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/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtMultimedia module 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 "qaudiodevicefactory_p.h"
#include <QtMultimedia/qaudioengine.h>
#include <QtMultimedia/qaudiodeviceinfo.h>
QT_BEGIN_NAMESPACE
class QAudioDeviceInfoPrivate : public QSharedData
{
public:
QAudioDeviceInfoPrivate():info(0) {}
QAudioDeviceInfoPrivate(const QString &r, const QByteArray &h, QAudio::Mode m):
realm(r), handle(h), mode(m)
{
info = QAudioDeviceFactory::audioDeviceInfo(realm, handle, mode);
}
QAudioDeviceInfoPrivate(const QAudioDeviceInfoPrivate &other):
QSharedData(other),
realm(other.realm), handle(other.handle), mode(other.mode)
{
info = QAudioDeviceFactory::audioDeviceInfo(realm, handle, mode);
}
QAudioDeviceInfoPrivate& operator=(const QAudioDeviceInfoPrivate &other)
{
delete info;
realm = other.realm;
handle = other.handle;
mode = other.mode;
info = QAudioDeviceFactory::audioDeviceInfo(realm, handle, mode);
return *this;
}
~QAudioDeviceInfoPrivate()
{
delete info;
}
QString realm;
QByteArray handle;
QAudio::Mode mode;
QAbstractAudioDeviceInfo* info;
};
/*!
\class QAudioDeviceInfo
\brief The QAudioDeviceInfo class provides an interface to query audio devices and their functionality.
\inmodule QtMultimedia
\ingroup multimedia
\since 4.6
QAudioDeviceInfo lets you query for audio devices--such as sound
cards and USB headsets--that are currently available on the system.
The audio devices available are dependent on the platform or audio plugins installed.
You can also query each device for the formats it supports. A
format in this context is a set consisting of a specific byte
order, channel, codec, frequency, sample rate, and sample type. A
format is represented by the QAudioFormat class.
The values supported by the the device for each of these
parameters can be fetched with
supportedByteOrders(), supportedChannels(), supportedCodecs(),
supportedFrequencies(), supportedSampleSizes(), and
supportedSampleTypes(). The combinations supported are dependent on the platform,
audio plugins installed and the audio device capabilities. If you need a specific format, you can check if
the device supports it with isFormatSupported(), or fetch a
supported format that is as close as possible to the format with
nearestFormat(). For instance:
\snippet doc/src/snippets/audio/main.cpp 1
\dots 8
\snippet doc/src/snippets/audio/main.cpp 2
A QAudioDeviceInfo is used by Qt to construct
classes that communicate with the device--such as
QAudioInput, and QAudioOutput. The static
functions defaultInputDevice(), defaultOutputDevice(), and
deviceList() let you get a list of all available
devices. Devices are fetch according to the value of mode
this is specified by the QAudio::Mode enum.
The QAudioDeviceInfo returned are only valid for the QAudio::Mode.
For instance:
\code
foreach(const QAudioDeviceInfo &deviceInfo, QAudioDeviceInfo::deviceList(QAudio::AudioOutput))
qDebug() << "Device name: " << deviceInfo.deviceName();
\endcode
In this code sample, we loop through all devices that are able to output
sound, i.e., play an audio stream in a supported format. For each device we
find, we simply print the deviceName().
\sa QAudioOutput, QAudioInput
*/
/*!
Constructs an empty QAudioDeviceInfo object.
*/
QAudioDeviceInfo::QAudioDeviceInfo():
d(new QAudioDeviceInfoPrivate)
{
}
/*!
Constructs a copy of \a other.
*/
QAudioDeviceInfo::QAudioDeviceInfo(const QAudioDeviceInfo& other):
d(other.d)
{
}
/*!
Destroy this audio device info.
*/
QAudioDeviceInfo::~QAudioDeviceInfo()
{
}
/*!
Sets the QAudioDeviceInfo object to be equal to \a other.
*/
QAudioDeviceInfo& QAudioDeviceInfo::operator=(const QAudioDeviceInfo &other)
{
d = other.d;
return *this;
}
/*!
Returns whether this QAudioDeviceInfo object holds a device definition.
*/
bool QAudioDeviceInfo::isNull() const
{
return d->info == 0;
}
/*!
Returns human readable name of audio device.
Device names vary depending on platform/audio plugin being used.
They are a unique string identifiers for the audio device.
eg. default, Intel, U0x46d0x9a4
*/
QString QAudioDeviceInfo::deviceName() const
{
return isNull() ? QString() : d->info->deviceName();
}
/*!
Returns true if \a settings are supported by the audio device of this QAudioDeviceInfo.
*/
bool QAudioDeviceInfo::isFormatSupported(const QAudioFormat &settings) const
{
return isNull() ? false : d->info->isFormatSupported(settings);
}
/*!
Returns QAudioFormat of default settings.
These settings are provided by the platform/audio plugin being used.
They also are dependent on the QAudio::Mode being used.
A typical audio system would provide something like:
\list
\o Input settings: 8000Hz mono 8 bit.
\o Output settings: 44100Hz stereo 16 bit little endian.
\endlist
*/
QAudioFormat QAudioDeviceInfo::preferredFormat() const
{
return isNull() ? QAudioFormat() : d->info->preferredFormat();
}
/*!
Returns closest QAudioFormat to \a settings that system audio supports.
These settings are provided by the platform/audio plugin being used.
They also are dependent on the QAudio::Mode being used.
*/
QAudioFormat QAudioDeviceInfo::nearestFormat(const QAudioFormat &settings) const
{
return isNull() ? QAudioFormat() : d->info->nearestFormat(settings);
}
/*!
Returns a list of supported codecs.
All platform and plugin implementations should provide support for:
"audio/pcm" - Linear PCM
For writing plugins to support additional codecs refer to:
http://www.iana.org/assignments/media-types/audio/
*/
QStringList QAudioDeviceInfo::supportedCodecs() const
{
return isNull() ? QStringList() : d->info->codecList();
}
/*!
Returns a list of supported frequencies.
*/
QList<int> QAudioDeviceInfo::supportedFrequencies() const
{
return isNull() ? QList<int>() : d->info->frequencyList();
}
/*!
Returns a list of supported channels.
*/
QList<int> QAudioDeviceInfo::supportedChannels() const
{
return isNull() ? QList<int>() : d->info->channelsList();
}
/*!
Returns a list of supported sample sizes.
*/
QList<int> QAudioDeviceInfo::supportedSampleSizes() const
{
return isNull() ? QList<int>() : d->info->sampleSizeList();
}
/*!
Returns a list of supported byte orders.
*/
QList<QAudioFormat::Endian> QAudioDeviceInfo::supportedByteOrders() const
{
return isNull() ? QList<QAudioFormat::Endian>() : d->info->byteOrderList();
}
/*!
Returns a list of supported sample types.
*/
QList<QAudioFormat::SampleType> QAudioDeviceInfo::supportedSampleTypes() const
{
return isNull() ? QList<QAudioFormat::SampleType>() : d->info->sampleTypeList();
}
/*!
Returns the name of the default input audio device.
All platform and audio plugin implementations provide a default audio device to use.
*/
QAudioDeviceInfo QAudioDeviceInfo::defaultInputDevice()
{
return QAudioDeviceFactory::defaultInputDevice();
}
/*!
Returns the name of the default output audio device.
All platform and audio plugin implementations provide a default audio device to use.
*/
QAudioDeviceInfo QAudioDeviceInfo::defaultOutputDevice()
{
return QAudioDeviceFactory::defaultOutputDevice();
}
/*!
Returns a list of audio devices that support \a mode.
*/
QList<QAudioDeviceInfo> QAudioDeviceInfo::deviceList(QAudio::Mode mode)
{
return QAudioDeviceFactory::deviceList(mode);
}
/*!
\internal
*/
QAudioDeviceInfo::QAudioDeviceInfo(const QString &realm, const QByteArray &handle, QAudio::Mode mode):
d(new QAudioDeviceInfoPrivate(realm, handle, mode))
{
}
/*!
\internal
*/
QString QAudioDeviceInfo::realm() const
{
return d->realm;
}
/*!
\internal
*/
QByteArray QAudioDeviceInfo::handle() const
{
return d->handle;
}
/*!
\internal
*/
QAudio::Mode QAudioDeviceInfo::mode() const
{
return d->mode;
}
QT_END_NAMESPACE
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