QMediaRecorder Class

QMediaCaptureSession session;
QAudioInput audioInput;
session.setAudioInput(&input);
QMediaRecorder recorder;
session.setRecorder(&recorder);
recorder.setQuality(QMediaRecorder::HighQuality);
recorder.setOutputLocation(QUrl::fromLocalFile("test.mp3"));
recorder.record();

Member Function Documentation

QMediaRecorder::QMediaRecorder(QObject *parent = nullptr)

Constructs a media recorder. The media recorder is a child of parent.

[virtual noexcept] QMediaRecorder::~QMediaRecorder()

Destroys a media recorder object.

[signal] void QMediaRecorder::actualLocationChanged(const QUrl &location)

Signals that the actual location of the recorded media has changed. This signal is usually emitted when recording starts.

void QMediaRecorder::addMetaData(const QMediaMetaData &metaData)

Adds metaData to the recorded media.

int QMediaRecorder::audioBitRate() const

Returns the bit rate of the compressed audio stream in bits per second.

See also setAudioBitRate().

[signal] void QMediaRecorder::audioBitRateChanged()

Signals when the recording audio bit rate changes.

int QMediaRecorder::audioChannelCount() const

Returns the number of audio channels.

See also setAudioChannelCount().

[signal] void QMediaRecorder::audioChannelCountChanged()

Signals when the recording audio channel count changes.

int QMediaRecorder::audioSampleRate() const

Returns the audio sample rate in Hz.

See also setAudioSampleRate().

[signal] void QMediaRecorder::audioSampleRateChanged()

Signals when the recording audio sample rate changes.

QMediaCaptureSession *QMediaRecorder::captureSession() const

Returns the media capture session.

[signal] void QMediaRecorder::durationChanged(qint64 duration)

Signals that the duration of the recorded media has changed.

[signal] void QMediaRecorder::encoderSettingsChanged()

Signals when the encoder settings change.

QMediaRecorder::EncodingMode QMediaRecorder::encodingMode() const

Returns the encoding mode.

See also setEncodingMode() and EncodingMode.

[signal] void QMediaRecorder::encodingModeChanged()

Signals when the encoding mode changes.

[signal] void QMediaRecorder::errorOccurred(QMediaRecorder::Error error, const QString &errorString)

Signals that an error has occurred, with errorString containing a description of the error.

bool QMediaRecorder::isAvailable() const

Returns true if media recorder service ready to use.

[signal] void QMediaRecorder::metaDataChanged()

Signals that a media object's meta-data has changed.

If multiple meta-data elements are changed metaDataChanged() is emitted once.

QIODevice *QMediaRecorder::outputDevice() const

Returns the output IO device for media content.

See also setOutputDevice().

[slot] void QMediaRecorder::pause()

Pauses recording.

The recorder state is changed to QMediaRecorder::PausedState.

Depending on the platform, pausing recording may be not supported. In this case the recorder state is unchanged.

[signal] void QMediaRecorder::qualityChanged()

Signals when the recording quality changes.

[slot] void QMediaRecorder::record()

Starts recording.

While the recorder state is changed immediately to c{QMediaRecorder::RecordingState}, recording may start asynchronously.

If recording fails error() signal is emitted with recorder state being reset back to QMediaRecorder::StoppedState.

This method updates actualLocation according to its generation rules.

QMediaRecorder::RecorderState QMediaRecorder::recorderState() const

Returns the current media recorder state.

See also QMediaRecorder::RecorderState.

[signal] void QMediaRecorder::recorderStateChanged(QMediaRecorder::RecorderState state)

Signals that a media recorder's state has changed.

void QMediaRecorder::setAudioBitRate(int bitRate)

Sets the audio bitRate in bits per second.

See also audioBitRate().

void QMediaRecorder::setAudioChannelCount(int channels)

Sets the number of audio channels.

A value of -1 indicates the recorder should make an optimal choice based on what is available from the audio source and the limitations of the codec.

See also audioChannelCount().

void QMediaRecorder::setAudioSampleRate(int sampleRate)

Sets the audio sampleRate in Hz.

A value of -1 indicates the recorder should make an optimal choice based on what is available from the audio source, and the limitations of the codec.

See also audioSampleRate().

void QMediaRecorder::setEncodingMode(QMediaRecorder::EncodingMode mode)

Sets the encoding mode setting.

If ConstantQualityEncoding is set, the quality encoding parameter is used and bit rates are ignored, otherwise the bitrates are used.

See also encodingMode() and EncodingMode.

void QMediaRecorder::setMetaData(const QMediaMetaData &metaData)

Sets the meta data to metaData.

See also metaData().

void QMediaRecorder::setOutputDevice(QIODevice *device)

Set the output IO device for media content.

The device must have been opened in the WriteOnly or ReadWrite modes before the recording starts.

The media recorder doesn't take ownership of the specified device. If the recording has been started, the device must be kept alive and open until the signal recorderStateChanged(StoppedState) is emitted.

This method resets actualLocation immediately unless the specified device is null.

If a writable output device is assigned to the recorder, outputLocation is ignored, and actualLocation is not generated when recording starts. This behavior may change in the future, so we recommend setting only one output, either outputLocation or outputDevice.

QMediaRecorder::setOutputDevice is only supported with the FFmpeg backend.

See also outputDevice() and outputLocation.

void QMediaRecorder::setVideoBitRate(int bitRate)

Sets the video bitRate in bits per second.

See also videoBitRate().

void QMediaRecorder::setVideoFrameRate(qreal frameRate)

Sets the video frameRate.

A value of 0 indicates the recorder should make an optimal choice based on what is available from the video source and the limitations of the codec.

See also videoFrameRate().

void QMediaRecorder::setVideoResolution(const QSize &size)

Sets the resolution of the encoded video to size.

Pass an empty QSize to make the recorder choose an optimal resolution based on what is available from the video source and the limitations of the codec.

See also videoResolution().

void QMediaRecorder::setVideoResolution(int width, int height)

Sets the width and height of the resolution of the encoded video.

This is an overloaded function.

[slot] void QMediaRecorder::stop()

The recorder will stop the recording. Processing pending video and audio data might however still take some time. The recording is finished, once the state of the media recorder changes to QMediaRecorder::StoppedState.

int QMediaRecorder::videoBitRate() const

Returns the bit rate of the compressed video stream in bits per second.

See also setVideoBitRate().

[signal] void QMediaRecorder::videoBitRateChanged()

Signals when the recording video bit rate changes.

qreal QMediaRecorder::videoFrameRate() const

Returns the video frame rate.

See also setVideoFrameRate().

[signal] void QMediaRecorder::videoFrameRateChanged()

Signals when the recording video frame rate changes.

QSize QMediaRecorder::videoResolution() const

Returns the resolution of the encoded video.

See also setVideoResolution().

[signal] void QMediaRecorder::videoResolutionChanged()

Signals when the video recording resolution changes.