The QAudioDevice class provides an information about audio devices and their functionality. More...
| Header: | #include <QAudioDevice> |
| CMake: | find_package(Qt6 REQUIRED COMPONENTS Multimedia) target_link_libraries(mytarget PRIVATE Qt6::Multimedia) |
| qmake: | QT += multimedia |
| enum | Mode { Null, Input, Output } |
| QAudioDevice(QAudioDevice &&other) | |
| QAudioDevice(const QAudioDevice &other) | |
| QAudioDevice() | |
| QAudioDevice & | operator=(const QAudioDevice &other) |
| QAudioDevice & | operator=(QAudioDevice &&other) |
| ~QAudioDevice() | |
| QAudioFormat::ChannelConfig | channelConfiguration() const |
| QString | description() const |
| QByteArray | id() const |
| bool | isDefault() const |
| bool | isFormatSupported(const QAudioFormat &settings) const |
| bool | isNull() const |
| int | maximumChannelCount() const |
| int | maximumSampleRate() const |
| int | minimumChannelCount() const |
| int | minimumSampleRate() const |
| QAudioDevice::Mode | mode() const |
| QAudioFormat | preferredFormat() const |
| QList<QAudioFormat::SampleFormat> | supportedSampleFormats() const |
| void | swap(QAudioDevice &other) |
| bool | operator!=(const QAudioDevice &other) const |
| bool | operator==(const QAudioDevice &other) const |
QAudioDevice describes an audio device available in the system, either for input or for playback.
A QAudioDevice is used by Qt to construct classes that communicate with the device -- such as QAudioSource, and QAudioSink. It is also used to determine the input or output device to use in a capture session or during media playback.
You can also query each device for the formats it supports. A format in this context is a set consisting of a channel count, sample rate, and sample type. A format is represented by the QAudioFormat class.
The values supported by the device for each of these parameters can be fetched with minimumChannelCount(), maximumChannelCount(), minimumSampleRate(), maximumSampleRate() and supportedSampleFormats(). The combinations supported are dependent on the audio device capabilities. If you need a specific format, you can check if the device supports it with isFormatSupported(). For instance:
{
sourceFile.setFileName("/tmp/test.raw");
sourceFile.open(QIODevice::ReadOnly);
QAudioFormat format;
// Set up the format, eg.
format.setSampleRate(8000);
format.setChannelCount(1);
format.setSampleFormat(QAudioFormat::UInt8);
QAudioDevice info(QAudioDevice::defaultOutputDevice());
if (!info.isFormatSupported(format)) {
qWarning() << "Raw audio format not supported by backend, cannot play audio.";
return;
}
audio = new QAudioSink(format, this);
connect(audio, SIGNAL(stateChanged(QAudio::State)), this, SLOT(handleStateChanged(QAudio::State)));
audio->start(&sourceFile);
}
The set of available devices can be retrieved from the QMediaDevices class.
For instance:
const auto deviceInfos = QMediaDevices::availableDevices(QAudioDevice::Output); for (const QAudioDevice &deviceInfo : deviceInfos) qDebug() << "Device: " << deviceInfo.description();
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().
See also QAudioSink,QAudioSource,QAudioFormat.
Describes the mode of this device.
| Constant | Value | Description |
|---|---|---|
QAudioDevice::Null |
0 |
A null device. |
QAudioDevice::Input |
1 |
An input device. |
QAudioDevice::Output |
2 |
An output device. |
[read-only] description : const QStringReturns a human readable name of the audio device.
Use this string to present the device to the user.
Access functions:
| QString | description() const |
[read-only] id : const QByteArrayReturns an identifier for the audio device.
Device names vary depending on the platform/audio plugin being used.
They are a unique identifier for the audio device.
Access functions:
| QByteArray | id() const |
[read-only] isDefault : const boolReturns true if this is the default audio device.
Access functions:
| bool | isDefault() const |
[read-only] mode : const ModeReturns whether this device is an input or output device.
Access functions:
| QAudioDevice::Mode | mode() const |
Move constructs from other.
Constructs a copy of other.
Constructs a null QAudioDevice object.
Sets the QAudioDevice object to be equal to other.
Moves other into this QAudioDevice object.
Destroy this audio device info.
Returns the channel configuration of the device.
Returns true if the supplied settings are supported by the audio device described by this QAudioDevice.
Returns whether this QAudioDevice object holds a valid device definition.
Returns the maximum number of supported channel counts.
This is typically 1 for mono sound, or 2 for stereo sound.
Returns the maximum supported sample rate (in Hertz).
Returns the minimum number of supported channel counts.
This is typically 1 for mono sound, or 2 for stereo sound.
Returns the minimum supported sample rate (in Hertz).
Returns the default audio format settings for this device.
These settings are provided by the platform/audio plugin being used.
They are also dependent on the QAudio::Mode being used.
A typical audio system would provide something like:
Returns a list of supported sample types.
Swaps the audio device with the other.
Returns true if this QAudioDevice class represents a different audio device than other
Returns true if this QAudioDevice class represents the same audio device as other.
