
+template <class DT>
+void	FFTReal <DT>::compute_ifft_general (const DataType f [], DataType x []) const
+{
+	assert (f != 0);
+	assert (f != use_buffer ());
+	assert (x != 0);
+	assert (x != use_buffer ());
+	assert (x != f);
+
+	DataType *		sf = const_cast <DataType *> (f);
+	DataType *		df;
+	DataType *		df_temp;
+
+	if (_nbr_bits & 1)
+	{
+		df = use_buffer ();
+		df_temp = x;
+	}
+	else
+	{
+		df = x;
+		df_temp = use_buffer ();
+	}
+
+	for (int pass = _nbr_bits - 1; pass >= 3; -- pass)
+	{
+		compute_inverse_pass_n (df, sf, pass);
+
+		if (pass < _nbr_bits - 1)
+		{
+			DataType	* const	temp_ptr = df;
+			df = sf;
+			sf = temp_ptr;
+		}
+		else
+		{
+			sf = df;
+			df = df_temp;
+		}
+	}
+
+	compute_inverse_pass_3 (df, sf);
+	compute_inverse_pass_1_2 (x, df);
+}
+
+
+
+template <class DT>
+void	FFTReal <DT>::compute_inverse_pass_n (DataType df [], const DataType sf [], int pass) const
+{
+	assert (df != 0);
+	assert (sf != 0);
+	assert (df != sf);
+	assert (pass >= 3);
+	assert (pass < _nbr_bits);
+
+	if (pass <= TRIGO_BD_LIMIT)
+	{
+		compute_inverse_pass_n_lut (df, sf, pass);
+	}
+	else
+	{
+		compute_inverse_pass_n_osc (df, sf, pass);
+	}
+}
+
+
+
+template <class DT>
+void	FFTReal <DT>::compute_inverse_pass_n_lut (DataType df [], const DataType sf [], int pass) const
+{
+	assert (df != 0);
+	assert (sf != 0);
+	assert (df != sf);
+	assert (pass >= 3);
+	assert (pass < _nbr_bits);
+
+	const long		nbr_coef = 1 << pass;
+	const long		h_nbr_coef = nbr_coef >> 1;
+	const long		d_nbr_coef = nbr_coef << 1;
+	long				coef_index = 0;
+	const DataType * const	cos_ptr = get_trigo_ptr (pass);
+	do
+	{
+		const DataType	* const	sfr = sf + coef_index;
+		const DataType	* const	sfi = sfr + nbr_coef;
+		DataType			* const	df1r = df + coef_index;
+		DataType			* const	df2r = df1r + nbr_coef;
+
+		// Extreme coefficients are always real
+		df1r [0] = sfr [0] + sfi [0];		// + sfr [nbr_coef]
+		df2r [0] = sfr [0] - sfi [0];		// - sfr [nbr_coef]
+		df1r [h_nbr_coef] = sfr [h_nbr_coef] * 2;
+		df2r [h_nbr_coef] = sfi [h_nbr_coef] * 2;
+
+		// Others are conjugate complex numbers
+		DataType * const	df1i = df1r + h_nbr_coef;
+		DataType * const	df2i = df1i + nbr_coef;
+		for (long i = 1; i < h_nbr_coef; ++ i)
+		{
+			df1r [i] = sfr [i] + sfi [-i];		// + sfr [nbr_coef - i]
+			df1i [i] = sfi [i] - sfi [nbr_coef - i];
+
+			const DataType	c = cos_ptr [i];					// cos (i*PI/nbr_coef);
+			const DataType	s = cos_ptr [h_nbr_coef - i];	// sin (i*PI/nbr_coef);
+			const DataType	vr = sfr [i] - sfi [-i];		// - sfr [nbr_coef - i]
+			const DataType	vi = sfi [i] + sfi [nbr_coef - i];
+
+			df2r [i] = vr * c + vi * s;
+			df2i [i] = vi * c - vr * s;
+		}
+
+		coef_index += d_nbr_coef;
+	}
+	while (coef_index < _length);
+}
+
+
+
+template <class DT>
+void	FFTReal <DT>::compute_inverse_pass_n_osc (DataType df [], const DataType sf [], int pass) const
+{
+	assert (df != 0);
+	assert (sf != 0);
+	assert (df != sf);
+	assert (pass > TRIGO_BD_LIMIT);
+	assert (pass < _nbr_bits);
+
+	const long		nbr_coef = 1 << pass;
+	const long		h_nbr_coef = nbr_coef >> 1;
+	const long		d_nbr_coef = nbr_coef << 1;
+	long				coef_index = 0;
+	OscType &		osc = _trigo_osc [pass - (TRIGO_BD_LIMIT + 1)];
+	do
+	{
+		const DataType	* const	sfr = sf + coef_index;
+		const DataType	* const	sfi = sfr + nbr_coef;
+		DataType			* const	df1r = df + coef_index;
+		DataType			* const	df2r = df1r + nbr_coef;
+
+		osc.clear_buffers ();
+
+		// Extreme coefficients are always real
+		df1r [0] = sfr [0] + sfi [0];		// + sfr [nbr_coef]
+		df2r [0] = sfr [0] - sfi [0];		// - sfr [nbr_coef]
+		df1r [h_nbr_coef] = sfr [h_nbr_coef] * 2;
+		df2r [h_nbr_coef] = sfi [h_nbr_coef] * 2;
+
+		// Others are conjugate complex numbers
+		DataType * const	df1i = df1r + h_nbr_coef;
+		DataType * const	df2i = df1i + nbr_coef;
+		for (long i = 1; i < h_nbr_coef; ++ i)
+		{
+			df1r [i] = sfr [i] + sfi [-i];		// + sfr [nbr_coef - i]
+			df1i [i] = sfi [i] - sfi [nbr_coef - i];
+
+			osc.step ();
+			const DataType	c = osc.get_cos ();
+			const DataType	s = osc.get_sin ();
+			const DataType	vr = sfr [i] - sfi [-i];		// - sfr [nbr_coef - i]
+			const DataType	vi = sfi [i] + sfi [nbr_coef - i];
+
+			df2r [i] = vr * c + vi * s;
+			df2i [i] = vi * c - vr * s;
+		}
+
+		coef_index += d_nbr_coef;
+	}
+	while (coef_index < _length);
+}
+
+
+
+template <class DT>
+void	FFTReal <DT>::compute_inverse_pass_3 (DataType df [], const DataType sf []) const
+{
+	assert (df != 0);
+	assert (sf != 0);
+	assert (df != sf);
+
+	const DataType	sqrt2_2 = DataType (SQRT2 * 0.5);
+	long				coef_index = 0;
+	do
+	{
+		df [coef_index] = sf [coef_index] + sf [coef_index + 4];
+		df [coef_index + 4] = sf [coef_index] - sf [coef_index + 4];
+		df [coef_index + 2] = sf [coef_index + 2] * 2;
+		df [coef_index + 6] = sf [coef_index + 6] * 2;
+
+		df [coef_index + 1] = sf [coef_index + 1] + sf [coef_index + 3];
+		df [coef_index + 3] = sf [coef_index + 5] - sf [coef_index + 7];
+
+		const DataType	vr = sf [coef_index + 1] - sf [coef_index + 3];
+		const DataType	vi = sf [coef_index + 5] + sf [coef_index + 7];
+
+		df [coef_index + 5] = (vr + vi) * sqrt2_2;
+		df [coef_index + 7] = (vi - vr) * sqrt2_2;
+
+		coef_index += 8;
+	}
+	while (coef_index < _length);
+}
+
+
+
+template <class DT>
+void	FFTReal <DT>::compute_inverse_pass_1_2 (DataType x [], const DataType sf []) const
+{
+	assert (x != 0);
+	assert (sf != 0);
+	assert (x != sf);
+
+	const long *	bit_rev_lut_ptr = get_br_ptr ();
+	const DataType *	sf2 = sf;
+	long				coef_index = 0;
+	do
+	{
+		{
+			const DataType	b_0 = sf2 [0] + sf2 [2];
+			const DataType	b_2 = sf2 [0] - sf2 [2];
+			const DataType	b_1 = sf2 [1] * 2;
+			const DataType	b_3 = sf2 [3] * 2;
+
+			x [bit_rev_lut_ptr [0]] = b_0 + b_1;
+			x [bit_rev_lut_ptr [1]] = b_0 - b_1;
+			x [bit_rev_lut_ptr [2]] = b_2 + b_3;
+			x [bit_rev_lut_ptr [3]] = b_2 - b_3;
+		}
+		{
+			const DataType	b_0 = sf2 [4] + sf2 [6];
+			const DataType	b_2 = sf2 [4] - sf2 [6];
+			const DataType	b_1 = sf2 [5] * 2;
+			const DataType	b_3 = sf2 [7] * 2;
+
+			x [bit_rev_lut_ptr [4]] = b_0 + b_1;
+			x [bit_rev_lut_ptr [5]] = b_0 - b_1;
+			x [bit_rev_lut_ptr [6]] = b_2 + b_3;
+			x [bit_rev_lut_ptr [7]] = b_2 - b_3;
+		}
+
+		sf2 += 8;
+		coef_index += 8;
+		bit_rev_lut_ptr += 8;
+	}
+	while (coef_index < _length);
+}
+
+
+
+#endif	// FFTReal_CODEHEADER_INCLUDED
+
+#undef FFTReal_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/FFTRealFixLen.h b/demos/spectrum/fftreal/FFTRealFixLen.h
new file mode 100644
index 0000000..0b80266
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTRealFixLen.h
@@ -0,0 +1,130 @@
+/*****************************************************************************
+
+        FFTRealFixLen.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (FFTRealFixLen_HEADER_INCLUDED)
+#define	FFTRealFixLen_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"Array.h"
+#include	"DynArray.h"
+#include	"FFTRealFixLenParam.h"
+#include	"OscSinCos.h"
+
+
+
+template <int LL2>
+class FFTRealFixLen
+{
+	typedef	int	CompileTimeCheck1 [(LL2 >=  0) ? 1 : -1];
+	typedef	int	CompileTimeCheck2 [(LL2 <= 30) ? 1 : -1];
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+   typedef	FFTRealFixLenParam::DataType   DataType;
+	typedef	OscSinCos <DataType>	OscType;
+
+	enum {			FFT_LEN_L2	= LL2	};
+	enum {			FFT_LEN		= 1 << FFT_LEN_L2	};
+
+						FFTRealFixLen ();
+
+	inline long		get_length () const;
+	void				do_fft (DataType f [], const DataType x []);
+	void				do_ifft (const DataType f [], DataType x []);
+	void				rescale (DataType x []) const;
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+	enum {			TRIGO_BD_LIMIT	= FFTRealFixLenParam::TRIGO_BD_LIMIT	};
+
+	enum {			BR_ARR_SIZE_L2	= ((FFT_LEN_L2 - 3) < 0) ? 0 : (FFT_LEN_L2 - 2)	};
+	enum {			BR_ARR_SIZE		= 1 << BR_ARR_SIZE_L2	};
+
+   enum {			TRIGO_BD			=   ((FFT_LEN_L2 - TRIGO_BD_LIMIT) < 0)
+											  ? (int)FFT_LEN_L2
+											  : (int)TRIGO_BD_LIMIT };
+	enum {			TRIGO_TABLE_ARR_SIZE_L2	= (LL2 < 4) ? 0 : (TRIGO_BD - 2)	};
+	enum {			TRIGO_TABLE_ARR_SIZE	= 1 << TRIGO_TABLE_ARR_SIZE_L2	};
+
+	enum {			NBR_TRIGO_OSC			= FFT_LEN_L2 - TRIGO_BD	};
+	enum {			TRIGO_OSC_ARR_SIZE	=	(NBR_TRIGO_OSC > 0) ? NBR_TRIGO_OSC : 1	};
+
+	void				build_br_lut ();
+	void				build_trigo_lut ();
+	void				build_trigo_osc ();
+
+	DynArray <DataType>
+						_buffer;
+	DynArray <long>
+						_br_data;
+	DynArray <DataType>
+						_trigo_data;
+   Array <OscType, TRIGO_OSC_ARR_SIZE>
+						_trigo_osc;
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						FFTRealFixLen (const FFTRealFixLen &other);
+	FFTRealFixLen&	operator = (const FFTRealFixLen &other);
+	bool				operator == (const FFTRealFixLen &other);
+	bool				operator != (const FFTRealFixLen &other);
+
+};	// class FFTRealFixLen
+
+
+
+#include	"FFTRealFixLen.hpp"
+
+
+
+#endif	// FFTRealFixLen_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/FFTRealFixLen.hpp b/demos/spectrum/fftreal/FFTRealFixLen.hpp
new file mode 100644
index 0000000..6defb00
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTRealFixLen.hpp
@@ -0,0 +1,322 @@
+/*****************************************************************************
+
+        FFTRealFixLen.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (FFTRealFixLen_CURRENT_CODEHEADER)
+	#error Recursive inclusion of FFTRealFixLen code header.
+#endif
+#define	FFTRealFixLen_CURRENT_CODEHEADER
+
+#if ! defined (FFTRealFixLen_CODEHEADER_INCLUDED)
+#define	FFTRealFixLen_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"def.h"
+#include	"FFTRealPassDirect.h"
+#include	"FFTRealPassInverse.h"
+#include	"FFTRealSelect.h"
+
+#include	<cassert>
+#include	<cmath>
+
+namespace std { }
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <int LL2>
+FFTRealFixLen <LL2>::FFTRealFixLen ()
+:	_buffer (FFT_LEN)
+,	_br_data (BR_ARR_SIZE)
+,	_trigo_data (TRIGO_TABLE_ARR_SIZE)
+,	_trigo_osc ()
+{
+	build_br_lut ();
+	build_trigo_lut ();
+	build_trigo_osc ();
+}
+
+
+
+template <int LL2>
+long	FFTRealFixLen <LL2>::get_length () const
+{
+	return (FFT_LEN);
+}
+
+
+
+// General case
+template <int LL2>
+void	FFTRealFixLen <LL2>::do_fft (DataType f [], const DataType x [])
+{
+	assert (f != 0);
+	assert (x != 0);
+	assert (x != f);
+	assert (FFT_LEN_L2 >= 3);
+
+	// Do the transform in several passes
+	const DataType	*	cos_ptr = &_trigo_data [0];
+	const long *	br_ptr = &_br_data [0];
+
+	FFTRealPassDirect <FFT_LEN_L2 - 1>::process (
+		FFT_LEN,
+		f,
+		&_buffer [0],
+		x,
+		cos_ptr,
+		TRIGO_TABLE_ARR_SIZE,
+		br_ptr,
+		&_trigo_osc [0]
+	);
+}
+
+// 4-point FFT
+template <>
+void	FFTRealFixLen <2>::do_fft (DataType f [], const DataType x [])
+{
+	assert (f != 0);
+	assert (x != 0);
+	assert (x != f);
+
+	f [1] = x [0] - x [2];
+	f [3] = x [1] - x [3];
+
+	const DataType	b_0 = x [0] + x [2];
+	const DataType	b_2 = x [1] + x [3];
+	
+	f [0] = b_0 + b_2;
+	f [2] = b_0 - b_2;
+}
+
+// 2-point FFT
+template <>
+void	FFTRealFixLen <1>::do_fft (DataType f [], const DataType x [])
+{
+	assert (f != 0);
+	assert (x != 0);
+	assert (x != f);
+
+	f [0] = x [0] + x [1];
+	f [1] = x [0] - x [1];
+}
+
+// 1-point FFT
+template <>
+void	FFTRealFixLen <0>::do_fft (DataType f [], const DataType x [])
+{
+	assert (f != 0);
+	assert (x != 0);
+
+	f [0] = x [0];
+}
+
+
+
+// General case
+template <int LL2>
+void	FFTRealFixLen <LL2>::do_ifft (const DataType f [], DataType x [])
+{
+	assert (f != 0);
+	assert (x != 0);
+	assert (x != f);
+	assert (FFT_LEN_L2 >= 3);
+
+	// Do the transform in several passes
+	DataType *		s_ptr =
+		FFTRealSelect <FFT_LEN_L2 & 1>::sel_bin (&_buffer [0], x);
+	DataType *		d_ptr =
+		FFTRealSelect <FFT_LEN_L2 & 1>::sel_bin (x, &_buffer [0]);
+	const DataType	*	cos_ptr = &_trigo_data [0];
+	const long *	br_ptr = &_br_data [0];
+
+	FFTRealPassInverse <FFT_LEN_L2 - 1>::process (
+		FFT_LEN,
+		d_ptr,
+		s_ptr,
+		f,
+		cos_ptr,
+		TRIGO_TABLE_ARR_SIZE,
+		br_ptr,
+		&_trigo_osc [0]
+	);
+}
+
+// 4-point IFFT
+template <>
+void	FFTRealFixLen <2>::do_ifft (const DataType f [], DataType x [])
+{
+	assert (f != 0);
+	assert (x != 0);
+	assert (x != f);
+
+	const DataType	b_0 = f [0] + f [2];
+	const DataType	b_2 = f [0] - f [2];
+
+	x [0] = b_0 + f [1] * 2;
+	x [2] = b_0 - f [1] * 2;
+	x [1] = b_2 + f [3] * 2;
+	x [3] = b_2 - f [3] * 2;
+}
+
+// 2-point IFFT
+template <>
+void	FFTRealFixLen <1>::do_ifft (const DataType f [], DataType x [])
+{
+	assert (f != 0);
+	assert (x != 0);
+	assert (x != f);
+
+	x [0] = f [0] + f [1];
+	x [1] = f [0] - f [1];
+}
+
+// 1-point IFFT
+template <>
+void	FFTRealFixLen <0>::do_ifft (const DataType f [], DataType x [])
+{
+	assert (f != 0);
+	assert (x != 0);
+	assert (x != f);
+
+	x [0] = f [0];
+}
+
+
+
+
+template <int LL2>
+void	FFTRealFixLen <LL2>::rescale (DataType x []) const
+{
+	assert (x != 0);
+
+	const DataType	mul = DataType (1.0 / FFT_LEN);
+
+	if (FFT_LEN < 4)
+	{
+		long				i = FFT_LEN - 1;
+		do
+		{
+			x [i] *= mul;
+			--i;
+		}
+		while (i >= 0);
+	}
+
+	else
+	{
+		assert ((FFT_LEN & 3) == 0);
+
+		// Could be optimized with SIMD instruction sets (needs alignment check)
+		long				i = FFT_LEN - 4;
+		do
+		{
+			x [i + 0] *= mul;
+			x [i + 1] *= mul;
+			x [i + 2] *= mul;
+			x [i + 3] *= mul;
+			i -= 4;
+		}
+		while (i >= 0);
+	}
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <int LL2>
+void	FFTRealFixLen <LL2>::build_br_lut ()
+{
+	_br_data [0] = 0;
+	for (long cnt = 1; cnt < BR_ARR_SIZE; ++cnt)
+	{
+		long				index = cnt << 2;
+		long				br_index = 0;
+
+		int				bit_cnt = FFT_LEN_L2;
+		do
+		{
+			br_index <<= 1;
+			br_index += (index & 1);
+			index >>= 1;
+
+			-- bit_cnt;
+		}
+		while (bit_cnt > 0);
+
+		_br_data [cnt] = br_index;
+	}
+}
+
+
+
+template <int LL2>
+void	FFTRealFixLen <LL2>::build_trigo_lut ()
+{
+	const double	mul = (0.5 * PI) / TRIGO_TABLE_ARR_SIZE;
+	for (long i = 0; i < TRIGO_TABLE_ARR_SIZE; ++ i)
+	{
+		using namespace std;
+
+		_trigo_data [i] = DataType (cos (i * mul));
+	}
+}
+
+
+
+template <int LL2>
+void	FFTRealFixLen <LL2>::build_trigo_osc ()
+{
+	for (int i = 0; i < NBR_TRIGO_OSC; ++i)
+	{
+		OscType &		osc = _trigo_osc [i];
+
+		const long		len = static_cast <long> (TRIGO_TABLE_ARR_SIZE) << (i + 1);
+		const double	mul = (0.5 * PI) / len;
+		osc.set_step (mul);
+	}
+}
+
+
+
+#endif	// FFTRealFixLen_CODEHEADER_INCLUDED
+
+#undef FFTRealFixLen_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/FFTRealFixLenParam.h b/demos/spectrum/fftreal/FFTRealFixLenParam.h
new file mode 100644
index 0000000..163c083
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTRealFixLenParam.h
@@ -0,0 +1,93 @@
+/*****************************************************************************
+
+        FFTRealFixLenParam.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (FFTRealFixLenParam_HEADER_INCLUDED)
+#define	FFTRealFixLenParam_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+class FFTRealFixLenParam
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+   // Over this bit depth, we use direct calculation for sin/cos
+   enum {	      TRIGO_BD_LIMIT	= 12  };
+
+	typedef	float	DataType;
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+#if 0	// To avoid GCC warning:
+		// All member functions in class 'FFTRealFixLenParam' are private
+						FFTRealFixLenParam ();
+						~FFTRealFixLenParam ();
+						FFTRealFixLenParam (const FFTRealFixLenParam &other);
+	FFTRealFixLenParam &
+						operator = (const FFTRealFixLenParam &other);
+	bool				operator == (const FFTRealFixLenParam &other);
+	bool				operator != (const FFTRealFixLenParam &other);
+#endif
+
+};	// class FFTRealFixLenParam
+
+
+
+//#include	"FFTRealFixLenParam.hpp"
+
+
+
+#endif	// FFTRealFixLenParam_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/FFTRealPassDirect.h b/demos/spectrum/fftreal/FFTRealPassDirect.h
new file mode 100644
index 0000000..7d19c02
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTRealPassDirect.h
@@ -0,0 +1,96 @@
+/*****************************************************************************
+
+        FFTRealPassDirect.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (FFTRealPassDirect_HEADER_INCLUDED)
+#define	FFTRealPassDirect_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"def.h"
+#include	"FFTRealFixLenParam.h"
+#include	"OscSinCos.h"
+
+
+
+template <int PASS>
+class FFTRealPassDirect
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+   typedef	FFTRealFixLenParam::DataType	DataType;
+	typedef	OscSinCos <DataType>	OscType;
+
+	FORCEINLINE static void
+						process (long len, DataType dest_ptr [], DataType src_ptr [], const DataType x_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list []);
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						FFTRealPassDirect ();
+						~FFTRealPassDirect ();
+						FFTRealPassDirect (const FFTRealPassDirect &other);
+	FFTRealPassDirect &
+						operator = (const FFTRealPassDirect &other);
+	bool				operator == (const FFTRealPassDirect &other);
+	bool				operator != (const FFTRealPassDirect &other);
+
+};	// class FFTRealPassDirect
+
+
+
+#include	"FFTRealPassDirect.hpp"
+
+
+
+#endif	// FFTRealPassDirect_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/FFTRealPassDirect.hpp b/demos/spectrum/fftreal/FFTRealPassDirect.hpp
new file mode 100644
index 0000000..db9d568
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTRealPassDirect.hpp
@@ -0,0 +1,204 @@
+/*****************************************************************************
+
+        FFTRealPassDirect.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (FFTRealPassDirect_CURRENT_CODEHEADER)
+	#error Recursive inclusion of FFTRealPassDirect code header.
+#endif
+#define	FFTRealPassDirect_CURRENT_CODEHEADER
+
+#if ! defined (FFTRealPassDirect_CODEHEADER_INCLUDED)
+#define	FFTRealPassDirect_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"FFTRealUseTrigo.h"
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <>
+void	FFTRealPassDirect <1>::process (long len, DataType dest_ptr [], DataType src_ptr [], const DataType x_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+	// First and second pass at once
+	const long		qlen = len >> 2;
+
+	long				coef_index = 0;
+	do
+	{
+		// To do: unroll the loop (2x).
+		const long		ri_0 = br_ptr [coef_index >> 2];
+		const long		ri_1 = ri_0 + 2 * qlen;	// bit_rev_lut_ptr [coef_index + 1];
+		const long		ri_2 = ri_0 + 1 * qlen;	// bit_rev_lut_ptr [coef_index + 2];
+		const long		ri_3 = ri_0 + 3 * qlen;	// bit_rev_lut_ptr [coef_index + 3];
+
+		DataType	* const	df2 = dest_ptr + coef_index;
+		df2 [1] = x_ptr [ri_0] - x_ptr [ri_1];
+		df2 [3] = x_ptr [ri_2] - x_ptr [ri_3];
+
+		const DataType	sf_0 = x_ptr [ri_0] + x_ptr [ri_1];
+		const DataType	sf_2 = x_ptr [ri_2] + x_ptr [ri_3];
+
+		df2 [0] = sf_0 + sf_2;
+		df2 [2] = sf_0 - sf_2;
+
+		coef_index += 4;
+	}
+	while (coef_index < len);
+}
+
+template <>
+void	FFTRealPassDirect <2>::process (long len, DataType dest_ptr [], DataType src_ptr [], const DataType x_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+	// Executes "previous" passes first. Inverts source and destination buffers
+	FFTRealPassDirect <1>::process (
+		len,
+		src_ptr,
+		dest_ptr,
+		x_ptr,
+		cos_ptr,
+		cos_len,
+		br_ptr,
+		osc_list
+	);
+
+	// Third pass
+	const DataType	sqrt2_2 = DataType (SQRT2 * 0.5);
+
+	long				coef_index = 0;
+	do
+	{
+		dest_ptr [coef_index    ] = src_ptr [coef_index] + src_ptr [coef_index + 4];
+		dest_ptr [coef_index + 4] = src_ptr [coef_index] - src_ptr [coef_index + 4];
+		dest_ptr [coef_index + 2] = src_ptr [coef_index + 2];
+		dest_ptr [coef_index + 6] = src_ptr [coef_index + 6];
+
+		DataType			v;
+
+		v = (src_ptr [coef_index + 5] - src_ptr [coef_index + 7]) * sqrt2_2;
+		dest_ptr [coef_index + 1] = src_ptr [coef_index + 1] + v;
+		dest_ptr [coef_index + 3] = src_ptr [coef_index + 1] - v;
+
+		v = (src_ptr [coef_index + 5] + src_ptr [coef_index + 7]) * sqrt2_2;
+		dest_ptr [coef_index + 5] = v + src_ptr [coef_index + 3];
+		dest_ptr [coef_index + 7] = v - src_ptr [coef_index + 3];
+
+		coef_index += 8;
+	}
+	while (coef_index < len);
+}
+
+template <int PASS>
+void	FFTRealPassDirect <PASS>::process (long len, DataType dest_ptr [], DataType src_ptr [], const DataType x_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+	// Executes "previous" passes first. Inverts source and destination buffers
+	FFTRealPassDirect <PASS - 1>::process (
+		len,
+		src_ptr,
+		dest_ptr,
+		x_ptr,
+		cos_ptr,
+		cos_len,
+		br_ptr,
+		osc_list
+	);
+
+	const long		dist = 1L << (PASS - 1);
+	const long		c1_r = 0;
+	const long		c1_i = dist;
+	const long		c2_r = dist * 2;
+	const long		c2_i = dist * 3;
+	const long		cend = dist * 4;
+	const long		table_step = cos_len >> (PASS - 1);
+
+   enum {	TRIGO_OSC		= PASS - FFTRealFixLenParam::TRIGO_BD_LIMIT	};
+	enum {	TRIGO_DIRECT	= (TRIGO_OSC >= 0) ? 1 : 0	};
+
+	long				coef_index = 0;
+	do
+	{
+		const DataType	* const	sf = src_ptr + coef_index;
+		DataType			* const	df = dest_ptr + coef_index;
+
+		// Extreme coefficients are always real
+		df [c1_r] = sf [c1_r] + sf [c2_r];
+		df [c2_r] = sf [c1_r] - sf [c2_r];
+		df [c1_i] = sf [c1_i];
+		df [c2_i] = sf [c2_i];
+
+		FFTRealUseTrigo <TRIGO_DIRECT>::prepare (osc_list [TRIGO_OSC]);
+
+		// Others are conjugate complex numbers
+		for (long i = 1; i < dist; ++ i)
+		{
+			DataType			c;
+			DataType			s;
+			FFTRealUseTrigo <TRIGO_DIRECT>::iterate (
+				osc_list [TRIGO_OSC],
+				c,
+				s,
+				cos_ptr,
+				i * table_step,
+				(dist - i) * table_step
+			);
+
+			const DataType	sf_r_i = sf [c1_r + i];
+			const DataType	sf_i_i = sf [c1_i + i];
+
+			const DataType	v1 = sf [c2_r + i] * c - sf [c2_i + i] * s;
+			df [c1_r + i] = sf_r_i + v1;
+			df [c2_r - i] = sf_r_i - v1;
+
+			const DataType	v2 = sf [c2_r + i] * s + sf [c2_i + i] * c;
+			df [c2_r + i] = v2 + sf_i_i;
+			df [cend - i] = v2 - sf_i_i;
+		}
+
+		coef_index += cend;
+	}
+	while (coef_index < len);
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+#endif	// FFTRealPassDirect_CODEHEADER_INCLUDED
+
+#undef FFTRealPassDirect_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/FFTRealPassInverse.h b/demos/spectrum/fftreal/FFTRealPassInverse.h
new file mode 100644
index 0000000..2de8952
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTRealPassInverse.h
@@ -0,0 +1,101 @@
+/*****************************************************************************
+
+        FFTRealPassInverse.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (FFTRealPassInverse_HEADER_INCLUDED)
+#define	FFTRealPassInverse_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"def.h"
+#include	"FFTRealFixLenParam.h"
+#include	"OscSinCos.h"
+
+
+
+
+template <int PASS>
+class FFTRealPassInverse
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+   typedef	FFTRealFixLenParam::DataType	DataType;
+	typedef	OscSinCos <DataType>	OscType;
+
+	FORCEINLINE static void
+						process (long len, DataType dest_ptr [], DataType src_ptr [], const DataType f_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list []);
+	FORCEINLINE static void
+						process_rec (long len, DataType dest_ptr [], DataType src_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list []);
+	FORCEINLINE static void
+						process_internal (long len, DataType dest_ptr [], const DataType src_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list []);
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						FFTRealPassInverse ();
+						~FFTRealPassInverse ();
+						FFTRealPassInverse (const FFTRealPassInverse &other);
+	FFTRealPassInverse &
+						operator = (const FFTRealPassInverse &other);
+	bool				operator == (const FFTRealPassInverse &other);
+	bool				operator != (const FFTRealPassInverse &other);
+
+};	// class FFTRealPassInverse
+
+
+
+#include	"FFTRealPassInverse.hpp"
+
+
+
+#endif	// FFTRealPassInverse_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/FFTRealPassInverse.hpp b/demos/spectrum/fftreal/FFTRealPassInverse.hpp
new file mode 100644
index 0000000..5737546
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTRealPassInverse.hpp
@@ -0,0 +1,229 @@
+/*****************************************************************************
+
+        FFTRealPassInverse.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (FFTRealPassInverse_CURRENT_CODEHEADER)
+	#error Recursive inclusion of FFTRealPassInverse code header.
+#endif
+#define	FFTRealPassInverse_CURRENT_CODEHEADER
+
+#if ! defined (FFTRealPassInverse_CODEHEADER_INCLUDED)
+#define	FFTRealPassInverse_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"FFTRealUseTrigo.h"
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <int PASS>
+void	FFTRealPassInverse <PASS>::process (long len, DataType dest_ptr [], DataType src_ptr [], const DataType f_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+	process_internal (
+		len,
+		dest_ptr,
+		f_ptr,
+		cos_ptr,
+		cos_len,
+		br_ptr,
+		osc_list
+	);
+	FFTRealPassInverse <PASS - 1>::process_rec (
+		len,
+		src_ptr,
+		dest_ptr,
+		cos_ptr,
+		cos_len,
+		br_ptr,
+		osc_list
+	);
+}
+
+
+
+template <int PASS>
+void	FFTRealPassInverse <PASS>::process_rec (long len, DataType dest_ptr [], DataType src_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+	process_internal (
+		len,
+		dest_ptr,
+		src_ptr,
+		cos_ptr,
+		cos_len,
+		br_ptr,
+		osc_list
+	);
+	FFTRealPassInverse <PASS - 1>::process_rec (
+		len,
+		src_ptr,
+		dest_ptr,
+		cos_ptr,
+		cos_len,
+		br_ptr,
+		osc_list
+	);
+}
+
+template <>
+void	FFTRealPassInverse <0>::process_rec (long len, DataType dest_ptr [], DataType src_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+	// Stops recursion
+}
+
+
+
+template <int PASS>
+void	FFTRealPassInverse <PASS>::process_internal (long len, DataType dest_ptr [], const DataType src_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+	const long		dist = 1L << (PASS - 1);
+	const long		c1_r = 0;
+	const long		c1_i = dist;
+	const long		c2_r = dist * 2;
+	const long		c2_i = dist * 3;
+	const long		cend = dist * 4;
+	const long		table_step = cos_len >> (PASS - 1);
+
+   enum {	TRIGO_OSC		= PASS - FFTRealFixLenParam::TRIGO_BD_LIMIT	};
+	enum {	TRIGO_DIRECT	= (TRIGO_OSC >= 0) ? 1 : 0	};
+
+	long				coef_index = 0;
+	do
+	{
+		const DataType	* const	sf = src_ptr + coef_index;
+		DataType			* const	df = dest_ptr + coef_index;
+
+		// Extreme coefficients are always real
+		df [c1_r] = sf [c1_r] + sf [c2_r];
+		df [c2_r] = sf [c1_r] - sf [c2_r];
+		df [c1_i] = sf [c1_i] * 2;
+		df [c2_i] = sf [c2_i] * 2;
+
+		FFTRealUseTrigo <TRIGO_DIRECT>::prepare (osc_list [TRIGO_OSC]);
+
+		// Others are conjugate complex numbers
+		for (long i = 1; i < dist; ++ i)
+		{
+			df [c1_r + i] = sf [c1_r + i] + sf [c2_r - i];
+			df [c1_i + i] = sf [c2_r + i] - sf [cend - i];
+
+			DataType			c;
+			DataType			s;
+			FFTRealUseTrigo <TRIGO_DIRECT>::iterate (
+				osc_list [TRIGO_OSC],
+				c,
+				s,
+				cos_ptr,
+				i * table_step,
+				(dist - i) * table_step
+			);
+
+			const DataType	vr = sf [c1_r + i] - sf [c2_r - i];
+			const DataType	vi = sf [c2_r + i] + sf [cend - i];
+
+			df [c2_r + i] = vr * c + vi * s;
+			df [c2_i + i] = vi * c - vr * s;
+		}
+
+		coef_index += cend;
+	}
+	while (coef_index < len);
+}
+
+template <>
+void	FFTRealPassInverse <2>::process_internal (long len, DataType dest_ptr [], const DataType src_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+	// Antepenultimate pass
+	const DataType	sqrt2_2 = DataType (SQRT2 * 0.5);
+
+	long				coef_index = 0;
+	do
+	{
+		dest_ptr [coef_index    ] = src_ptr [coef_index] + src_ptr [coef_index + 4];
+		dest_ptr [coef_index + 4] = src_ptr [coef_index] - src_ptr [coef_index + 4];
+		dest_ptr [coef_index + 2] = src_ptr [coef_index + 2] * 2;
+		dest_ptr [coef_index + 6] = src_ptr [coef_index + 6] * 2;
+
+		dest_ptr [coef_index + 1] = src_ptr [coef_index + 1] + src_ptr [coef_index + 3];
+		dest_ptr [coef_index + 3] = src_ptr [coef_index + 5] - src_ptr [coef_index + 7];
+
+		const DataType	vr = src_ptr [coef_index + 1] - src_ptr [coef_index + 3];
+		const DataType	vi = src_ptr [coef_index + 5] + src_ptr [coef_index + 7];
+
+		dest_ptr [coef_index + 5] = (vr + vi) * sqrt2_2;
+		dest_ptr [coef_index + 7] = (vi - vr) * sqrt2_2;
+
+		coef_index += 8;
+	}
+	while (coef_index < len);
+}
+
+template <>
+void	FFTRealPassInverse <1>::process_internal (long len, DataType dest_ptr [], const DataType src_ptr [], const DataType cos_ptr [], long cos_len, const long br_ptr [], OscType osc_list [])
+{
+	// Penultimate and last pass at once
+	const long		qlen = len >> 2;
+
+	long				coef_index = 0;
+	do
+	{
+		const long		ri_0 = br_ptr [coef_index >> 2];
+
+		const DataType	b_0 = src_ptr [coef_index    ] + src_ptr [coef_index + 2];
+		const DataType	b_2 = src_ptr [coef_index    ] - src_ptr [coef_index + 2];
+		const DataType	b_1 = src_ptr [coef_index + 1] * 2;
+		const DataType	b_3 = src_ptr [coef_index + 3] * 2;
+
+		dest_ptr [ri_0           ] = b_0 + b_1;
+		dest_ptr [ri_0 + 2 * qlen] = b_0 - b_1;
+		dest_ptr [ri_0 + 1 * qlen] = b_2 + b_3;
+		dest_ptr [ri_0 + 3 * qlen] = b_2 - b_3;
+
+		coef_index += 4;
+	}
+	while (coef_index < len);
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+#endif	// FFTRealPassInverse_CODEHEADER_INCLUDED
+
+#undef FFTRealPassInverse_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/FFTRealSelect.h b/demos/spectrum/fftreal/FFTRealSelect.h
new file mode 100644
index 0000000..bd722d4
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTRealSelect.h
@@ -0,0 +1,77 @@
+/*****************************************************************************
+
+        FFTRealSelect.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (FFTRealSelect_HEADER_INCLUDED)
+#define	FFTRealSelect_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"def.h"
+
+
+
+template <int P>
+class FFTRealSelect
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+	FORCEINLINE static float *
+						sel_bin (float *e_ptr, float *o_ptr);
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						FFTRealSelect ();
+						~FFTRealSelect ();
+						FFTRealSelect (const FFTRealSelect &other);
+	FFTRealSelect&	operator = (const FFTRealSelect &other);
+	bool				operator == (const FFTRealSelect &other);
+	bool				operator != (const FFTRealSelect &other);
+
+};	// class FFTRealSelect
+
+
+
+#include	"FFTRealSelect.hpp"
+
+
+
+#endif	// FFTRealSelect_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/FFTRealSelect.hpp b/demos/spectrum/fftreal/FFTRealSelect.hpp
new file mode 100644
index 0000000..9ddf586
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTRealSelect.hpp
@@ -0,0 +1,62 @@
+/*****************************************************************************
+
+        FFTRealSelect.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (FFTRealSelect_CURRENT_CODEHEADER)
+	#error Recursive inclusion of FFTRealSelect code header.
+#endif
+#define	FFTRealSelect_CURRENT_CODEHEADER
+
+#if ! defined (FFTRealSelect_CODEHEADER_INCLUDED)
+#define	FFTRealSelect_CODEHEADER_INCLUDED
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <int P>
+float *	FFTRealSelect <P>::sel_bin (float *e_ptr, float *o_ptr)
+{
+	return (o_ptr);
+}
+
+
+
+template <>
+float *	FFTRealSelect <0>::sel_bin (float *e_ptr, float *o_ptr)
+{
+	return (e_ptr);
+}
+
+
+
+#endif	// FFTRealSelect_CODEHEADER_INCLUDED
+
+#undef FFTRealSelect_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/FFTRealUseTrigo.h b/demos/spectrum/fftreal/FFTRealUseTrigo.h
new file mode 100644
index 0000000..c4368ee
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTRealUseTrigo.h
@@ -0,0 +1,101 @@
+/*****************************************************************************
+
+        FFTRealUseTrigo.h
+        Copyright (c) 2005 Laurent de Soras
+
+Template parameters:
+	- ALGO: algorithm choice. 0 = table, other = oscillator
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (FFTRealUseTrigo_HEADER_INCLUDED)
+#define	FFTRealUseTrigo_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"def.h"
+#include	"FFTRealFixLenParam.h"
+#include	"OscSinCos.h"
+
+
+
+template <int ALGO>
+class FFTRealUseTrigo
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+   typedef	FFTRealFixLenParam::DataType	DataType;
+	typedef	OscSinCos <DataType>	OscType;
+
+	FORCEINLINE static void
+						prepare (OscType &osc);
+	FORCEINLINE	static void
+						iterate (OscType &osc, DataType &c, DataType &s, const DataType cos_ptr [], long index_c, long index_s);
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						FFTRealUseTrigo ();
+						~FFTRealUseTrigo ();
+						FFTRealUseTrigo (const FFTRealUseTrigo &other);
+	FFTRealUseTrigo &
+						operator = (const FFTRealUseTrigo &other);
+	bool				operator == (const FFTRealUseTrigo &other);
+	bool				operator != (const FFTRealUseTrigo &other);
+
+};	// class FFTRealUseTrigo
+
+
+
+#include	"FFTRealUseTrigo.hpp"
+
+
+
+#endif	// FFTRealUseTrigo_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/FFTRealUseTrigo.hpp b/demos/spectrum/fftreal/FFTRealUseTrigo.hpp
new file mode 100644
index 0000000..aa968b8
--- /dev/null
+++ b/demos/spectrum/fftreal/FFTRealUseTrigo.hpp
@@ -0,0 +1,91 @@
+/*****************************************************************************
+
+        FFTRealUseTrigo.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (FFTRealUseTrigo_CURRENT_CODEHEADER)
+	#error Recursive inclusion of FFTRealUseTrigo code header.
+#endif
+#define	FFTRealUseTrigo_CURRENT_CODEHEADER
+
+#if ! defined (FFTRealUseTrigo_CODEHEADER_INCLUDED)
+#define	FFTRealUseTrigo_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"OscSinCos.h"
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <int ALGO>
+void	FFTRealUseTrigo <ALGO>::prepare (OscType &osc)
+{
+	osc.clear_buffers ();
+}
+
+template <>
+void	FFTRealUseTrigo <0>::prepare (OscType &osc)
+{
+	// Nothing
+}
+
+
+
+template <int ALGO>
+void	FFTRealUseTrigo <ALGO>::iterate (OscType &osc, DataType &c, DataType &s, const DataType cos_ptr [], long index_c, long index_s)
+{
+	osc.step ();
+	c = osc.get_cos ();
+	s = osc.get_sin ();
+}
+
+template <>
+void	FFTRealUseTrigo <0>::iterate (OscType &osc, DataType &c, DataType &s, const DataType cos_ptr [], long index_c, long index_s)
+{
+	c = cos_ptr [index_c];
+	s = cos_ptr [index_s];
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+#endif	// FFTRealUseTrigo_CODEHEADER_INCLUDED
+
+#undef FFTRealUseTrigo_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/OscSinCos.h b/demos/spectrum/fftreal/OscSinCos.h
new file mode 100644
index 0000000..775fc14
--- /dev/null
+++ b/demos/spectrum/fftreal/OscSinCos.h
@@ -0,0 +1,106 @@
+/*****************************************************************************
+
+        OscSinCos.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (OscSinCos_HEADER_INCLUDED)
+#define	OscSinCos_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"def.h"
+
+
+
+template <class T>
+class OscSinCos
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+	typedef	T	DataType;
+
+						OscSinCos ();
+
+	FORCEINLINE void
+						set_step (double angle_rad);
+
+	FORCEINLINE DataType
+						get_cos () const;
+	FORCEINLINE DataType
+						get_sin () const;
+	FORCEINLINE void
+						step ();
+	FORCEINLINE void
+						clear_buffers ();
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+	DataType			_pos_cos;		// Current phase expressed with sin and cos. [-1 ; 1]
+	DataType			_pos_sin;		// -
+	DataType			_step_cos;		// Phase increment per step, [-1 ; 1]
+	DataType			_step_sin;		// -
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						OscSinCos (const OscSinCos &other);
+	OscSinCos &		operator = (const OscSinCos &other);
+	bool				operator == (const OscSinCos &other);
+	bool				operator != (const OscSinCos &other);
+
+};	// class OscSinCos
+
+
+
+#include	"OscSinCos.hpp"
+
+
+
+#endif	// OscSinCos_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/OscSinCos.hpp b/demos/spectrum/fftreal/OscSinCos.hpp
new file mode 100644
index 0000000..749aef0
--- /dev/null
+++ b/demos/spectrum/fftreal/OscSinCos.hpp
@@ -0,0 +1,122 @@
+/*****************************************************************************
+
+        OscSinCos.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (OscSinCos_CURRENT_CODEHEADER)
+	#error Recursive inclusion of OscSinCos code header.
+#endif
+#define	OscSinCos_CURRENT_CODEHEADER
+
+#if ! defined (OscSinCos_CODEHEADER_INCLUDED)
+#define	OscSinCos_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	<cmath>
+
+namespace std { }
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class T>
+OscSinCos <T>::OscSinCos ()
+:	_pos_cos (1)
+,	_pos_sin (0)
+,	_step_cos (1)
+,	_step_sin (0)
+{
+	// Nothing
+}
+
+
+
+template <class T>
+void	OscSinCos <T>::set_step (double angle_rad)
+{
+	using namespace std;
+
+	_step_cos = static_cast <DataType> (cos (angle_rad));
+	_step_sin = static_cast <DataType> (sin (angle_rad));
+}
+
+
+
+template <class T>
+typename OscSinCos <T>::DataType	OscSinCos <T>::get_cos () const
+{
+	return (_pos_cos);
+}
+
+
+
+template <class T>
+typename OscSinCos <T>::DataType	OscSinCos <T>::get_sin () const
+{
+	return (_pos_sin);
+}
+
+
+
+template <class T>
+void	OscSinCos <T>::step ()
+{
+	const DataType	old_cos = _pos_cos;
+	const DataType	old_sin = _pos_sin;
+
+	_pos_cos = old_cos * _step_cos - old_sin * _step_sin;
+	_pos_sin = old_cos * _step_sin + old_sin * _step_cos;
+}
+
+
+
+template <class T>
+void	OscSinCos <T>::clear_buffers ()
+{
+	_pos_cos = static_cast <DataType> (1);
+	_pos_sin = static_cast <DataType> (0);
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+#endif	// OscSinCos_CODEHEADER_INCLUDED
+
+#undef OscSinCos_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/TestAccuracy.h b/demos/spectrum/fftreal/TestAccuracy.h
new file mode 100644
index 0000000..4b07a6b
--- /dev/null
+++ b/demos/spectrum/fftreal/TestAccuracy.h
@@ -0,0 +1,105 @@
+/*****************************************************************************
+
+        TestAccuracy.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (TestAccuracy_HEADER_INCLUDED)
+#define	TestAccuracy_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class FO>
+class TestAccuracy
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+	typedef	typename FO::DataType	DataType;
+	typedef	long double	BigFloat;	// To get maximum accuracy during intermediate calculations
+
+   static int		perform_test_single_object (FO &fft);
+   static int		perform_test_d (FO &fft, const char *class_name_0);
+   static int		perform_test_i (FO &fft, const char *class_name_0);
+   static int		perform_test_di (FO &fft, const char *class_name_0);
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+	enum {			NBR_ACC_TESTS	= 10 * 1000 * 1000	};
+   enum {         MAX_NBR_TESTS  = 10000  };
+
+   static void		compute_tf (DataType s [], const DataType x [], long length);
+	static void		compute_itf (DataType x [], const DataType s [], long length);
+	static int		compare_vect_display (const DataType x_ptr [], const DataType y_ptr [], long len, BigFloat &max_err_rel);
+	static BigFloat
+						compute_power (const DataType x_ptr [], long len);
+	static BigFloat
+						compute_power (const DataType x_ptr [], const DataType y_ptr [], long len);
+	static void		compare_vect (const DataType x_ptr [], const DataType y_ptr [], BigFloat &power, long &max_err_pos, long len);
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						TestAccuracy ();
+						~TestAccuracy ();
+						TestAccuracy (const TestAccuracy &other);
+	TestAccuracy &	operator = (const TestAccuracy &other);
+	bool				operator == (const TestAccuracy &other);
+	bool				operator != (const TestAccuracy &other);
+
+};	// class TestAccuracy
+
+
+
+#include	"TestAccuracy.hpp"
+
+
+
+#endif	// TestAccuracy_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/TestAccuracy.hpp b/demos/spectrum/fftreal/TestAccuracy.hpp
new file mode 100644
index 0000000..5c794f7
--- /dev/null
+++ b/demos/spectrum/fftreal/TestAccuracy.hpp
@@ -0,0 +1,472 @@
+/*****************************************************************************
+
+        TestAccuracy.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (TestAccuracy_CURRENT_CODEHEADER)
+	#error Recursive inclusion of TestAccuracy code header.
+#endif
+#define	TestAccuracy_CURRENT_CODEHEADER
+
+#if ! defined (TestAccuracy_CODEHEADER_INCLUDED)
+#define	TestAccuracy_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"def.h"
+#include	"test_fnc.h"
+#include	"TestWhiteNoiseGen.h"
+
+#include	<typeinfo>
+#include	<vector>
+
+#include	<cmath>
+#include	<cstdio>
+
+
+
+static const double	TestAccuracy_LN10	= 2.3025850929940456840179914546844;
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class FO>
+int	TestAccuracy <FO>::perform_test_single_object (FO &fft)
+{
+	assert (&fft != 0);
+
+	using namespace std;
+
+	int				ret_val = 0;
+
+	const std::type_info &	ti = typeid (fft);
+	const char *	class_name_0 = ti.name ();
+
+	if (ret_val == 0)
+	{
+		ret_val = perform_test_d (fft, class_name_0);
+	}
+	if (ret_val == 0)
+	{
+		ret_val = perform_test_i (fft, class_name_0);
+	}
+	if (ret_val == 0)
+	{
+		ret_val = perform_test_di (fft, class_name_0);
+	}
+
+	if (ret_val == 0)
+	{
+		printf ("\n");
+	}
+
+	return (ret_val);
+}
+
+
+
+template <class FO>
+int	TestAccuracy <FO>::perform_test_d (FO &fft, const char *class_name_0)
+{
+	assert (&fft != 0);
+   assert (class_name_0 != 0);
+
+	using namespace std;
+
+	int				ret_val = 0;
+	const long		len = fft.get_length ();
+   const long     nbr_tests = limit (
+      NBR_ACC_TESTS / len / len,
+      1L,
+      static_cast <long> (MAX_NBR_TESTS)
+   );
+
+	printf ("Testing %s::do_fft () [%ld samples]... ", class_name_0, len);
+	fflush (stdout);
+	TestWhiteNoiseGen <DataType>	noise;
+	std::vector <DataType>	x (len);
+	std::vector <DataType>	s1 (len);
+	std::vector <DataType>	s2 (len);
+	BigFloat			err_avg = 0;
+
+	for (long test = 0; test < nbr_tests && ret_val == 0; ++ test)
+	{
+		noise.generate (&x [0], len);
+		fft.do_fft (&s1 [0], &x [0]);
+		compute_tf (&s2 [0], &x [0], len);
+
+		BigFloat			max_err;
+		compare_vect_display (&s1 [0], &s2 [0], len, max_err);
+		err_avg += max_err;
+	}
+	err_avg /= NBR_ACC_TESTS;
+
+	printf ("done.\n");
+	printf (
+		"Average maximum error: %.6f %% (%f dB)\n",
+		static_cast <double> (err_avg * 100),
+		static_cast <double> ((20 / TestAccuracy_LN10) * log (err_avg))
+	);
+
+	return (ret_val);
+}
+
+
+
+template <class FO>
+int	TestAccuracy <FO>::perform_test_i (FO &fft, const char *class_name_0)
+{
+	assert (&fft != 0);
+   assert (class_name_0 != 0);
+
+	using namespace std;
+
+	int				ret_val = 0;
+	const long		len = fft.get_length ();
+   const long     nbr_tests = limit (
+      NBR_ACC_TESTS / len / len,
+      10L,
+      static_cast <long> (MAX_NBR_TESTS)
+   );
+
+	printf ("Testing %s::do_ifft () [%ld samples]... ", class_name_0, len);
+	fflush (stdout);
+	TestWhiteNoiseGen <DataType>	noise;
+	std::vector <DataType>	s (len);
+	std::vector <DataType>	x1 (len);
+	std::vector <DataType>	x2 (len);
+	BigFloat			err_avg = 0;
+
+	for (long test = 0; test < nbr_tests && ret_val == 0; ++ test)
+	{
+		noise.generate (&s [0], len);
+		fft.do_ifft (&s [0], &x1 [0]);
+		compute_itf (&x2 [0], &s [0], len);
+
+		BigFloat			max_err;
+		compare_vect_display (&x1 [0], &x2 [0], len, max_err);
+		err_avg += max_err;
+	}
+	err_avg /= NBR_ACC_TESTS;
+
+	printf ("done.\n");
+	printf (
+		"Average maximum error: %.6f %% (%f dB)\n",
+		static_cast <double> (err_avg * 100),
+		static_cast <double> ((20 / TestAccuracy_LN10) * log (err_avg))
+	);
+
+	return (ret_val);
+}
+
+
+
+template <class FO>
+int	TestAccuracy <FO>::perform_test_di (FO &fft, const char *class_name_0)
+{
+	assert (&fft != 0);
+   assert (class_name_0 != 0);
+
+	using namespace std;
+
+	int				ret_val = 0;
+	const long		len = fft.get_length ();
+   const long     nbr_tests = limit (
+      NBR_ACC_TESTS / len / len,
+      1L,
+      static_cast <long> (MAX_NBR_TESTS)
+   );
+
+	printf (
+		"Testing %s::do_fft () / do_ifft () / rescale () [%ld samples]... ",
+		class_name_0,
+		len
+	);
+	fflush (stdout);
+	TestWhiteNoiseGen <DataType>	noise;
+	std::vector <DataType>	x (len);
+	std::vector <DataType>	s (len);
+	std::vector <DataType>	y (len);
+	BigFloat			err_avg = 0;
+
+	for (long test = 0; test < nbr_tests && ret_val == 0; ++ test)
+	{
+		noise.generate (&x [0], len);
+		fft.do_fft (&s [0], &x [0]);
+		fft.do_ifft (&s [0], &y [0]);
+		fft.rescale (&y [0]);
+
+		BigFloat			max_err;
+		compare_vect_display (&x [0], &y [0], len, max_err);
+		err_avg += max_err;
+	}
+	err_avg /= NBR_ACC_TESTS;
+
+	printf ("done.\n");
+	printf (
+		"Average maximum error: %.6f %% (%f dB)\n",
+		static_cast <double> (err_avg * 100),
+		static_cast <double> ((20 / TestAccuracy_LN10) * log (err_avg))
+	);
+
+	return (ret_val);
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+// Positive transform
+template <class FO>
+void	TestAccuracy <FO>::compute_tf (DataType s [], const DataType x [], long length)
+{
+	assert (s != 0);
+	assert (x != 0);
+	assert (length >= 2);
+	assert ((length & 1) == 0);
+
+	const long		nbr_bins = length >> 1;
+
+	// DC and Nyquist
+	BigFloat			dc = 0;
+	BigFloat			ny = 0;
+	for (long pos = 0; pos < length; pos += 2)
+	{
+		const BigFloat	even = x [pos    ];
+		const BigFloat	odd  = x [pos + 1];
+		dc += even + odd;
+		ny += even - odd;
+	}
+	s [0       ] = static_cast <DataType> (dc);
+	s [nbr_bins] = static_cast <DataType> (ny);
+
+	// Regular bins
+	for (long bin = 1; bin < nbr_bins; ++ bin)
+	{
+		BigFloat			sum_r = 0;
+		BigFloat			sum_i = 0;
+
+		const BigFloat	m = bin * static_cast <BigFloat> (2 * PI) / length;
+
+		for (long pos = 0; pos < length; ++pos)
+		{
+			using namespace std;
+
+			const BigFloat	phase = pos * m;
+			const BigFloat	e_r = cos (phase);
+			const BigFloat	e_i = sin (phase);
+
+			sum_r += x [pos] * e_r;
+			sum_i += x [pos] * e_i;
+		}
+
+		s [           bin] = static_cast <DataType> (sum_r);
+		s [nbr_bins + bin] = static_cast <DataType> (sum_i);
+	}
+}
+
+
+
+// Negative transform
+template <class FO>
+void	TestAccuracy <FO>::compute_itf (DataType x [], const DataType s [], long length)
+{
+	assert (s != 0);
+	assert (x != 0);
+	assert (length >= 2);
+	assert ((length & 1) == 0);
+
+	const long		nbr_bins = length >> 1;
+
+	// DC and Nyquist
+	BigFloat			dc = s [0       ];
+	BigFloat			ny = s [nbr_bins];
+
+	// Regular bins
+	for (long pos = 0; pos < length; ++pos)
+	{
+		BigFloat				sum = dc + ny * (1 - 2 * (pos & 1));
+
+		const BigFloat		m = pos * static_cast <BigFloat> (-2 * PI) / length;
+
+		for (long bin = 1; bin < nbr_bins; ++ bin)
+		{
+			using namespace std;
+
+			const BigFloat	phase = bin * m;
+			const BigFloat	e_r = cos (phase);
+			const BigFloat	e_i = sin (phase);
+
+			sum += 2 * (  e_r * s [bin           ]
+			            - e_i * s [bin + nbr_bins]);
+		}
+
+		x [pos] = static_cast <DataType> (sum);
+	}
+}
+
+
+
+template <class FO>
+int	TestAccuracy <FO>::compare_vect_display (const DataType x_ptr [], const DataType y_ptr [], long len, BigFloat &max_err_rel)
+{
+	assert (x_ptr != 0);
+	assert (y_ptr != 0);
+	assert (len > 0);
+	assert (&max_err_rel != 0);
+
+	using namespace std;
+
+	int				ret_val = 0;
+
+	BigFloat			power = compute_power (&x_ptr [0], &y_ptr [0], len);
+	BigFloat			power_dif;
+	long				max_err_pos;
+	compare_vect (&x_ptr [0], &y_ptr [0], power_dif, max_err_pos, len);
+
+	if (power == 0)
+	{
+		power = power_dif;
+	}
+	const BigFloat	power_err_rel = power_dif / power;
+
+	BigFloat	      max_err = 0;
+	max_err_rel = 0;
+	if (max_err_pos >= 0)
+	{
+      max_err = y_ptr [max_err_pos] - x_ptr [max_err_pos];
+		max_err_rel = 2 * fabs (max_err) / (  fabs (y_ptr [max_err_pos])
+		                                    + fabs (x_ptr [max_err_pos]));
+	}
+
+	if (power_err_rel > 0.001)
+	{
+		printf ("Power error  : %f (%.6f %%)\n",
+			static_cast <double> (power_err_rel),
+			static_cast <double> (power_err_rel * 100)
+		);
+		if (max_err_pos >= 0)
+		{
+			printf (
+				"Maximum error: %f - %f = %f (%f)\n",
+				static_cast <double> (y_ptr [max_err_pos]),
+				static_cast <double> (x_ptr [max_err_pos]),
+				static_cast <double> (max_err),
+				static_cast <double> (max_err_pos)
+			);
+		}
+	}
+
+	return (ret_val);
+}
+
+
+
+template <class FO>
+typename TestAccuracy <FO>::BigFloat	TestAccuracy <FO>::compute_power (const DataType x_ptr [], long len)
+{
+	assert (x_ptr != 0);
+	assert (len > 0);
+
+	BigFloat		power = 0;
+	for (long pos = 0; pos < len; ++pos)
+	{
+		const BigFloat	val = x_ptr [pos];
+
+		power += val * val;
+	}
+
+	using namespace std;
+
+	power = sqrt (power) / len;
+
+	return (power);
+}
+
+
+
+template <class FO>
+typename TestAccuracy <FO>::BigFloat	TestAccuracy <FO>::compute_power (const DataType x_ptr [], const DataType y_ptr [], long len)
+{
+	assert (x_ptr != 0);
+	assert (y_ptr != 0);
+	assert (len > 0);
+
+	return ((compute_power (x_ptr, len) + compute_power (y_ptr, len)) * 0.5);
+}
+
+
+
+template <class FO>
+void	TestAccuracy <FO>::compare_vect (const DataType x_ptr [], const DataType y_ptr [], BigFloat &power, long &max_err_pos, long len)
+{
+	assert (x_ptr != 0);
+	assert (y_ptr != 0);
+	assert (len > 0);
+	assert (&power != 0);
+	assert (&max_err_pos != 0);
+
+	power = 0;
+	BigFloat			max_dif2 = 0;
+	max_err_pos = -1;
+
+	for (long pos = 0; pos < len; ++pos)
+	{
+		const BigFloat	x = x_ptr [pos];
+		const BigFloat	y = y_ptr [pos];
+		const BigFloat	dif = y - x;
+		const BigFloat	dif2 = dif * dif;
+
+		power += dif2;
+		if (dif2 > max_dif2)
+		{
+			max_err_pos = pos;
+			max_dif2 = dif2;
+		}
+	}
+
+	using namespace std;
+
+	power = sqrt (power) / len;
+}
+
+
+
+#endif	// TestAccuracy_CODEHEADER_INCLUDED
+
+#undef TestAccuracy_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/TestHelperFixLen.h b/demos/spectrum/fftreal/TestHelperFixLen.h
new file mode 100644
index 0000000..ecff96d
--- /dev/null
+++ b/demos/spectrum/fftreal/TestHelperFixLen.h
@@ -0,0 +1,93 @@
+/*****************************************************************************
+
+        TestHelperFixLen.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (TestHelperFixLen_HEADER_INCLUDED)
+#define	TestHelperFixLen_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"FFTRealFixLen.h"
+
+
+
+template <int L>
+class TestHelperFixLen
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+	typedef  FFTRealFixLen <L> FftType;
+
+   static void    perform_test_accuracy (int &ret_val);
+   static void    perform_test_speed (int &ret_val);
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						TestHelperFixLen ();
+						~TestHelperFixLen ();
+						TestHelperFixLen (const TestHelperFixLen &other);
+	TestHelperFixLen &
+						operator = (const TestHelperFixLen &other);
+	bool				operator == (const TestHelperFixLen &other);
+	bool				operator != (const TestHelperFixLen &other);
+
+};	// class TestHelperFixLen
+
+
+
+#include	"TestHelperFixLen.hpp"
+
+
+
+#endif	// TestHelperFixLen_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/TestHelperFixLen.hpp b/demos/spectrum/fftreal/TestHelperFixLen.hpp
new file mode 100644
index 0000000..25048b9
--- /dev/null
+++ b/demos/spectrum/fftreal/TestHelperFixLen.hpp
@@ -0,0 +1,93 @@
+/*****************************************************************************
+
+        TestHelperFixLen.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (TestHelperFixLen_CURRENT_CODEHEADER)
+	#error Recursive inclusion of TestHelperFixLen code header.
+#endif
+#define	TestHelperFixLen_CURRENT_CODEHEADER
+
+#if ! defined (TestHelperFixLen_CODEHEADER_INCLUDED)
+#define	TestHelperFixLen_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"test_settings.h"
+
+#include	"TestAccuracy.h"
+#if defined (test_settings_SPEED_TEST_ENABLED)
+	#include	"TestSpeed.h"
+#endif
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <int L>
+void	TestHelperFixLen <L>::perform_test_accuracy (int &ret_val)
+{
+   if (ret_val == 0)
+   {
+		FftType			fft;
+      ret_val = TestAccuracy <FftType>::perform_test_single_object (fft);
+   }
+}
+
+
+
+template <int L>
+void	TestHelperFixLen <L>::perform_test_speed (int &ret_val)
+{
+#if defined (test_settings_SPEED_TEST_ENABLED)
+
+   if (ret_val == 0)
+   {
+		FftType			fft;
+      ret_val = TestSpeed <FftType>::perform_test_single_object (fft);
+   }
+
+#endif
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+#endif	// TestHelperFixLen_CODEHEADER_INCLUDED
+
+#undef TestHelperFixLen_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/TestHelperNormal.h b/demos/spectrum/fftreal/TestHelperNormal.h
new file mode 100644
index 0000000..a7bff5c
--- /dev/null
+++ b/demos/spectrum/fftreal/TestHelperNormal.h
@@ -0,0 +1,94 @@
+/*****************************************************************************
+
+        TestHelperNormal.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (TestHelperNormal_HEADER_INCLUDED)
+#define	TestHelperNormal_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"FFTReal.h"
+
+
+
+template <class DT>
+class TestHelperNormal
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+	typedef	DT	DataType;
+	typedef	FFTReal <DataType>	FftType;
+
+   static void    perform_test_accuracy (int &ret_val);
+   static void    perform_test_speed (int &ret_val);
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						TestHelperNormal ();
+						~TestHelperNormal ();
+						TestHelperNormal (const TestHelperNormal &other);
+	TestHelperNormal &
+						operator = (const TestHelperNormal &other);
+	bool				operator == (const TestHelperNormal &other);
+	bool				operator != (const TestHelperNormal &other);
+
+};	// class TestHelperNormal
+
+
+
+#include	"TestHelperNormal.hpp"
+
+
+
+#endif	// TestHelperNormal_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/TestHelperNormal.hpp b/demos/spectrum/fftreal/TestHelperNormal.hpp
new file mode 100644
index 0000000..e037696
--- /dev/null
+++ b/demos/spectrum/fftreal/TestHelperNormal.hpp
@@ -0,0 +1,99 @@
+/*****************************************************************************
+
+        TestHelperNormal.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (TestHelperNormal_CURRENT_CODEHEADER)
+	#error Recursive inclusion of TestHelperNormal code header.
+#endif
+#define	TestHelperNormal_CURRENT_CODEHEADER
+
+#if ! defined (TestHelperNormal_CODEHEADER_INCLUDED)
+#define	TestHelperNormal_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"test_settings.h"
+
+#include	"TestAccuracy.h"
+#if defined (test_settings_SPEED_TEST_ENABLED)
+	#include	"TestSpeed.h"
+#endif
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class DT>
+void	TestHelperNormal <DT>::perform_test_accuracy (int &ret_val)
+{
+	const int		len_arr [] = { 1, 2, 3, 4, 7, 8, 10, 12 };
+	const int		nbr_len = sizeof (len_arr) / sizeof (len_arr [0]);
+	for (int k = 0; k < nbr_len && ret_val == 0; ++k)
+	{
+		const long		len = 1L << (len_arr [k]);
+		FftType			fft (len);
+		ret_val = TestAccuracy <FftType>::perform_test_single_object (fft);
+	}
+}
+
+
+
+template <class DT>
+void	TestHelperNormal <DT>::perform_test_speed (int &ret_val)
+{
+#if defined (test_settings_SPEED_TEST_ENABLED)
+
+	const int		len_arr [] = { 1, 2, 3, 4, 7, 8, 10, 12, 14, 16, 18, 20, 22 };
+	const int		nbr_len = sizeof (len_arr) / sizeof (len_arr [0]);
+	for (int k = 0; k < nbr_len && ret_val == 0; ++k)
+	{
+		const long		len = 1L << (len_arr [k]);
+		FftType			fft (len);
+		ret_val = TestSpeed <FftType>::perform_test_single_object (fft);
+	}
+
+#endif
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+#endif	// TestHelperNormal_CODEHEADER_INCLUDED
+
+#undef TestHelperNormal_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/TestSpeed.h b/demos/spectrum/fftreal/TestSpeed.h
new file mode 100644
index 0000000..2295781
--- /dev/null
+++ b/demos/spectrum/fftreal/TestSpeed.h
@@ -0,0 +1,95 @@
+/*****************************************************************************
+
+        TestSpeed.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (TestSpeed_HEADER_INCLUDED)
+#define	TestSpeed_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class FO>
+class TestSpeed
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+	typedef	typename FO::DataType	DataType;
+
+   static int		perform_test_single_object (FO &fft);
+   static int		perform_test_d (FO &fft, const char *class_name_0);
+   static int		perform_test_i (FO &fft, const char *class_name_0);
+   static int		perform_test_di (FO &fft, const char *class_name_0);
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+	enum {			NBR_SPD_TESTS	= 10 * 1000 * 1000	};
+   enum {         MAX_NBR_TESTS  = 10000  };
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						TestSpeed ();
+						~TestSpeed ();
+						TestSpeed (const TestSpeed &other);
+	TestSpeed &		operator = (const TestSpeed &other);
+	bool				operator == (const TestSpeed &other);
+	bool				operator != (const TestSpeed &other);
+
+};	// class TestSpeed
+
+
+
+#include	"TestSpeed.hpp"
+
+
+
+#endif	// TestSpeed_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/TestSpeed.hpp b/demos/spectrum/fftreal/TestSpeed.hpp
new file mode 100644
index 0000000..e716b2a
--- /dev/null
+++ b/demos/spectrum/fftreal/TestSpeed.hpp
@@ -0,0 +1,223 @@
+/*****************************************************************************
+
+        TestSpeed.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (TestSpeed_CURRENT_CODEHEADER)
+	#error Recursive inclusion of TestSpeed code header.
+#endif
+#define	TestSpeed_CURRENT_CODEHEADER
+
+#if ! defined (TestSpeed_CODEHEADER_INCLUDED)
+#define	TestSpeed_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"test_fnc.h"
+#include	"stopwatch/StopWatch.h"
+#include	"TestWhiteNoiseGen.h"
+
+#include	<typeinfo>
+
+#include	<cstdio>
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class FO>
+int	TestSpeed <FO>::perform_test_single_object (FO &fft)
+{
+	assert (&fft != 0);
+
+   int            ret_val = 0;
+
+	const std::type_info &	ti = typeid (fft);
+	const char *	class_name_0 = ti.name ();
+
+   if (ret_val == 0)
+   {
+	   perform_test_d (fft, class_name_0);
+   }
+   if (ret_val == 0)
+   {
+	   perform_test_i (fft, class_name_0);
+   }
+	if (ret_val == 0)
+   {
+      perform_test_di (fft, class_name_0);
+   }
+
+   if (ret_val == 0)
+   {
+      printf ("\n");
+   }
+
+   return (ret_val);
+}
+
+
+
+template <class FO>
+int	TestSpeed <FO>::perform_test_d (FO &fft, const char *class_name_0)
+{
+	assert (&fft != 0);
+   assert (class_name_0 != 0);
+
+	const long		len = fft.get_length ();
+   const long     nbr_tests = limit (
+      static_cast <long> (NBR_SPD_TESTS / len / len),
+      1L,
+      static_cast <long> (MAX_NBR_TESTS)
+   );
+
+	TestWhiteNoiseGen <DataType>	noise;
+	std::vector <DataType>	x (len, 0);
+	std::vector <DataType>	s (len);
+	noise.generate (&x [0], len);
+
+   printf (
+		"%s::do_fft () speed test [%ld samples]... ",
+		class_name_0,
+		len
+	);
+	fflush (stdout);
+
+	stopwatch::StopWatch	chrono;
+	chrono.start ();
+	for (long test = 0; test < nbr_tests; ++ test)
+	{
+		fft.do_fft (&s [0], &x [0]);
+		chrono.stop_lap ();
+	}
+
+	printf ("%.1f clocks/sample\n", chrono.get_time_best_lap (len));
+
+	return (0);
+}
+
+
+
+template <class FO>
+int	TestSpeed <FO>::perform_test_i (FO &fft, const char *class_name_0)
+{
+	assert (&fft != 0);
+   assert (class_name_0 != 0);
+
+	const long		len = fft.get_length ();
+   const long     nbr_tests = limit (
+      static_cast <long> (NBR_SPD_TESTS / len / len),
+      1L,
+      static_cast <long> (MAX_NBR_TESTS)
+   );
+
+	TestWhiteNoiseGen <DataType>	noise;
+	std::vector <DataType>	x (len);
+	std::vector <DataType>	s (len, 0);
+	noise.generate (&s [0], len);
+
+   printf (
+		"%s::do_ifft () speed test [%ld samples]... ",
+		class_name_0,
+		len
+	);
+	fflush (stdout);
+
+	stopwatch::StopWatch	chrono;
+	chrono.start ();
+	for (long test = 0; test < nbr_tests; ++ test)
+	{
+		fft.do_ifft (&s [0], &x [0]);
+		chrono.stop_lap ();
+	}
+
+	printf ("%.1f clocks/sample\n", chrono.get_time_best_lap (len));
+
+	return (0);
+}
+
+
+
+template <class FO>
+int	TestSpeed <FO>::perform_test_di (FO &fft, const char *class_name_0)
+{
+	assert (&fft != 0);
+   assert (class_name_0 != 0);
+
+	const long		len = fft.get_length ();
+   const long     nbr_tests = limit (
+      static_cast <long> (NBR_SPD_TESTS / len / len),
+      1L,
+      static_cast <long> (MAX_NBR_TESTS)
+   );
+
+	TestWhiteNoiseGen <DataType>	noise;
+	std::vector <DataType>	x (len, 0);
+	std::vector <DataType>	s (len);
+	std::vector <DataType>	y (len);
+	noise.generate (&x [0], len);
+
+   printf (
+		"%s::do_fft () / do_ifft () / rescale () speed test [%ld samples]... ",
+		class_name_0,
+		len
+	);
+	fflush (stdout);
+
+	stopwatch::StopWatch	chrono;
+
+	chrono.start ();
+	for (long test = 0; test < nbr_tests; ++ test)
+	{
+		fft.do_fft (&s [0], &x [0]);
+		fft.do_ifft (&s [0], &y [0]);
+		fft.rescale (&y [0]);
+		chrono.stop_lap ();
+	}
+
+	printf ("%.1f clocks/sample\n", chrono.get_time_best_lap (len));
+
+	return (0);
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+#endif	// TestSpeed_CODEHEADER_INCLUDED
+
+#undef TestSpeed_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/TestWhiteNoiseGen.h b/demos/spectrum/fftreal/TestWhiteNoiseGen.h
new file mode 100644
index 0000000..d815f8e
--- /dev/null
+++ b/demos/spectrum/fftreal/TestWhiteNoiseGen.h
@@ -0,0 +1,95 @@
+/*****************************************************************************
+
+        TestWhiteNoiseGen.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (TestWhiteNoiseGen_HEADER_INCLUDED)
+#define	TestWhiteNoiseGen_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class DT>
+class TestWhiteNoiseGen
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+	typedef	DT	DataType;
+
+						TestWhiteNoiseGen ();
+	virtual			~TestWhiteNoiseGen () {}
+
+	void				generate (DataType data_ptr [], long len);
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+	typedef	unsigned long	StateType;
+
+	StateType		_rand_state;
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						TestWhiteNoiseGen (const TestWhiteNoiseGen &other);
+	TestWhiteNoiseGen &
+						operator = (const TestWhiteNoiseGen &other);
+	bool				operator == (const TestWhiteNoiseGen &other);
+	bool				operator != (const TestWhiteNoiseGen &other);
+
+};	// class TestWhiteNoiseGen
+
+
+
+#include	"TestWhiteNoiseGen.hpp"
+
+
+
+#endif	// TestWhiteNoiseGen_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/TestWhiteNoiseGen.hpp b/demos/spectrum/fftreal/TestWhiteNoiseGen.hpp
new file mode 100644
index 0000000..13b7eb3
--- /dev/null
+++ b/demos/spectrum/fftreal/TestWhiteNoiseGen.hpp
@@ -0,0 +1,91 @@
+/*****************************************************************************
+
+        TestWhiteNoiseGen.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (TestWhiteNoiseGen_CURRENT_CODEHEADER)
+	#error Recursive inclusion of TestWhiteNoiseGen code header.
+#endif
+#define	TestWhiteNoiseGen_CURRENT_CODEHEADER
+
+#if ! defined (TestWhiteNoiseGen_CODEHEADER_INCLUDED)
+#define	TestWhiteNoiseGen_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class DT>
+TestWhiteNoiseGen <DT>::TestWhiteNoiseGen ()
+:	_rand_state (0)
+{
+	_rand_state = reinterpret_cast <StateType> (this);
+}
+
+
+
+template <class DT>
+void	TestWhiteNoiseGen <DT>::generate (DataType data_ptr [], long len)
+{
+	assert (data_ptr != 0);
+	assert (len > 0);
+
+	const DataType	one = static_cast <DataType> (1);
+	const DataType	mul = one / static_cast <DataType> (0x80000000UL);
+
+	long				pos = 0;
+	do
+	{
+		const DataType	x = static_cast <DataType> (_rand_state & 0xFFFFFFFFUL);
+		data_ptr [pos] = x * mul - one;
+
+		_rand_state = _rand_state * 1234567UL + 890123UL;
+
+		++ pos;
+	}
+	while (pos < len);
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+#endif	// TestWhiteNoiseGen_CODEHEADER_INCLUDED
+
+#undef TestWhiteNoiseGen_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/bwins/fftrealu.def b/demos/spectrum/fftreal/bwins/fftrealu.def
new file mode 100644
index 0000000..7a79397
--- /dev/null
+++ b/demos/spectrum/fftreal/bwins/fftrealu.def
@@ -0,0 +1,5 @@
+EXPORTS
+	??0FFTRealWrapper@@QAE@XZ @ 1 NONAME ; FFTRealWrapper::FFTRealWrapper(void)
+	??1FFTRealWrapper@@QAE@XZ @ 2 NONAME ; FFTRealWrapper::~FFTRealWrapper(void)
+	?calculateFFT@FFTRealWrapper@@QAEXQAMQBM@Z @ 3 NONAME ; void FFTRealWrapper::calculateFFT(float * const, float const * const)
+
diff --git a/demos/spectrum/fftreal/def.h b/demos/spectrum/fftreal/def.h
new file mode 100644
index 0000000..99c545f
--- /dev/null
+++ b/demos/spectrum/fftreal/def.h
@@ -0,0 +1,60 @@
+/*****************************************************************************
+
+        def.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (def_HEADER_INCLUDED)
+#define	def_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+
+const double	PI		= 3.1415926535897932384626433832795;
+const double	SQRT2	= 1.41421356237309514547462185873883;
+
+#if defined (_MSC_VER)
+
+	#define	FORCEINLINE	__forceinline
+
+#else
+
+	#define	FORCEINLINE	inline
+
+#endif
+
+
+
+#endif	// def_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/eabi/fftrealu.def b/demos/spectrum/fftreal/eabi/fftrealu.def
new file mode 100644
index 0000000..f95a441
--- /dev/null
+++ b/demos/spectrum/fftreal/eabi/fftrealu.def
@@ -0,0 +1,7 @@
+EXPORTS
+	_ZN14FFTRealWrapper12calculateFFTEPfPKf @ 1 NONAME
+	_ZN14FFTRealWrapperC1Ev @ 2 NONAME
+	_ZN14FFTRealWrapperC2Ev @ 3 NONAME
+	_ZN14FFTRealWrapperD1Ev @ 4 NONAME
+	_ZN14FFTRealWrapperD2Ev @ 5 NONAME
+
diff --git a/demos/spectrum/fftreal/fftreal.pas b/demos/spectrum/fftreal/fftreal.pas
new file mode 100644
index 0000000..ea63754
--- /dev/null
+++ b/demos/spectrum/fftreal/fftreal.pas
@@ -0,0 +1,661 @@
+(*****************************************************************************
+
+        DIGITAL SIGNAL PROCESSING TOOLS
+        Version 1.03, 2001/06/15
+        (c) 1999 - Laurent de Soras
+
+        FFTReal.h
+        Fourier transformation of real number arrays.
+        Portable ISO C++
+
+------------------------------------------------------------------------------
+
+	LEGAL
+
+	Source code may be freely used for any purpose, including commercial
+	applications. Programs must display in their "About" dialog-box (or
+	documentation) a text telling they use these routines by Laurent de Soras.
+	Modified source code can be distributed, but modifications must be clearly
+	indicated.
+
+	CONTACT
+
+	Laurent de Soras
+	92 avenue Albert 1er
+	92500 Rueil-Malmaison
+	France
+
+	ldesoras@club-internet.fr
+
+------------------------------------------------------------------------------
+
+        Translation to ObjectPascal by :
+          Frederic Vanmol
+          frederic@axiworld.be
+
+*****************************************************************************)
+
+
+unit
+    FFTReal;
+
+interface
+
+uses
+    Windows;
+
+(* Change this typedef to use a different floating point type in your FFTs
+	(i.e. float, double or long double). *)
+type
+    pflt_t = ^flt_t;
+    flt_t = single;
+
+    pflt_array = ^flt_array;
+    flt_array = array[0..0] of flt_t;
+
+    plongarray = ^longarray;
+    longarray = array[0..0] of longint;
+
+const
+     sizeof_flt : longint = SizeOf(flt_t);
+
+
+
+type
+    // Bit reversed look-up table nested class
+    TBitReversedLUT = class
+    private
+      _ptr : plongint;
+    public
+      constructor Create(const nbr_bits: integer);
+      destructor Destroy; override;
+      function get_ptr: plongint;
+    end;
+
+    // Trigonometric look-up table nested class
+    TTrigoLUT = class
+    private
+      _ptr : pflt_t;
+    public
+      constructor Create(const nbr_bits: integer);
+      destructor Destroy; override;
+      function get_ptr(const level: integer): pflt_t;
+    end;
+
+    TFFTReal = class
+    private
+      _bit_rev_lut  : TBitReversedLUT;
+      _trigo_lut    : TTrigoLUT;
+      _sqrt2_2      : flt_t;
+      _length       : longint;
+      _nbr_bits     : integer;
+      _buffer_ptr   : pflt_t;
+    public
+      constructor Create(const length: longint);
+      destructor Destroy; override;
+
+      procedure do_fft(f: pflt_array; const x: pflt_array);
+      procedure do_ifft(const f: pflt_array; x: pflt_array);
+      procedure rescale(x: pflt_array);
+    end;
+
+
+
+
+
+
+
+implementation
+
+uses
+    Math;
+
+{ TBitReversedLUT }
+
+constructor TBitReversedLUT.Create(const nbr_bits: integer);
+var
+   length   : longint;
+   cnt      : longint;
+   br_index : longint;
+   bit      : longint;
+begin
+  inherited Create;
+
+  length := 1 shl nbr_bits;
+  GetMem(_ptr, length*SizeOf(longint));
+
+  br_index := 0;
+  plongarray(_ptr)^[0] := 0;
+  for cnt := 1 to length-1 do
+  begin
+    // ++br_index (bit reversed)
+    bit := length shr 1;
+    br_index := br_index xor bit;
+    while br_index and bit = 0 do
+    begin
+      bit := bit shr 1;
+      br_index := br_index xor bit;
+    end;
+
+    plongarray(_ptr)^[cnt] := br_index;
+  end;
+end;
+
+destructor TBitReversedLUT.Destroy;
+begin
+  FreeMem(_ptr);
+  _ptr := nil;
+  inherited;
+end;
+
+function TBitReversedLUT.get_ptr: plongint;
+begin
+  Result := _ptr;
+end;
+
+{ TTrigLUT }
+
+constructor TTrigoLUT.Create(const nbr_bits: integer);
+var
+   total_len : longint;
+   PI        : double;
+   level     : integer;
+   level_len : longint;
+   level_ptr : pflt_array;
+   mul       : double;
+   i         : longint;
+begin
+  inherited Create;
+
+  _ptr := nil;
+
+  if (nbr_bits > 3) then
+  begin
+    total_len := (1 shl (nbr_bits - 1)) - 4;
+    GetMem(_ptr, total_len * sizeof_flt);
+
+    PI := ArcTan(1) * 4;
+    for level := 3 to nbr_bits-1 do
+    begin
+      level_len := 1 shl (level - 1);
+      level_ptr := pointer(get_ptr(level));
+      mul := PI / (level_len shl 1);
+
+      for i := 0 to level_len-1 do
+        level_ptr^[i] := cos(i * mul);
+    end;
+  end;
+end;
+
+destructor TTrigoLUT.Destroy;
+begin
+  FreeMem(_ptr);
+  _ptr := nil;
+  inherited;
+end;
+
+function TTrigoLUT.get_ptr(const level: integer): pflt_t;
+var
+   tempp : pflt_t;
+begin
+  tempp := _ptr;
+  inc(tempp, (1 shl (level-1)) - 4);
+  Result := tempp;
+end;
+
+{ TFFTReal }
+
+constructor TFFTReal.Create(const length: longint);
+begin
+  inherited Create;
+
+  _length := length;
+  _nbr_bits := Floor(Ln(length) / Ln(2) + 0.5);
+  _bit_rev_lut := TBitReversedLUT.Create(Floor(Ln(length) / Ln(2) + 0.5));
+  _trigo_lut := TTrigoLUT.Create(Floor(Ln(length) / Ln(2) + 0.05));
+  _sqrt2_2 := Sqrt(2) * 0.5;
+
+  _buffer_ptr := nil;
+  if _nbr_bits > 2 then
+    GetMem(_buffer_ptr, _length * sizeof_flt);
+end;
+
+destructor TFFTReal.Destroy;
+begin
+  if _buffer_ptr <> nil then
+  begin
+    FreeMem(_buffer_ptr);
+    _buffer_ptr := nil;
+  end;
+
+  _bit_rev_lut.Free;
+  _bit_rev_lut := nil;
+  _trigo_lut.Free;
+  _trigo_lut := nil;
+
+  inherited;       
+end;
+
+(*==========================================================================*/
+/*      Name: do_fft                                                        */
+/*      Description: Compute the FFT of the array.                          */
+/*      Input parameters:                                                   */
+/*        - x: pointer on the source array (time).                          */
+/*      Output parameters:                                                  */
+/*        - f: pointer on the destination array (frequencies).              */
+/*             f [0...length(x)/2] = real values,                           */
+/*             f [length(x)/2+1...length(x)-1] = imaginary values of        */
+/*               coefficents 1...length(x)/2-1.                             */
+/*==========================================================================*)
+procedure TFFTReal.do_fft(f: pflt_array; const x: pflt_array);
+var
+   sf, df     : pflt_array;
+   pass       : integer;
+   nbr_coef   : longint;
+   h_nbr_coef : longint;
+   d_nbr_coef : longint;
+   coef_index : longint;
+   bit_rev_lut_ptr : plongarray;
+   rev_index_0 : longint;
+   rev_index_1 : longint;
+   rev_index_2 : longint;
+   rev_index_3 : longint;
+   df2         : pflt_array;
+   n1, n2, n3  : integer;
+   sf_0, sf_2  : flt_t;
+   sqrt2_2     : flt_t;
+   v           : flt_t;
+   cos_ptr     : pflt_array;
+   i           : longint;
+   sf1r, sf2r  : pflt_array;
+   dfr, dfi    : pflt_array;
+   sf1i, sf2i  : pflt_array;
+   c, s        : flt_t;
+   temp_ptr    : pflt_array;
+   b_0, b_2    : flt_t;
+begin
+  n1 := 1;
+  n2 := 2;
+  n3 := 3;
+
+  (*______________________________________________
+   *
+   * General case
+   *______________________________________________
+   *)
+
+  if _nbr_bits > 2 then
+  begin
+    if _nbr_bits and 1 <> 0 then
+    begin
+      df := pointer(_buffer_ptr);
+      sf := f;
+    end
+    else
+    begin
+      df := f;
+      sf := pointer(_buffer_ptr);
+    end;
+
+    //
+    // Do the transformation in several passes
+    //
+
+    // First and second pass at once
+    bit_rev_lut_ptr := pointer(_bit_rev_lut.get_ptr);
+    coef_index := 0;
+
+    repeat
+      rev_index_0 := bit_rev_lut_ptr^[coef_index];
+      rev_index_1 := bit_rev_lut_ptr^[coef_index + 1];
+      rev_index_2 := bit_rev_lut_ptr^[coef_index + 2];
+      rev_index_3 := bit_rev_lut_ptr^[coef_index + 3];
+
+      df2 := pointer(longint(df) + (coef_index*sizeof_flt));
+      df2^[n1] := x^[rev_index_0] - x^[rev_index_1];
+      df2^[n3] := x^[rev_index_2] - x^[rev_index_3];
+
+      sf_0 := x^[rev_index_0] + x^[rev_index_1];
+      sf_2 := x^[rev_index_2] + x^[rev_index_3];
+
+      df2^[0] := sf_0 + sf_2;
+      df2^[n2] := sf_0 - sf_2;
+
+      inc(coef_index, 4);
+    until (coef_index >= _length);
+
+
+    // Third pass
+    coef_index := 0;
+    sqrt2_2 := _sqrt2_2;
+
+    repeat
+      sf^[coef_index] := df^[coef_index] + df^[coef_index + 4];
+      sf^[coef_index + 4] := df^[coef_index] - df^[coef_index + 4];
+      sf^[coef_index + 2] := df^[coef_index + 2];
+      sf^[coef_index + 6] := df^[coef_index + 6];
+
+      v := (df [coef_index + 5] - df^[coef_index + 7]) * sqrt2_2;
+      sf^[coef_index + 1] := df^[coef_index + 1] + v;
+      sf^[coef_index + 3] := df^[coef_index + 1] - v;
+
+      v := (df^[coef_index + 5] + df^[coef_index + 7]) * sqrt2_2;
+      sf [coef_index + 5] := v + df^[coef_index + 3];
+      sf [coef_index + 7] := v - df^[coef_index + 3];
+
+      inc(coef_index, 8);
+    until (coef_index >= _length);
+
+
+    // Next pass
+    for pass := 3 to _nbr_bits-1 do
+    begin
+      coef_index := 0;
+      nbr_coef := 1 shl pass;
+      h_nbr_coef := nbr_coef shr 1;
+      d_nbr_coef := nbr_coef shl 1;
+
+      cos_ptr := pointer(_trigo_lut.get_ptr(pass));
+      repeat
+        sf1r := pointer(longint(sf) + (coef_index * sizeof_flt));
+        sf2r := pointer(longint(sf1r) + (nbr_coef * sizeof_flt));
+        dfr := pointer(longint(df) + (coef_index * sizeof_flt));
+        dfi := pointer(longint(dfr) + (nbr_coef * sizeof_flt));
+
+        // Extreme coefficients are always real
+        dfr^[0] := sf1r^[0] + sf2r^[0];
+        dfi^[0] := sf1r^[0] - sf2r^[0];   // dfr [nbr_coef] =
+        dfr^[h_nbr_coef] := sf1r^[h_nbr_coef];
+        dfi^[h_nbr_coef] := sf2r^[h_nbr_coef];
+
+        // Others are conjugate complex numbers
+        sf1i := pointer(longint(sf1r) + (h_nbr_coef * sizeof_flt));
+        sf2i := pointer(longint(sf1i) + (nbr_coef * sizeof_flt));
+
+        for i := 1 to h_nbr_coef-1 do
+        begin
+          c := cos_ptr^[i];               // cos (i*PI/nbr_coef);
+          s := cos_ptr^[h_nbr_coef - i];  // sin (i*PI/nbr_coef);
+
+          v := sf2r^[i] * c - sf2i^[i] * s;
+          dfr^[i] := sf1r^[i] + v;
+          dfi^[-i] := sf1r^[i] - v;	// dfr [nbr_coef - i] =
+
+          v := sf2r^[i] * s + sf2i^[i] * c;
+          dfi^[i] := v + sf1i^[i];
+          dfi^[nbr_coef - i] := v - sf1i^[i];
+        end;
+
+        inc(coef_index, d_nbr_coef);
+      until (coef_index >= _length);
+
+      // Prepare to the next pass
+      temp_ptr := df;
+      df := sf;
+      sf := temp_ptr;
+    end;
+  end
+
+  (*______________________________________________
+   *
+   * Special cases
+   *______________________________________________
+   *)
+
+  // 4-point FFT
+  else if _nbr_bits = 2 then
+  begin
+    f^[n1] := x^[0] - x^[n2];
+    f^[n3] := x^[n1] - x^[n3];
+
+    b_0 := x^[0] + x^[n2];
+    b_2 := x^[n1] + x^[n3];
+
+    f^[0] := b_0 + b_2;
+    f^[n2] := b_0 - b_2;
+  end
+
+  // 2-point FFT
+  else if _nbr_bits = 1 then
+  begin
+    f^[0] := x^[0] + x^[n1];
+    f^[n1] := x^[0] - x^[n1];
+  end
+
+  // 1-point FFT
+  else
+    f^[0] := x^[0];
+end;
+
+
+(*==========================================================================*/
+/*      Name: do_ifft                                                       */
+/*      Description: Compute the inverse FFT of the array. Notice that      */
+/*                   IFFT (FFT (x)) = x * length (x). Data must be          */
+/*                   post-scaled.                                           */
+/*      Input parameters:                                                   */
+/*        - f: pointer on the source array (frequencies).                   */
+/*             f [0...length(x)/2] = real values,                           */
+/*             f [length(x)/2+1...length(x)-1] = imaginary values of        */
+/*               coefficents 1...length(x)/2-1.                             */
+/*      Output parameters:                                                  */
+/*        - x: pointer on the destination array (time).                     */
+/*==========================================================================*)
+procedure TFFTReal.do_ifft(const f: pflt_array; x: pflt_array);
+var
+   n1, n2, n3      : integer;
+   n4, n5, n6, n7  : integer;
+   sf, df, df_temp : pflt_array;
+   pass            : integer;
+   nbr_coef        : longint;
+   h_nbr_coef      : longint;
+   d_nbr_coef      : longint;
+   coef_index      : longint;
+   cos_ptr         : pflt_array;
+   i               : longint;
+   sfr, sfi        : pflt_array;
+   df1r, df2r      : pflt_array;
+   df1i, df2i      : pflt_array;
+   c, s, vr, vi    : flt_t;
+   temp_ptr        : pflt_array;
+   sqrt2_2         : flt_t;
+   bit_rev_lut_ptr : plongarray;
+   sf2             : pflt_array;
+   b_0, b_1, b_2, b_3 : flt_t;
+begin
+  n1 := 1;
+  n2 := 2;
+  n3 := 3;
+  n4 := 4;
+  n5 := 5;
+  n6 := 6;
+  n7 := 7;
+
+  (*______________________________________________
+   *
+   * General case
+   *______________________________________________
+   *)
+
+  if _nbr_bits > 2 then
+  begin
+    sf := f;
+
+    if _nbr_bits and 1 <> 0 then
+    begin
+      df := pointer(_buffer_ptr);
+      df_temp := x;
+    end
+    else
+    begin
+      df := x;
+      df_temp := pointer(_buffer_ptr);
+    end;
+
+    // Do the transformation in several pass
+
+    // First pass
+    for pass := _nbr_bits-1 downto 3 do
+    begin
+      coef_index := 0;
+      nbr_coef := 1 shl pass;
+      h_nbr_coef := nbr_coef shr 1;
+      d_nbr_coef := nbr_coef shl 1;
+
+      cos_ptr := pointer(_trigo_lut.get_ptr(pass));
+
+      repeat
+        sfr := pointer(longint(sf) + (coef_index*sizeof_flt));
+        sfi := pointer(longint(sfr) + (nbr_coef*sizeof_flt));
+        df1r := pointer(longint(df) + (coef_index*sizeof_flt));
+        df2r := pointer(longint(df1r) + (nbr_coef*sizeof_flt));
+
+        // Extreme coefficients are always real
+        df1r^[0] := sfr^[0] + sfi^[0];		// + sfr [nbr_coef]
+        df2r^[0] := sfr^[0] - sfi^[0];		// - sfr [nbr_coef]
+        df1r^[h_nbr_coef] := sfr^[h_nbr_coef] * 2;
+        df2r^[h_nbr_coef] := sfi^[h_nbr_coef] * 2;
+
+        // Others are conjugate complex numbers
+        df1i := pointer(longint(df1r) + (h_nbr_coef*sizeof_flt));
+        df2i := pointer(longint(df1i) + (nbr_coef*sizeof_flt));
+
+        for i := 1 to h_nbr_coef-1 do
+        begin
+          df1r^[i] := sfr^[i] + sfi^[-i];		// + sfr [nbr_coef - i]
+          df1i^[i] := sfi^[i] - sfi^[nbr_coef - i];
+
+          c := cos_ptr^[i];					// cos (i*PI/nbr_coef);
+          s := cos_ptr^[h_nbr_coef - i];	// sin (i*PI/nbr_coef);
+          vr := sfr^[i] - sfi^[-i];		// - sfr [nbr_coef - i]
+          vi := sfi^[i] + sfi^[nbr_coef - i];
+
+          df2r^[i] := vr * c + vi * s;
+          df2i^[i] := vi * c - vr * s;
+        end;
+
+        inc(coef_index, d_nbr_coef);
+      until (coef_index >= _length);
+
+
+      // Prepare to the next pass 
+      if (pass < _nbr_bits - 1) then
+      begin
+        temp_ptr := df;
+        df := sf;
+        sf := temp_ptr;
+      end
+      else
+      begin
+        sf := df;
+        df := df_temp;
+      end
+    end;
+
+    // Antepenultimate pass
+    sqrt2_2 := _sqrt2_2;
+    coef_index := 0;
+
+    repeat
+      df^[coef_index] := sf^[coef_index] + sf^[coef_index + 4];
+      df^[coef_index + 4] := sf^[coef_index] - sf^[coef_index + 4];
+      df^[coef_index + 2] := sf^[coef_index + 2] * 2;
+      df^[coef_index + 6] := sf^[coef_index + 6] * 2;
+
+      df^[coef_index + 1] := sf^[coef_index + 1] + sf^[coef_index + 3];
+      df^[coef_index + 3] := sf^[coef_index + 5] - sf^[coef_index + 7];
+
+      vr := sf^[coef_index + 1] - sf^[coef_index + 3];
+      vi := sf^[coef_index + 5] + sf^[coef_index + 7];
+
+      df^[coef_index + 5] := (vr + vi) * sqrt2_2;
+      df^[coef_index + 7] := (vi - vr) * sqrt2_2;
+
+      inc(coef_index, 8);
+    until (coef_index >= _length);
+
+
+    // Penultimate and last pass at once 
+    coef_index := 0;
+    bit_rev_lut_ptr := pointer(_bit_rev_lut.get_ptr);
+    sf2 := df;
+
+    repeat
+      b_0 := sf2^[0] + sf2^[n2];
+      b_2 := sf2^[0] - sf2^[n2];
+      b_1 := sf2^[n1] * 2;
+      b_3 := sf2^[n3] * 2;
+
+      x^[bit_rev_lut_ptr^[0]] := b_0 + b_1;
+      x^[bit_rev_lut_ptr^[n1]] := b_0 - b_1;
+      x^[bit_rev_lut_ptr^[n2]] := b_2 + b_3;
+      x^[bit_rev_lut_ptr^[n3]] := b_2 - b_3;
+
+      b_0 := sf2^[n4] + sf2^[n6];
+      b_2 := sf2^[n4] - sf2^[n6];
+      b_1 := sf2^[n5] * 2;
+      b_3 := sf2^[n7] * 2;
+
+      x^[bit_rev_lut_ptr^[n4]] := b_0 + b_1;
+      x^[bit_rev_lut_ptr^[n5]] := b_0 - b_1;
+      x^[bit_rev_lut_ptr^[n6]] := b_2 + b_3;
+      x^[bit_rev_lut_ptr^[n7]] := b_2 - b_3;
+
+      inc(sf2, 8);
+      inc(coef_index, 8);
+      inc(bit_rev_lut_ptr, 8);
+    until (coef_index >= _length);
+  end
+
+  (*______________________________________________
+   *
+   * Special cases
+   *______________________________________________
+   *)
+
+  // 4-point IFFT
+  else if _nbr_bits = 2 then
+  begin
+    b_0 := f^[0] + f [n2];
+    b_2 := f^[0] - f [n2];
+
+    x^[0] := b_0 + f [n1] * 2;
+    x^[n2] := b_0 - f [n1] * 2;
+    x^[n1] := b_2 + f [n3] * 2;
+    x^[n3] := b_2 - f [n3] * 2;
+  end
+
+  // 2-point IFFT
+  else if _nbr_bits = 1 then
+  begin
+    x^[0] := f^[0] + f^[n1];
+    x^[n1] := f^[0] - f^[n1];
+  end
+
+  // 1-point IFFT
+  else
+    x^[0] := f^[0];
+end;
+
+(*==========================================================================*/
+/*      Name: rescale                                                       */
+/*      Description: Scale an array by divide each element by its length.   */
+/*                   This function should be called after FFT + IFFT.       */
+/*      Input/Output parameters:                                            */
+/*        - x: pointer on array to rescale (time or frequency).             */
+/*==========================================================================*)
+procedure TFFTReal.rescale(x: pflt_array);
+var
+   mul  : flt_t;
+   i    : longint;
+begin
+  mul := 1.0 / _length;
+  i := _length - 1;
+
+  repeat
+    x^[i] := x^[i] * mul;
+    dec(i);
+  until (i < 0);
+end;
+
+end.
diff --git a/demos/spectrum/fftreal/fftreal.pro b/demos/spectrum/fftreal/fftreal.pro
new file mode 100644
index 0000000..786a962
--- /dev/null
+++ b/demos/spectrum/fftreal/fftreal.pro
@@ -0,0 +1,41 @@
+TEMPLATE = lib
+TARGET   = fftreal
+
+# FFTReal
+HEADERS  += Array.h \
+            Array.hpp \
+            DynArray.h \
+            DynArray.hpp \
+            FFTRealFixLen.h \
+            FFTRealFixLen.hpp \
+            FFTRealFixLenParam.h \
+            FFTRealPassDirect.h \
+            FFTRealPassDirect.hpp \
+            FFTRealPassInverse.h \
+            FFTRealPassInverse.hpp \
+            FFTRealSelect.h \
+            FFTRealSelect.hpp \
+            FFTRealUseTrigo.h \
+            FFTRealUseTrigo.hpp \
+            OscSinCos.h \
+            OscSinCos.hpp \
+            def.h
+	    
+# Wrapper used to export the required instantiation of the FFTRealFixLen template
+HEADERS  += fftreal_wrapper.h
+SOURCES  += fftreal_wrapper.cpp
+
+DEFINES  += FFTREAL_LIBRARY
+
+symbian {
+    # Provide unique ID for the generated binary, required by Symbian OS
+    TARGET.UID3 = 0xA000E3FB
+} else {
+    macx {
+        CONFIG += lib_bundle
+    } else {
+        DESTDIR = ../bin
+    }
+} 
+
+
diff --git a/demos/spectrum/fftreal/fftreal_wrapper.cpp b/demos/spectrum/fftreal/fftreal_wrapper.cpp
new file mode 100644
index 0000000..50ab36d
--- /dev/null
+++ b/demos/spectrum/fftreal/fftreal_wrapper.cpp
@@ -0,0 +1,54 @@
+/***************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** This program is free software: you can redistribute it and/or modify
+** it under the terms of the GNU Lesser General Public License as
+** published by the Free Software Foundation, either version 2.1. This
+** program is distributed in the hope that it will be useful, but WITHOUT
+** ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+** FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+** for more details. You should have received a copy of the GNU General
+** Public License along with this program. If not, see
+** <http://www.gnu.org/licenses/>.
+**
+***************************************************************************/
+
+#include "fftreal_wrapper.h"
+
+// FFTReal code generates quite a lot of 'unused parameter' compiler warnings,
+// which we suppress here in order to get a clean build output.
+#if defined Q_CC_MSVC
+#    pragma warning(disable:4100)
+#elif defined Q_CC_GNU
+#    pragma GCC diagnostic ignored "-Wunused-parameter"
+#elif defined Q_CC_MWERKS
+#    pragma warning off (10182)
+#endif
+
+#include "FFTRealFixLen.h"
+
+class FFTRealWrapperPrivate {
+public:
+    FFTRealFixLen<FFTLengthPowerOfTwo> m_fft;
+};
+
+
+FFTRealWrapper::FFTRealWrapper()
+    :   m_private(new FFTRealWrapperPrivate)
+{
+
+}
+
+FFTRealWrapper::~FFTRealWrapper()
+{
+    delete m_private;
+}
+
+void FFTRealWrapper::calculateFFT(DataType in[], const DataType out[])
+{
+    m_private->m_fft.do_fft(in, out);
+}
diff --git a/demos/spectrum/fftreal/fftreal_wrapper.h b/demos/spectrum/fftreal/fftreal_wrapper.h
new file mode 100644
index 0000000..48d614e
--- /dev/null
+++ b/demos/spectrum/fftreal/fftreal_wrapper.h
@@ -0,0 +1,63 @@
+/***************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** This program is free software: you can redistribute it and/or modify
+** it under the terms of the GNU Lesser General Public License as
+** published by the Free Software Foundation, either version 2.1. This
+** program is distributed in the hope that it will be useful, but WITHOUT
+** ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+** FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+** for more details. You should have received a copy of the GNU General
+** Public License along with this program. If not, see
+** <http://www.gnu.org/licenses/>.
+**
+***************************************************************************/
+
+#ifndef FFTREAL_WRAPPER_H
+#define FFTREAL_WRAPPER_H
+
+#include <QtCore/QtGlobal>
+
+#if defined(FFTREAL_LIBRARY)
+#  define FFTREAL_EXPORT Q_DECL_EXPORT
+#else
+#  define FFTREAL_EXPORT Q_DECL_IMPORT
+#endif
+
+class FFTRealWrapperPrivate;
+
+// Each pass of the FFT processes 2^X samples, where X is the
+// number below.
+static const int FFTLengthPowerOfTwo = 12;
+
+/**
+ * Wrapper around the FFTRealFixLen template provided by the FFTReal
+ * library
+ *
+ * This class instantiates a single instance of FFTRealFixLen, using
+ * FFTLengthPowerOfTwo as the template parameter.  It then exposes
+ * FFTRealFixLen<FFTLengthPowerOfTwo>::do_fft via the calculateFFT
+ * function, thereby allowing an application to dynamically link
+ * against the FFTReal implementation.
+ *
+ * See http://ldesoras.free.fr/prod.html
+ */
+class FFTREAL_EXPORT FFTRealWrapper
+{
+public:
+    FFTRealWrapper();
+    ~FFTRealWrapper();
+
+    typedef float DataType;
+    void calculateFFT(DataType in[], const DataType out[]);
+
+private:
+    FFTRealWrapperPrivate*  m_private;
+};
+
+#endif // FFTREAL_WRAPPER_H
+
diff --git a/demos/spectrum/fftreal/license.txt b/demos/spectrum/fftreal/license.txt
new file mode 100644
index 0000000..918fe68
--- /dev/null
+++ b/demos/spectrum/fftreal/license.txt
@@ -0,0 +1,459 @@
+		  GNU LESSER GENERAL PUBLIC LICENSE
+		       Version 2.1, February 1999
+
+ Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+     59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+[This is the first released version of the Lesser GPL.  It also counts
+ as the successor of the GNU Library Public License, version 2, hence
+ the version number 2.1.]
+
+			    Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+Licenses are intended to guarantee your freedom to share and change
+free software--to make sure the software is free for all its users.
+
+  This license, the Lesser General Public License, applies to some
+specially designated software packages--typically libraries--of the
+Free Software Foundation and other authors who decide to use it.  You
+can use it too, but we suggest you first think carefully about whether
+this license or the ordinary General Public License is the better
+strategy to use in any particular case, based on the explanations below.
+
+  When we speak of free software, we are referring to freedom of use,
+not price.  Our General Public Licenses are designed to make sure that
+you have the freedom to distribute copies of free software (and charge
+for this service if you wish); that you receive source code or can get
+it if you want it; that you can change the software and use pieces of
+it in new free programs; and that you are informed that you can do
+these things.
+
+  To protect your rights, we need to make restrictions that forbid
+distributors to deny you these rights or to ask you to surrender these
+rights.  These restrictions translate to certain responsibilities for
+you if you distribute copies of the library or if you modify it.
+
+  For example, if you distribute copies of the library, whether gratis
+or for a fee, you must give the recipients all the rights that we gave
+you.  You must make sure that they, too, receive or can get the source
+code.  If you link other code with the library, you must provide
+complete object files to the recipients, so that they can relink them
+with the library after making changes to the library and recompiling
+it.  And you must show them these terms so they know their rights.
+
+  We protect your rights with a two-step method: (1) we copyright the
+library, and (2) we offer you this license, which gives you legal
+permission to copy, distribute and/or modify the library.
+
+  To protect each distributor, we want to make it very clear that
+there is no warranty for the free library.  Also, if the library is
+modified by someone else and passed on, the recipients should know
+that what they have is not the original version, so that the original
+author's reputation will not be affected by problems that might be
+introduced by others.
+
+  Finally, software patents pose a constant threat to the existence of
+any free program.  We wish to make sure that a company cannot
+effectively restrict the users of a free program by obtaining a
+restrictive license from a patent holder.  Therefore, we insist that
+any patent license obtained for a version of the library must be
+consistent with the full freedom of use specified in this license.
+
+  Most GNU software, including some libraries, is covered by the
+ordinary GNU General Public License.  This license, the GNU Lesser
+General Public License, applies to certain designated libraries, and
+is quite different from the ordinary General Public License.  We use
+this license for certain libraries in order to permit linking those
+libraries into non-free programs.
+
+  When a program is linked with a library, whether statically or using
+a shared library, the combination of the two is legally speaking a
+combined work, a derivative of the original library.  The ordinary
+General Public License therefore permits such linking only if the
+entire combination fits its criteria of freedom.  The Lesser General
+Public License permits more lax criteria for linking other code with
+the library.
+
+  We call this license the "Lesser" General Public License because it
+does Less to protect the user's freedom than the ordinary General
+Public License.  It also provides other free software developers Less
+of an advantage over competing non-free programs.  These disadvantages
+are the reason we use the ordinary General Public License for many
+libraries.  However, the Lesser license provides advantages in certain
+special circumstances.
+
+  For example, on rare occasions, there may be a special need to
+encourage the widest possible use of a certain library, so that it becomes
+a de-facto standard.  To achieve this, non-free programs must be
+allowed to use the library.  A more frequent case is that a free
+library does the same job as widely used non-free libraries.  In this
+case, there is little to gain by limiting the free library to free
+software only, so we use the Lesser General Public License.
+
+  In other cases, permission to use a particular library in non-free
+programs enables a greater number of people to use a large body of
+free software.  For example, permission to use the GNU C Library in
+non-free programs enables many more people to use the whole GNU
+operating system, as well as its variant, the GNU/Linux operating
+system.
+
+  Although the Lesser General Public License is Less protective of the
+users' freedom, it does ensure that the user of a program that is
+linked with the Library has the freedom and the wherewithal to run
+that program using a modified version of the Library.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.  Pay close attention to the difference between a
+"work based on the library" and a "work that uses the library".  The
+former contains code derived from the library, whereas the latter must
+be combined with the library in order to run.
+
+		  GNU LESSER GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License Agreement applies to any software library or other
+program which contains a notice placed by the copyright holder or
+other authorized party saying it may be distributed under the terms of
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+Each licensee is addressed as "you".
+
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+(which use some of those functions and data) to form executables.
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+
+  "Source code" for a work means the preferred form of the work for
+making modifications to it.  For a library, complete source code means
+all the source code for all modules it contains, plus any associated
+interface definition files, plus the scripts used to control compilation
+and installation of the library.
+
+  Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running a program using the Library is not restricted, and output from
+such a program is covered only if its contents constitute a work based
+on the Library (independent of the use of the Library in a tool for
+writing it).  Whether that is true depends on what the Library does
+and what the program that uses the Library does.
+  
+  1. You may copy and distribute verbatim copies of the Library's
+complete source code as you receive it, in any medium, provided that
+you conspicuously and appropriately publish on each copy an
+appropriate copyright notice and disclaimer of warranty; keep intact
+all the notices that refer to this License and to the absence of any
+warranty; and distribute a copy of this License along with the
+Library.
+
+  You may charge a fee for the physical act of transferring a copy,
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+    c) You must cause the whole of the work to be licensed at no
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+
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+    a purpose that is entirely well-defined independent of the
+    application.  Therefore, Subsection 2d requires that any
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diff --git a/demos/spectrum/fftreal/readme.txt b/demos/spectrum/fftreal/readme.txt
new file mode 100644
index 0000000..0c5ce16
--- /dev/null
+++ b/demos/spectrum/fftreal/readme.txt
@@ -0,0 +1,242 @@
+==============================================================================
+
+        FFTReal
+        Version 2.00, 2005/10/18
+
+        Fourier transformation (FFT, IFFT) library specialised for real data
+        Portable ISO C++
+
+        (c) Laurent de Soras <laurent.de.soras@club-internet.fr>
+        Object Pascal port (c) Frederic Vanmol <frederic@fruityloops.com>
+
+==============================================================================
+
+
+
+1. Legal
+--------
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+Check the file license.txt to get full information about the license.
+
+
+
+2. Content
+----------
+
+FFTReal is a library to compute Discrete Fourier Transforms (DFT) with the
+FFT algorithm (Fast Fourier Transform) on arrays of real numbers. It can
+also compute the inverse transform.
+
+You should find in this package a lot of files ; some of them are of interest:
+- readme.txt: you are reading it
+- FFTReal.h: FFT, length fixed at run-time
+- FFTRealFixLen.h: FFT, length fixed at compile-time
+- FFTReal.pas: Pascal implementation (working but not up-to-date)
+- stopwatch directory
+
+
+
+3. Using FFTReal
+----------------
+
+Important - if you were using older versions of FFTReal (up to 1.03), some
+things have changed. FFTReal is now a template. Therefore use FFTReal<float>
+or FFTReal<double> in your code depending on the application datatype. The
+flt_t typedef has been removed.
+
+You have two ways to use FFTReal. In the first way, the FFT has its length
+fixed at run-time, when the object is instanciated. It means that you have
+not to know the length when you write the code. This is the usual way of
+proceeding.
+
+
+3.1 FFTReal - Length fixed at run-time
+--------------------------------------
+
+Just instanciate one time a FFTReal object. Specify the data type you want
+as template parameter (only floating point: float, double, long double or
+custom type). The constructor precompute a lot of things, so it may be a bit
+long. The parameter is the number of points used for the next FFTs. It must
+be a power of 2:
+
+   #include "FFTReal.h"
+   ...
+   long len = 1024;
+   ...
+   FFTReal <float> fft_object (len);   // 1024-point FFT object constructed.
+
+Then you can use this object to compute as many FFTs and IFFTs as you want.
+They will be computed very quickly because a lot of work has been done in the
+object construction.
+
+   float x [1024];
+   float f [1024];
+
+   ...
+   fft_object.do_fft (f, x);     // x (real) --FFT---> f (complex)
+   ...
+   fft_object.do_ifft (f, x);    // f (complex) --IFFT--> x (real)
+   fft_object.rescale (x);       // Post-scaling should be done after FFT+IFFT
+   ...
+
+x [] and f [] are floating point number arrays. x [] is the real number
+sequence which we want to compute the FFT. f [] is the result, in the
+"frequency" domain. f has the same number of elements as x [], but f []
+elements are complex numbers. The routine uses some FFT properties to
+optimize memory and to reduce calculations: the transformaton of a real
+number sequence is a conjugate complex number sequence: F [k] = F [-k]*.
+
+
+3.2 FFTRealFixLen - Length fixed at compile-time
+------------------------------------------------
+
+This class is significantly faster than the previous one, giving a speed
+gain between 50 and 100 %. The template parameter is the base-2 logarithm of
+the FFT length. The datatype is float; it can be changed by modifying the
+DataType typedef in FFTRealFixLenParam.h. As FFTReal class, it supports
+only floating-point types or equivalent.
+
+To instanciate the object, just proceed as below:
+
+   #include "FFTRealFixLen.h"
+   ...
+   FFTRealFixLen <10> fft_object; // 1024-point (2^10) FFT object constructed.
+
+Use is similar as the one of FFTReal.
+
+
+3.3 Data organisation
+---------------------
+
+Mathematically speaking, the formulas below show what does FFTReal:
+
+do_fft() : f(k) = sum (p = 0, N-1, x(p) * exp (+j*2*pi*k*p/N))
+do_ifft(): x(k) = sum (p = 0, N-1, f(p) * exp (-j*2*pi*k*p/N))
+
+Where j is the square root of -1. The formulas differ only by the sign of
+the exponential. When the sign is positive, the transform is called positive.
+Common formulas for Fourier transform are negative for the direct tranform and
+positive for the inverse one.
+
+However in these formulas, f is an array of complex numbers and doesn't
+correspound exactly to the f[] array taken as function parameter. The
+following table shows how the f[] sequence is mapped onto the usable FFT
+coefficients (called bins):
+
+   FFTReal output | Positive FFT equiv.   | Negative FFT equiv.
+   ---------------+-----------------------+-----------------------
+   f [0]          | Real (bin 0)          | Real (bin 0)
+   f [...]        | Real (bin ...)        | Real (bin ...)
+   f [length/2]   | Real (bin length/2)   | Real (bin length/2)
+   f [length/2+1] | Imag (bin 1)          | -Imag (bin 1)
+   f [...]        | Imag (bin ...)        | -Imag (bin ...)
+   f [length-1]   | Imag (bin length/2-1) | -Imag (bin length/2-1)
+
+And FFT bins are distributed in f [] as above:
+
+               |                | Positive FFT    | Negative FFT
+   Bin         | Real part      | imaginary part  | imaginary part
+   ------------+----------------+-----------------+---------------
+   0           | f [0]          | 0               | 0
+   1           | f [1]          | f [length/2+1]  | -f [length/2+1]
+   ...         | f [...],       | f [...]         | -f [...]
+   length/2-1  | f [length/2-1] | f [length-1]    | -f [length-1]
+   length/2    | f [length/2]   | 0               | 0
+   length/2+1  | f [length/2-1] | -f [length-1]   | f [length-1]
+   ...         | f [...]        | -f [...]        | f [...]
+   length-1    | f [1]          | -f [length/2+1] | f [length/2+1]
+
+f [] coefficients have the same layout for FFT and IFFT functions. You may
+notice that scaling must be done if you want to retrieve x after FFT and IFFT.
+Actually, IFFT (FFT (x)) = x * length(x). This is a not a problem because
+most of the applications don't care about absolute values. Thus, the operation
+requires less calculation. If you want to use the FFT and IFFT to transform a
+signal, you have to apply post- (or pre-) processing yourself. Multiplying
+or dividing floating point numbers by a power of 2 doesn't generate extra
+computation noise.
+
+
+
+4. Compilation and testing
+--------------------------
+
+Drop the following files into your project or makefile:
+
+Array.*
+def.h
+DynArray.*
+FFTReal*.cpp
+FFTReal*.h*
+OscSinCos.*
+
+Other files are for testing purpose only, do not include them if you just need
+to use the library ; they are not needed to use FFTReal in your own programs.
+
+FFTReal may be compiled in two versions: release and debug. Debug version
+has checks that could slow down the code. Define NDEBUG to set the Release
+mode. For example, the command line to compile the test bench on GCC would
+look like:
+
+Debug mode:
+g++ -Wall -o fftreal_debug.exe *.cpp stopwatch/*.cpp
+
+Release mode:
+g++ -Wall -o fftreal_release.exe -DNDEBUG -O3 *.cpp stopwatch/*.cpp
+
+It may be tricky to compile the test bench because the speed tests use the
+stopwatch sub-library, which is not that cross-platform. If you encounter
+any problem that you cannot easily fix while compiling it, edit the file
+test_settings.h and un-define the speed test macro. Remove the stopwatch
+directory from your source file list, too.
+
+If it's not done by default, you should activate the exception handling
+of your compiler to get the class memory-leak-safe. Thus, when a memory
+allocation fails (in the constructor), an exception is thrown and the entire
+object is safely destructed. It reduces the permanent error checking overhead
+in the client code. Also, the test bench requires Run-Time Type Information
+(RTTI) to be enabled in order to display the names of the tested classes -
+sometimes mangled, depending on the compiler.
+
+The test bench may take a long time to compile, especially in Release mode,
+because a lot of recursive templates are instanciated.
+
+
+
+5. History
+----------
+
+v2.00 (2005.10.18)
+- Turned FFTReal class into template (data type as parameter)
+- Added FFTRealFixLen
+- Trigonometric tables are size-limited in order to preserve cache memory;
+over a given size, sin/cos functions are computed on the fly.
+- Better test bench for accuracy and speed
+
+v1.03 (2001.06.15)
+- Thanks to Frederic Vanmol for the Pascal port (works with Delphi).
+- Documentation improvement
+
+v1.02 (2001.03.25)
+- sqrt() is now precomputed when the object FFTReal is constructed, resulting
+in speed impovement for small size FFT.
+
+v1.01 (2000)
+- Small modifications, I don't remember what.
+
+v1.00 (1999.08.14)
+- First version released
+
diff --git a/demos/spectrum/fftreal/stopwatch/ClockCycleCounter.cpp b/demos/spectrum/fftreal/stopwatch/ClockCycleCounter.cpp
new file mode 100644
index 0000000..fe1d424
--- /dev/null
+++ b/demos/spectrum/fftreal/stopwatch/ClockCycleCounter.cpp
@@ -0,0 +1,285 @@
+/*****************************************************************************
+
+        ClockCycleCounter.cpp
+        Copyright (c) 2003 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (_MSC_VER)
+	#pragma warning (1 : 4130) // "'operator' : logical operation on address of string constant"
+	#pragma warning (1 : 4223) // "nonstandard extension used : non-lvalue array converted to pointer"
+	#pragma warning (1 : 4705) // "statement has no effect"
+	#pragma warning (1 : 4706) // "assignment within conditional expression"
+	#pragma warning (4 : 4786) // "identifier was truncated to '255' characters in the debug information"
+	#pragma warning (4 : 4800) // "forcing value to bool 'true' or 'false' (performance warning)"
+	#pragma warning (4 : 4355) // "'this' : used in base member initializer list"
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"ClockCycleCounter.h"
+
+#include	<cassert>
+
+
+
+namespace stopwatch
+{
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*
+==============================================================================
+Name: ctor
+Description:
+	The first object constructed initialise global data. This first
+	construction may be a bit slow.
+Throws: Nothing
+==============================================================================
+*/
+
+ClockCycleCounter::ClockCycleCounter ()
+:	_start_time (0)
+,	_state (0)
+,	_best_score (-1)
+{
+	if (! _init_flag)
+	{
+		// Should be executed in this order
+		compute_clk_mul ();
+		compute_measure_time_total ();
+		compute_measure_time_lap ();
+
+		// Restores object state
+		_start_time = 0;
+		_state      = 0;
+		_best_score = -1;
+
+		_init_flag = true;
+	}
+}
+
+
+
+/*
+==============================================================================
+Name: get_time_total
+Description:
+	Gives the time elapsed between the latest stop_lap() and start() calls.
+Returns:
+	The duration, in clock cycles.
+Throws: Nothing
+==============================================================================
+*/
+
+Int64	ClockCycleCounter::get_time_total () const
+{
+	const Int64		duration = _state - _start_time;
+	assert (duration >= 0);
+
+	const Int64		t = max (
+		duration - _measure_time_total,
+		static_cast <Int64> (0)
+	);
+
+	return (t * _clk_mul);
+}
+
+
+
+/*
+==============================================================================
+Name: get_time_best_lap
+Description:
+	Gives the smallest time between two consecutive stop_lap() or between
+	the stop_lap() and start(). The value is reset by a call to start().
+	Call this function only after a stop_lap().
+	The time is amputed from the duration of the stop_lap() call itself.
+Returns:
+	The smallest duration, in clock cycles.
+Throws: Nothing
+==============================================================================
+*/
+
+Int64	ClockCycleCounter::get_time_best_lap () const
+{
+	assert (_best_score >= 0);
+
+	const Int64		t1 = max (
+		_best_score - _measure_time_lap,
+		static_cast <Int64> (0)
+	);
+	const Int64		t = min (t1, get_time_total ());
+
+	return (t * _clk_mul);
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+#if defined (__MACOS__)
+
+static inline double	stopwatch_ClockCycleCounter_get_time_s ()
+{
+	const Nanoseconds	ns = AbsoluteToNanoseconds (UpTime ());
+
+	return (ns.hi * 4294967296e-9 + ns.lo * 1e-9);
+}
+
+#endif	// __MACOS__
+
+
+
+/*
+==============================================================================
+Name: compute_clk_mul
+Description:
+	This function, only for PowerPC/MacOS computers, computes the multiplier
+	required to deduce clock cycles from the internal counter.
+Throws: Nothing
+==============================================================================
+*/
+
+void	ClockCycleCounter::compute_clk_mul ()
+{
+	assert (! _init_flag);
+
+#if defined (__MACOS__)
+
+	long				clk_speed_mhz = CurrentProcessorSpeed ();
+	const Int64		clk_speed =
+		static_cast <Int64> (clk_speed_mhz) * (1000L*1000L);
+
+	const double	start_time_s = stopwatch_ClockCycleCounter_get_time_s ();
+	start ();
+
+	const double	duration = 0.01;	// Seconds
+	while (stopwatch_ClockCycleCounter_get_time_s () - start_time_s < duration)
+	{
+		continue;
+	}
+
+	const double	stop_time_s = stopwatch_ClockCycleCounter_get_time_s ();
+	stop ();
+
+	const double	diff_time_s = stop_time_s - start_time_s;
+	const double	nbr_cycles = diff_time_s * static_cast <double> (clk_speed);
+
+	const Int64		diff_time_c = _state - _start_time;
+	const double	clk_mul = nbr_cycles / static_cast <double> (diff_time_c);
+
+	_clk_mul = round_int (clk_mul);
+
+#endif	// __MACOS__
+}
+
+
+
+void	ClockCycleCounter::compute_measure_time_total ()
+{
+	start ();
+	spend_time ();
+
+	Int64				best_result = 0x7FFFFFFFL;	// Should be enough
+	long				nbr_tests = 100;
+	for (long cnt = 0; cnt < nbr_tests; ++cnt)
+	{
+		start ();
+		stop_lap ();
+		const Int64		duration = _state - _start_time;
+		best_result = min (best_result, duration);
+	}
+
+	_measure_time_total = best_result;
+}
+
+
+
+/*
+==============================================================================
+Name: compute_measure_time_lap
+Description:
+	Computes the duration of one stop_lap() call and store it. It will be used
+	later to get the real duration of the measured operation (by substracting
+	the measurement duration).
+Throws: Nothing
+==============================================================================
+*/
+
+void	ClockCycleCounter::compute_measure_time_lap ()
+{
+	start ();
+	spend_time ();
+
+	long				nbr_tests = 10;
+	for (long cnt = 0; cnt < nbr_tests; ++cnt)
+	{
+		stop_lap ();
+		stop_lap ();
+		stop_lap ();
+		stop_lap ();
+	}
+
+	_measure_time_lap = _best_score;
+}
+
+
+
+void	ClockCycleCounter::spend_time ()
+{
+	const Int64		nbr_clocks = 500;	// Number of clock cycles to spend
+
+	const Int64		start = read_clock_counter ();
+	Int64				current;
+
+	do
+	{
+		current = read_clock_counter ();
+	}
+	while ((current - start) * _clk_mul < nbr_clocks);
+}
+
+
+
+Int64	ClockCycleCounter::_measure_time_total = 0;
+Int64	ClockCycleCounter::_measure_time_lap = 0;
+int	ClockCycleCounter::_clk_mul = 1;
+bool	ClockCycleCounter::_init_flag = false;
+
+
+}	// namespace stopwatch
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/stopwatch/ClockCycleCounter.h b/demos/spectrum/fftreal/stopwatch/ClockCycleCounter.h
new file mode 100644
index 0000000..ba7a99a
--- /dev/null
+++ b/demos/spectrum/fftreal/stopwatch/ClockCycleCounter.h
@@ -0,0 +1,124 @@
+/*****************************************************************************
+
+        ClockCycleCounter.h
+        Copyright (c) 2003 Laurent de Soras
+
+Instrumentation class, for accurate time interval measurement. You may have
+to modify the implementation to adapt it to your system and/or compiler.
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (stopwatch_ClockCycleCounter_HEADER_INCLUDED)
+#define	stopwatch_ClockCycleCounter_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"def.h"
+#include	"Int64.h"
+
+
+
+namespace stopwatch
+{
+
+
+
+class ClockCycleCounter
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+						ClockCycleCounter ();
+
+	stopwatch_FORCEINLINE void
+						start ();
+	stopwatch_FORCEINLINE void
+						stop_lap ();
+	Int64				get_time_total () const;
+	Int64				get_time_best_lap () const;
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+	void				compute_clk_mul ();
+	void				compute_measure_time_total ();
+	void				compute_measure_time_lap ();
+
+	static void		spend_time ();
+	static stopwatch_FORCEINLINE Int64
+						read_clock_counter ();
+
+	Int64				_start_time;
+	Int64				_state;
+	Int64				_best_score;
+
+	static Int64	_measure_time_total;
+	static Int64	_measure_time_lap;
+	static int		_clk_mul;
+	static bool		_init_flag;
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						ClockCycleCounter (const ClockCycleCounter &other);
+	ClockCycleCounter &
+						operator = (const ClockCycleCounter &other);
+	bool				operator == (const ClockCycleCounter &other);
+	bool				operator != (const ClockCycleCounter &other);
+
+};	// class ClockCycleCounter
+
+
+
+}	// namespace stopwatch
+
+
+
+#include	"ClockCycleCounter.hpp"
+
+
+
+#endif	// stopwatch_ClockCycleCounter_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/stopwatch/ClockCycleCounter.hpp b/demos/spectrum/fftreal/stopwatch/ClockCycleCounter.hpp
new file mode 100644
index 0000000..fbd511e
--- /dev/null
+++ b/demos/spectrum/fftreal/stopwatch/ClockCycleCounter.hpp
@@ -0,0 +1,150 @@
+/*****************************************************************************
+
+        ClockCycleCounter.hpp
+        Copyright (c) 2003 Laurent de Soras
+
+Please complete the definitions according to your compiler/architecture.
+It's not a big deal if it's not possible to get the clock count...
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (stopwatch_ClockCycleCounter_CURRENT_CODEHEADER)
+	#error Recursive inclusion of ClockCycleCounter code header.
+#endif
+#define	stopwatch_ClockCycleCounter_CURRENT_CODEHEADER
+
+#if ! defined (stopwatch_ClockCycleCounter_CODEHEADER_INCLUDED)
+#define	stopwatch_ClockCycleCounter_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"fnc.h"
+
+#include	<climits>
+
+
+
+namespace stopwatch
+{
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*
+==============================================================================
+Name: start
+Description:
+	Starts the counter.
+Throws: Nothing
+==============================================================================
+*/
+
+void	ClockCycleCounter::start ()
+{
+	_best_score = (static_cast <Int64> (1) << (sizeof (Int64) * CHAR_BIT - 2));
+	const Int64		start_clock = read_clock_counter ();
+	_start_time = start_clock;
+	_state = start_clock - _best_score;
+}
+
+
+
+/*
+==============================================================================
+Name: stop_lap
+Description:
+	Captures the current time and updates the smallest duration between two
+	consecutive calls to stop_lap() or the latest start().
+	start() must have been called at least once before calling this function.
+Throws: Nothing
+==============================================================================
+*/
+
+void	ClockCycleCounter::stop_lap ()
+{
+	const Int64		end_clock = read_clock_counter ();
+	_best_score = min (end_clock - _state, _best_score);
+	_state = end_clock;
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+Int64	ClockCycleCounter::read_clock_counter ()
+{
+	register Int64		clock_cnt;
+
+#if defined (_MSC_VER)
+
+	__asm
+	{
+		lea				edi, clock_cnt
+		rdtsc
+		mov				[edi    ], eax
+		mov				[edi + 4], edx
+	}
+
+#elif defined (__GNUC__) && defined (__i386__)
+
+	__asm__ __volatile__ ("rdtsc" : "=A" (clock_cnt));
+
+#elif (__MWERKS__) && defined (__POWERPC__) 
+	
+	asm
+	{
+	loop:
+		mftbu			clock_cnt@hiword
+		mftb			clock_cnt@loword
+		mftbu			r5
+		cmpw			clock_cnt@hiword,r5
+		bne loop
+	}
+	
+#endif
+
+	return (clock_cnt);
+}
+
+
+
+}	// namespace stopwatch
+
+
+
+#endif	// stopwatch_ClockCycleCounter_CODEHEADER_INCLUDED
+
+#undef stopwatch_ClockCycleCounter_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/stopwatch/Int64.h b/demos/spectrum/fftreal/stopwatch/Int64.h
new file mode 100644
index 0000000..1e786e2
--- /dev/null
+++ b/demos/spectrum/fftreal/stopwatch/Int64.h
@@ -0,0 +1,71 @@
+/*****************************************************************************
+
+        Int64.h
+        Copyright (c) 2003 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (stopwatch_Int64_HEADER_INCLUDED)
+#define	stopwatch_Int64_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+namespace stopwatch
+{
+
+
+#if defined (_MSC_VER)
+
+	typedef	__int64	Int64;
+
+#elif defined (__MWERKS__) || defined (__GNUC__)
+
+	typedef	long long	Int64;
+
+#elif defined (__BEOS__)
+
+	typedef	int64	Int64;
+
+#else
+
+	#error No 64-bit integer type defined for this compiler !
+
+#endif
+
+
+}	// namespace stopwatch
+
+
+
+#endif	// stopwatch_Int64_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/stopwatch/StopWatch.cpp b/demos/spectrum/fftreal/stopwatch/StopWatch.cpp
new file mode 100644
index 0000000..7795d86
--- /dev/null
+++ b/demos/spectrum/fftreal/stopwatch/StopWatch.cpp
@@ -0,0 +1,101 @@
+/*****************************************************************************
+
+        StopWatch.cpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (_MSC_VER)
+	#pragma warning (1 : 4130) // "'operator' : logical operation on address of string constant"
+	#pragma warning (1 : 4223) // "nonstandard extension used : non-lvalue array converted to pointer"
+	#pragma warning (1 : 4705) // "statement has no effect"
+	#pragma warning (1 : 4706) // "assignment within conditional expression"
+	#pragma warning (4 : 4786) // "identifier was truncated to '255' characters in the debug information"
+	#pragma warning (4 : 4800) // "forcing value to bool 'true' or 'false' (performance warning)"
+	#pragma warning (4 : 4355) // "'this' : used in base member initializer list"
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"StopWatch.h"
+
+#include	<cassert>
+
+
+
+namespace stopwatch
+{
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+StopWatch::StopWatch ()
+:	_ccc ()
+,	_nbr_laps (0)
+{
+	// Nothing
+}
+
+
+
+double	StopWatch::get_time_total (Int64 nbr_op) const
+{
+	assert (_nbr_laps > 0);
+	assert (nbr_op > 0);
+
+	return (
+		  static_cast <double> (_ccc.get_time_total ())
+	   / (static_cast <double> (nbr_op) * static_cast <double> (_nbr_laps))
+	);
+}
+
+
+
+double	StopWatch::get_time_best_lap (Int64 nbr_op) const
+{
+	assert (nbr_op > 0);
+
+	return (
+		  static_cast <double> (_ccc.get_time_best_lap ())
+		/ static_cast <double> (nbr_op)
+	);
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+}	// namespace stopwatch
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/stopwatch/StopWatch.h b/demos/spectrum/fftreal/stopwatch/StopWatch.h
new file mode 100644
index 0000000..9cc47e5
--- /dev/null
+++ b/demos/spectrum/fftreal/stopwatch/StopWatch.h
@@ -0,0 +1,110 @@
+/*****************************************************************************
+
+        StopWatch.h
+        Copyright (c) 2005 Laurent de Soras
+
+Utility class based on ClockCycleCounter to measure the unit time of a
+repeated operation.
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (stopwatch_StopWatch_HEADER_INCLUDED)
+#define	stopwatch_StopWatch_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"ClockCycleCounter.h"
+
+
+
+namespace stopwatch
+{
+
+
+
+class StopWatch
+{
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+public:
+
+						StopWatch ();
+
+	stopwatch_FORCEINLINE void
+						start ();
+	stopwatch_FORCEINLINE void
+						stop_lap ();
+
+	double			get_time_total (Int64 nbr_op) const;
+	double			get_time_best_lap (Int64 nbr_op) const;
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+protected:
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+	ClockCycleCounter
+						_ccc;
+	Int64				_nbr_laps;
+
+
+
+/*\\\ FORBIDDEN MEMBER FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+private:
+
+						StopWatch (const StopWatch &other);
+	StopWatch &		operator = (const StopWatch &other);
+	bool				operator == (const StopWatch &other);
+	bool				operator != (const StopWatch &other);
+
+};	// class StopWatch
+
+
+
+}	// namespace stopwatch
+
+
+
+#include	"StopWatch.hpp"
+
+
+
+#endif	// stopwatch_StopWatch_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/stopwatch/StopWatch.hpp b/demos/spectrum/fftreal/stopwatch/StopWatch.hpp
new file mode 100644
index 0000000..74482a7
--- /dev/null
+++ b/demos/spectrum/fftreal/stopwatch/StopWatch.hpp
@@ -0,0 +1,83 @@
+/*****************************************************************************
+
+        StopWatch.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (stopwatch_StopWatch_CURRENT_CODEHEADER)
+	#error Recursive inclusion of StopWatch code header.
+#endif
+#define	stopwatch_StopWatch_CURRENT_CODEHEADER
+
+#if ! defined (stopwatch_StopWatch_CODEHEADER_INCLUDED)
+#define	stopwatch_StopWatch_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+namespace stopwatch
+{
+
+
+
+/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+void	StopWatch::start ()
+{
+	_nbr_laps = 0;
+	_ccc.start ();
+}
+
+
+
+void	StopWatch::stop_lap ()
+{
+	_ccc.stop_lap ();
+	++ _nbr_laps;
+}
+
+
+
+/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+}	// namespace stopwatch
+
+
+
+#endif	// stopwatch_StopWatch_CODEHEADER_INCLUDED
+
+#undef stopwatch_StopWatch_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/stopwatch/def.h b/demos/spectrum/fftreal/stopwatch/def.h
new file mode 100644
index 0000000..81ee6aa
--- /dev/null
+++ b/demos/spectrum/fftreal/stopwatch/def.h
@@ -0,0 +1,65 @@
+/*****************************************************************************
+
+        def.h
+        Copyright (c) 2003 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (stopwatch_def_HEADER_INCLUDED)
+#define	stopwatch_def_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+namespace stopwatch
+{
+
+
+
+#if defined (_MSC_VER)
+
+	#define	stopwatch_FORCEINLINE	__forceinline
+
+#else
+
+	#define	stopwatch_FORCEINLINE	inline
+
+#endif
+
+
+
+}	// namespace stopwatch
+
+
+
+#endif	// stopwatch_def_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/stopwatch/fnc.h b/demos/spectrum/fftreal/stopwatch/fnc.h
new file mode 100644
index 0000000..0554535
--- /dev/null
+++ b/demos/spectrum/fftreal/stopwatch/fnc.h
@@ -0,0 +1,67 @@
+/*****************************************************************************
+
+        fnc.h
+        Copyright (c) 2003 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (stopwatch_fnc_HEADER_INCLUDED)
+#define	stopwatch_fnc_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+namespace stopwatch
+{
+
+
+
+template <typename T>
+inline T	min (T a, T b);
+
+template <typename T>
+inline T	max (T a, T b);
+
+inline int	round_int (double x);
+
+
+
+}	// namespace rsp
+
+
+
+#include	"fnc.hpp"
+
+
+
+#endif	// stopwatch_fnc_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/stopwatch/fnc.hpp b/demos/spectrum/fftreal/stopwatch/fnc.hpp
new file mode 100644
index 0000000..0ab5949
--- /dev/null
+++ b/demos/spectrum/fftreal/stopwatch/fnc.hpp
@@ -0,0 +1,85 @@
+/*****************************************************************************
+
+        fnc.hpp
+        Copyright (c) 2003 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (stopwatch_fnc_CURRENT_CODEHEADER)
+	#error Recursive inclusion of fnc code header.
+#endif
+#define	stopwatch_fnc_CURRENT_CODEHEADER
+
+#if ! defined (stopwatch_fnc_CODEHEADER_INCLUDED)
+#define	stopwatch_fnc_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	<cassert>
+#include	<cmath>
+
+namespace std {}
+
+
+
+namespace stopwatch
+{
+
+
+
+template <typename T>
+inline T	min (T a, T b)
+{
+	return ((a < b) ? a : b);
+}
+
+
+
+template <typename T>
+inline T	max (T a, T b)
+{
+	return ((b < a) ? a : b);
+}
+
+
+
+int	round_int (double x)
+{
+	using namespace std;
+
+	return (static_cast <int> (floor (x + 0.5)));
+}
+
+
+
+}	// namespace stopwatch
+
+
+
+#endif	// stopwatch_fnc_CODEHEADER_INCLUDED
+
+#undef stopwatch_fnc_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/test.cpp b/demos/spectrum/fftreal/test.cpp
new file mode 100644
index 0000000..7b6ed2c
--- /dev/null
+++ b/demos/spectrum/fftreal/test.cpp
@@ -0,0 +1,267 @@
+/*****************************************************************************
+
+        test.cpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (_MSC_VER)
+	#pragma warning (4 : 4786) // "identifier was truncated to '255' characters in the debug information"
+	#pragma warning (4 : 4800) // "forcing value to bool 'true' or 'false' (performance warning)"
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+#include	"test_settings.h"
+#include	"TestHelperFixLen.h"
+#include	"TestHelperNormal.h"
+
+#if defined (_MSC_VER)
+#include	<crtdbg.h>
+#include	<new.h>
+#endif	// _MSC_VER
+
+#include	<new>
+
+#include	<cassert>
+#include	<cstdio>
+
+
+
+#define	TEST_
+
+
+/*\\\ FUNCTIONS \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+static int	TEST_perform_test_accuracy_all ();
+static int	TEST_perform_test_speed_all ();
+
+static void	TEST_prog_init ();
+static void	TEST_prog_end ();
+
+
+
+int main (int argc, char *argv [])
+{
+	using namespace std;
+
+	int				ret_val = 0;
+
+	TEST_prog_init ();
+
+	try
+	{
+		if (ret_val == 0)
+		{
+			ret_val = TEST_perform_test_accuracy_all ();
+		}
+
+		if (ret_val == 0)
+		{
+			ret_val = TEST_perform_test_speed_all ();
+		}
+	}
+
+	catch (std::exception &e)
+	{
+		printf ("\n*** main(): Exception (std::exception) : %s\n", e.what ());
+		ret_val = -1;
+	}
+
+	catch (...)
+	{
+		printf ("\n*** main(): Undefined exception\n");
+		ret_val = -1;
+	}
+
+	TEST_prog_end ();
+
+	return (ret_val);
+}
+
+
+
+int	TEST_perform_test_accuracy_all ()
+{
+   int            ret_val = 0;
+
+	TestHelperNormal <float >::perform_test_accuracy (ret_val);
+	TestHelperNormal <double>::perform_test_accuracy (ret_val);
+
+   TestHelperFixLen < 1>::perform_test_accuracy (ret_val);
+   TestHelperFixLen < 2>::perform_test_accuracy (ret_val);
+   TestHelperFixLen < 3>::perform_test_accuracy (ret_val);
+   TestHelperFixLen < 4>::perform_test_accuracy (ret_val);
+   TestHelperFixLen < 7>::perform_test_accuracy (ret_val);
+   TestHelperFixLen < 8>::perform_test_accuracy (ret_val);
+   TestHelperFixLen <10>::perform_test_accuracy (ret_val);
+   TestHelperFixLen <12>::perform_test_accuracy (ret_val);
+   TestHelperFixLen <13>::perform_test_accuracy (ret_val);
+
+	return (ret_val);
+}
+
+
+
+int	TEST_perform_test_speed_all ()
+{
+   int            ret_val = 0;
+
+#if defined (test_settings_SPEED_TEST_ENABLED)
+
+	TestHelperNormal <float >::perform_test_speed (ret_val);
+	TestHelperNormal <double>::perform_test_speed (ret_val);
+
+   TestHelperFixLen < 1>::perform_test_speed (ret_val);
+   TestHelperFixLen < 2>::perform_test_speed (ret_val);
+   TestHelperFixLen < 3>::perform_test_speed (ret_val);
+   TestHelperFixLen < 4>::perform_test_speed (ret_val);
+   TestHelperFixLen < 7>::perform_test_speed (ret_val);
+   TestHelperFixLen < 8>::perform_test_speed (ret_val);
+   TestHelperFixLen <10>::perform_test_speed (ret_val);
+   TestHelperFixLen <12>::perform_test_speed (ret_val);
+   TestHelperFixLen <14>::perform_test_speed (ret_val);
+   TestHelperFixLen <16>::perform_test_speed (ret_val);
+   TestHelperFixLen <20>::perform_test_speed (ret_val);
+
+#endif
+
+   return (ret_val);
+}
+
+
+
+#if defined (_MSC_VER)
+static int __cdecl	TEST_new_handler_cb (size_t dummy)
+{
+	throw std::bad_alloc ();
+	return (0);
+}
+#endif	// _MSC_VER
+
+
+
+#if defined (_MSC_VER) && ! defined (NDEBUG)
+static int	__cdecl	TEST_debug_alloc_hook_cb (int alloc_type, void *user_data_ptr, size_t size, int block_type, long request_nbr, const unsigned char *filename_0, int line_nbr)
+{
+	if (block_type != _CRT_BLOCK)	// Ignore CRT blocks to prevent infinite recursion
+	{
+		switch (alloc_type)
+		{
+		case	_HOOK_ALLOC:
+		case	_HOOK_REALLOC:
+		case	_HOOK_FREE:
+
+			// Put some debug code here
+
+			break;
+
+		default:
+			assert (false);	// Undefined allocation type
+			break;
+		}
+	}
+
+	return (1);
+}
+#endif
+
+
+
+#if defined (_MSC_VER) && ! defined (NDEBUG)
+static int	__cdecl	TEST_debug_report_hook_cb (int report_type, char *user_msg_0, int *ret_val_ptr)
+{
+	*ret_val_ptr = 0;	// 1 to override the CRT default reporting mode
+
+	switch (report_type)
+	{
+	case	_CRT_WARN:
+	case	_CRT_ERROR:
+	case	_CRT_ASSERT:
+
+// Put some debug code here
+
+		break;
+	}
+
+	return (*ret_val_ptr);
+}
+#endif
+
+
+
+static void	TEST_prog_init ()
+{
+#if defined (_MSC_VER)
+	::_set_new_handler (::TEST_new_handler_cb);
+#endif	// _MSC_VER
+
+#if defined (_MSC_VER) && ! defined (NDEBUG)
+	{
+		const int	mode =   (1 * _CRTDBG_MODE_DEBUG)
+						       | (1 * _CRTDBG_MODE_WNDW);
+		::_CrtSetReportMode (_CRT_WARN, mode);
+		::_CrtSetReportMode (_CRT_ERROR, mode);
+		::_CrtSetReportMode (_CRT_ASSERT, mode);
+
+		const int	old_flags = ::_CrtSetDbgFlag (_CRTDBG_REPORT_FLAG);
+		::_CrtSetDbgFlag (  old_flags
+		                  | (1 * _CRTDBG_LEAK_CHECK_DF)
+		                  | (1 * _CRTDBG_CHECK_ALWAYS_DF));
+		::_CrtSetBreakAlloc (-1);	// Specify here a memory bloc number
+		::_CrtSetAllocHook (TEST_debug_alloc_hook_cb);
+		::_CrtSetReportHook (TEST_debug_report_hook_cb);
+
+		// Speed up I/O but breaks C stdio compatibility
+//		std::cout.sync_with_stdio (false);
+//		std::cin.sync_with_stdio (false);
+//		std::cerr.sync_with_stdio (false);
+//		std::clog.sync_with_stdio (false);
+	}
+#endif	// _MSC_VER, NDEBUG
+}
+
+
+
+static void	TEST_prog_end ()
+{
+#if defined (_MSC_VER) && ! defined (NDEBUG)
+	{
+		const int	mode =   (1 * _CRTDBG_MODE_DEBUG)
+						       | (0 * _CRTDBG_MODE_WNDW);
+		::_CrtSetReportMode (_CRT_WARN, mode);
+		::_CrtSetReportMode (_CRT_ERROR, mode);
+		::_CrtSetReportMode (_CRT_ASSERT, mode);
+
+		::_CrtMemState	mem_state;
+		::_CrtMemCheckpoint (&mem_state);
+		::_CrtMemDumpStatistics (&mem_state);
+	}
+#endif	// _MSC_VER, NDEBUG
+}
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/test_fnc.h b/demos/spectrum/fftreal/test_fnc.h
new file mode 100644
index 0000000..2622156
--- /dev/null
+++ b/demos/spectrum/fftreal/test_fnc.h
@@ -0,0 +1,53 @@
+/*****************************************************************************
+
+        test_fnc.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (test_fnc_HEADER_INCLUDED)
+#define	test_fnc_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class T>
+inline T	limit (const T &x, const T &inf, const T &sup);
+
+
+
+#include	"test_fnc.hpp"
+
+
+
+#endif	// test_fnc_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/test_fnc.hpp b/demos/spectrum/fftreal/test_fnc.hpp
new file mode 100644
index 0000000..4b5f9f5
--- /dev/null
+++ b/demos/spectrum/fftreal/test_fnc.hpp
@@ -0,0 +1,56 @@
+/*****************************************************************************
+
+        test_fnc.hpp
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if defined (test_fnc_CURRENT_CODEHEADER)
+	#error Recursive inclusion of test_fnc code header.
+#endif
+#define	test_fnc_CURRENT_CODEHEADER
+
+#if ! defined (test_fnc_CODEHEADER_INCLUDED)
+#define	test_fnc_CODEHEADER_INCLUDED
+
+
+
+/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
+
+
+
+template <class T>
+T	limit (const T &x, const T &inf, const T &sup)
+{
+	assert (! (sup < inf));
+
+	return ((x < inf) ? inf : ((sup < x) ? sup : x));
+}
+
+
+
+#endif	// test_fnc_CODEHEADER_INCLUDED
+
+#undef test_fnc_CURRENT_CODEHEADER
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/test_settings.h b/demos/spectrum/fftreal/test_settings.h
new file mode 100644
index 0000000..b893afc
--- /dev/null
+++ b/demos/spectrum/fftreal/test_settings.h
@@ -0,0 +1,45 @@
+/*****************************************************************************
+
+        test_settings.h
+        Copyright (c) 2005 Laurent de Soras
+
+--- Legal stuff ---
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+*Tab=3***********************************************************************/
+
+
+
+#if ! defined (test_settings_HEADER_INCLUDED)
+#define	test_settings_HEADER_INCLUDED
+
+#if defined (_MSC_VER)
+	#pragma once
+	#pragma warning (4 : 4250) // "Inherits via dominance."
+#endif
+
+
+
+// #undef this label to avoid speed test compilation.
+#define	test_settings_SPEED_TEST_ENABLED
+
+
+
+#endif	// test_settings_HEADER_INCLUDED
+
+
+
+/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/
diff --git a/demos/spectrum/fftreal/testapp.dpr b/demos/spectrum/fftreal/testapp.dpr
new file mode 100644
index 0000000..54f2eb9
--- /dev/null
+++ b/demos/spectrum/fftreal/testapp.dpr
@@ -0,0 +1,150 @@
+program testapp;
+{$APPTYPE CONSOLE}
+uses
+  SysUtils,
+  fftreal in 'fftreal.pas',
+  Math,
+  Windows;
+
+var
+   nbr_points  : longint;
+   x, f        : pflt_array;
+   fft         : TFFTReal;
+   i           : longint;
+   PI          : double;
+   areal, img  : double;
+   f_abs       : double;
+   buffer_size : longint;
+   nbr_tests   : longint;
+   time0, time1, time2 : int64;
+   timereso    : int64;
+   offset      : longint;
+   t0, t1      : double;
+   nbr_s_chn   : longint;
+   tempp1, tempp2 : pflt_array;
+
+begin
+  (*______________________________________________
+   *
+   * Exactness test
+   *______________________________________________
+   *)
+
+  WriteLn('Accuracy test:');
+  WriteLn;
+
+  nbr_points := 16;       // Power of 2
+  GetMem(x, nbr_points * sizeof_flt);
+  GetMem(f, nbr_points * sizeof_flt);
+  fft := TFFTReal.Create(nbr_points);    // FFT object initialized here
+
+  // Test signal
+  PI := ArcTan(1) * 4;
+  for i := 0 to nbr_points-1 do
+  begin
+    x^[i] := -1 + sin (3*2*PI*i/nbr_points)
+                + cos (5*2*PI*i/nbr_points) * 2
+                - sin (7*2*PI*i/nbr_points) * 3
+                + cos (8*2*PI*i/nbr_points) * 5;
+  end;
+
+  // Compute FFT and IFFT
+  fft.do_fft(f, x);
+  fft.do_ifft(f, x);
+  fft.rescale(x);
+
+  // Display the result
+  WriteLn('FFT:');
+  for i := 0 to nbr_points div 2 do
+  begin
+    areal := f^[i];
+    if (i > 0) and (i < nbr_points div 2) then
+      img := f^[i + nbr_points div 2]
+    else
+      img := 0;
+
+    f_abs := Sqrt(areal * areal + img * img);
+    WriteLn(Format('%5d: %12.6f %12.6f (%12.6f)', [i, areal, img, f_abs]));
+  end;
+
+  WriteLn;
+  WriteLn('IFFT:');
+  for i := 0 to nbr_points-1 do
+    WriteLn(Format('%5d: %f', [i, x^[i]]));
+
+  WriteLn;
+
+  FreeMem(x);
+  FreeMem(f);
+  fft.Free;
+
+
+  (*______________________________________________
+   *
+   * Speed test
+   *______________________________________________
+   *)
+
+  WriteLn('Speed test:');
+  WriteLn('Please wait...');
+  WriteLn;
+
+  nbr_points := 1024;	          // Power of 2
+  buffer_size := 256*nbr_points;  // Number of flt_t (float or double)
+  nbr_tests := 10000;
+
+  assert(nbr_points <= buffer_size);
+  GetMem(x, buffer_size * sizeof_flt);
+  GetMem(f, buffer_size * sizeof_flt);
+  fft := TFFTReal.Create(nbr_points);					// FFT object initialized here
+
+  // Test signal: noise
+  for i := 0 to nbr_points-1 do
+    x^[i] := Random($7fff) - ($7fff shr 1);
+
+  // timing
+  QueryPerformanceFrequency(timereso);
+  QueryPerformanceCounter(time0);
+
+  for i := 0 to nbr_tests-1 do
+  begin
+    offset := (i * nbr_points) and (buffer_size - 1);
+    tempp1 := f;
+    inc(tempp1, offset);
+    tempp2 := x;
+    inc(tempp2, offset);
+    fft.do_fft(tempp1, tempp2);
+  end;
+
+  QueryPerformanceCounter(time1);
+
+  for i := 0 to nbr_tests-1 do
+  begin
+    offset := (i * nbr_points) and (buffer_size - 1);
+    tempp1 := f;
+    inc(tempp1, offset);
+    tempp2 := x;
+    inc(tempp2, offset);
+    fft.do_ifft(tempp1, tempp2);
+    fft.rescale(x);
+  end;
+
+  QueryPerformanceCounter(time2);
+
+  t0 := ((time1-time0) / timereso) / nbr_tests;
+  t1 := ((time2-time1) / timereso) / nbr_tests;
+
+  WriteLn(Format('%d-points FFT           : %.0f us.', [nbr_points, t0 * 1000000]));
+  WriteLn(Format('%d-points IFFT + scaling: %.0f us.', [nbr_points, t1 * 1000000]));
+
+  nbr_s_chn := Floor(nbr_points / ((t0 + t1) * 44100 * 2));
+  WriteLn(Format('Peak performance: FFT+IFFT on %d mono channels at 44.1 KHz (with overlapping)', [nbr_s_chn]));
+  WriteLn;
+
+  FreeMem(x);
+  FreeMem(f);
+  fft.Free;
+
+  WriteLn('Press [Return] key to terminate...');
+  ReadLn;
+end.
diff --git a/demos/spectrum/spectrum.pri b/demos/spectrum/spectrum.pri
new file mode 100644
index 0000000..c09aa0d
--- /dev/null
+++ b/demos/spectrum/spectrum.pri
@@ -0,0 +1,37 @@
+# The following macros allow certain features and debugging output
+# to be disabled / enabled at compile time.
+
+# Debug output from spectrum calculation
+DEFINES += LOG_SPECTRUMANALYSER
+
+# Debug output from waveform generation
+#DEFINES += LOG_WAVEFORM
+
+# Debug output from engine
+DEFINES += LOG_ENGINE
+
+# Dump input data to spectrum analyer, plus artefact data files
+#DEFINES += DUMP_SPECTRUMANALYSER
+
+# Dump captured audio data
+#DEFINES += DUMP_CAPTURED_AUDIO
+
+# Disable calculation of level
+#DEFINES += DISABLE_LEVEL
+
+# Disable calculation of frequency spectrum
+# If this macro is defined, the FFTReal DLL will not be built
+#DEFINES += DISABLE_FFT
+
+# Disables rendering of the waveform
+#DEFINES += DISABLE_WAVEFORM
+
+# If defined, superimpose the progress bar on the waveform
+DEFINES += SUPERIMPOSE_PROGRESS_ON_WAVEFORM
+
+# Perform spectrum analysis calculation in a separate thread
+DEFINES += SPECTRUM_ANALYSER_SEPARATE_THREAD
+
+# Suppress warnings about strncpy potentially being unsafe, emitted by MSVC
+win32: DEFINES += _CRT_SECURE_NO_WARNINGS
+
diff --git a/demos/spectrum/spectrum.pro b/demos/spectrum/spectrum.pro
new file mode 100644
index 0000000..823f610
--- /dev/null
+++ b/demos/spectrum/spectrum.pro
@@ -0,0 +1,39 @@
+include(spectrum.pri)
+
+TEMPLATE = subdirs
+
+# Ensure that library is built before application
+CONFIG  += ordered
+
+!contains(DEFINES, DISABLE_FFT) {
+    SUBDIRS += fftreal
+}
+
+SUBDIRS += app
+
+TARGET = spectrum
+
+symbian {
+    # Create a 'make sis' rule which can be run from the top-level
+
+    include($$QT_SOURCE_TREE/demos/symbianpkgrules.pri)
+
+    # UID for the SIS file
+    TARGET.UID3 = 0xA000E3FA
+
+    epoc32_dir = $${EPOCROOT}epoc32
+    release_dir = $${epoc32_dir}/release/$(PLATFORM)/$(TARGET)
+
+    bin.sources     = $${release_dir}/spectrum.exe
+    !contains(DEFINES, DISABLE_FFT) {
+        bin.sources += $${release_dir}/fftreal.dll
+    }
+    bin.path        = !:/sys/bin
+    rsc.sources     = $${epoc32_dir}/data/z/resource/apps/spectrum.rsc
+    rsc.path        = !:/resource/apps
+    mif.sources     = $${epoc32_dir}/data/z/resource/apps/spectrum.mif
+    mif.path        = !:/resource/apps
+    reg_rsc.sources = $${epoc32_dir}/data/z/private/10003a3f/import/apps/spectrum_reg.rsc
+    reg_rsc.path    = !:/private/10003a3f/import/apps
+    DEPLOYMENT += bin rsc mif reg_rsc
+}