MediaRecorder QML Type

For encoding and recording media generated in a CaptureSession. More...

Import Statement:	import QtMultimedia
Instantiates:	QMediaRecorder

List of all members, including inherited members

Properties

actualLocation : QUrl
duration : qint64
error : enumeration
errorString : string
isAvailable : bool
mediaFormat : MediaFormat
metaData : mediaMetaData
outputLocation : QUrl
quality : enumeration
recorderState : enumeration

Signals

actualLocationChanged(const QUrl &location)
durationChanged(qint64 duration)
errorOccurred(Error error, const QString &errorString)
metaDataChanged()
recorderStateChanged(RecorderState state)

Methods

pause()
record()
stop()

Detailed Description

The MediaRecorder element can be used within a CaptureSession to record and encode audio and video captured from a microphone and camera

The code below shows a simple capture session containing a MediaRecorder using the default camera and default audio input.

 CaptureSession {
     id: captureSession
     camera: Camera {
         id: camera
     }
     audioInput: AudioInput {}
     recorder: MediaRecorder {
         id: recorder
     }
 }

The code below shows how the recording can be started and stopped.

 CameraButton {
     text: "Record"
     visible: recorder.status !== MediaRecorder.RecordingStatus
     onClicked: recorder.record()
 }

 CameraButton {
     id: stopButton
     text: "Stop"
     visible: recorder.status === MediaRecorder.RecordingStatus
     onClicked: recorder.stop()
 }

See also CaptureSession, Camera, AudioInput, and ImageCapture.

Property Documentation

actualLocation : QUrl

The actual location of the last media content.

The actual location is usually available after recording starts, and reset when new location is set or new recording starts.

duration : qint64

This property holds the recorded media duration in milliseconds.

error : enumeration

This property holds the current media recorder error state.

Constant	Description
`MediaRecorder.NoError`	Not in an error state.
`MediaRecorder.ResourceError`	Not enough system resources
`MediaRecorder.FormatError`	the current format is not supported.
`MediaRecorder.OutOfSpaceError`	No space left on device.
`MediaRecorder.LocationNotWriteable`	The output location is not writable.

errorString : string

This property holds a string describing the current error state.

See also error.

isAvailable : bool

This property holds whether the recorder service is ready to use.

Returns true if media recorder service ready to use.

mediaFormat : MediaFormat

This property holds the current MediaFormat of the recorder.

metaData : mediaMetaData

This property holds meta data associated with the recording.

When a recording is started, any meta-data assigned will be attached to that recording.

Note: Ensure that meta-data is assigned correctly by assigning it before starting the recording.

See also mediaMetaData.

outputLocation : QUrl

The destination location of media content.

Setting the location can fail, for example when the service supports only local file system locations but a network URL was passed. If the operation fails an errorOccured() signal is emitted.

The location can be relative or empty. If empty the recorder uses the system specific place and file naming scheme.

See also errorOccurred().

quality : enumeration

Enumerates quality encoding levels.

Constant	Value
`MediaRecorder.VeryLowQuality`
`MediaRecorder.LowQuality`
`MediaRecorder.NormalQuality`
`MediaRecorder.HighQuality`
`MediaRecorder.VeryHighQuality`

recorderState : enumeration

This property holds the current media recorder state.

The state property represents the user request and is changed synchronously during record(), pause() or stop() calls. RecorderSstate may also change asynchronously when recording fails.

Constant	Description
`MediaRecorder.StoppedState`	The recorder is not active.
`MediaRecorder.RecordingState`	The recording is requested.
`MediaRecorder.PausedState`	The recorder is pause.

Signal Documentation

actualLocationChanged(const QUrl &location)

Signals that the actual location of the recorded media has changed.

This signal is usually emitted when recording starts.

Note: The corresponding handler is onActualLocationChanged.

durationChanged(qint64 duration)

Signals that the duration of the recorded media has changed.

Note: The corresponding handler is onDurationChanged.

errorOccurred(Error error, const QString &errorString)

Signals that an error has occurred.

The errorString contains a description of the error.

Note: The corresponding handler is onErrorOccurred.

metaDataChanged()

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

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

Note: The corresponding handler is onMetaDataChanged.

recorderStateChanged(RecorderState state)

Signals that a media recorder's state has changed.

Note: The corresponding handler is onRecorderStateChanged.

Method Documentation

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.

record()

Starts recording.

While the recorder state is changed immediately to MediaRecorder.RecordingState, recording may start asynchronously.

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

Note: On mobile devices, recording will happen in the orientation the device had when calling record and is locked for the duration of the recording. To avoid artifacts on the user interface, we recommend to keep the user interface locked to the same orientation as long as the recording is ongoing using the contentOrientation property of the Window and unlock it again once the recording is finished.

stop()

Stops recording.

The recorder state is changed to QMediaRecorder.StoppedState.

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