1 files changed, 138 insertions, 0 deletions
diff --git a/demos/spectrum/app/utils.cpp b/demos/spectrum/app/utils.cpp
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+/****************************************************************************
+**
+** 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;
+}