QCameraImageCapture Class▲
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Header: QCameraImageCapture
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qmake: QT += multimedia
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Inherits: QObject and QMediaBindableInterface
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Group: QCameraImageCapture is part of multimedia, multimedia_camera
Detailed Description▲
The QCameraImageCapture class is a high level images recording class. It's not intended to be used alone but for accessing the media recording functions of other media objects, like QCamera.
camera = new QCamera;
viewfinder = new QCameraViewfinder();
viewfinder->show();
camera->setViewfinder(viewfinder);
imageCapture = new QCameraImageCapture(camera);
camera->setCaptureMode(QCamera::CaptureStillImage);
camera->start();
//on half pressed shutter button
camera->searchAndLock();
//on shutter button pressed
imageCapture->capture();
//on shutter button released
camera->unlock();See Also▲
See also QCamera
Member Type Documentation▲
enum QCameraImageCapture::CaptureDestination▲
flags QCameraImageCapture::CaptureDestinations
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Constant |
Value |
Description |
|---|---|---|
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QCameraImageCapture::CaptureToFile |
0x01 |
Capture the image to a file. |
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QCameraImageCapture::CaptureToBuffer |
0x02 |
Capture the image to a buffer for further processing. |
The CaptureDestinations type is a typedef for QFlags<CaptureDestination>. It stores an OR combination of CaptureDestination values.
enum QCameraImageCapture::DriveMode▲
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Constant |
Value |
Description |
|---|---|---|
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QCameraImageCapture::SingleImageCapture |
0 |
Drive mode is capturing a single picture. |
enum QCameraImageCapture::Error▲
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Constant |
Value |
Description |
|---|---|---|
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QCameraImageCapture::NoError |
0 |
No Errors. |
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QCameraImageCapture::NotReadyError |
1 |
The service is not ready for capture yet. |
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QCameraImageCapture::ResourceError |
2 |
Device is not ready or not available. |
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QCameraImageCapture::OutOfSpaceError |
3 |
No space left on device. |
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QCameraImageCapture::NotSupportedFeatureError |
4 |
Device does not support stillimages capture. |
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QCameraImageCapture::FormatError |
5 |
Current format is not supported. |
Property Documentation▲
[read-only] readyForCapture : const bool▲
This property holds whether the service is ready to capture a an image immediately.
Calling capture() while readyForCapture is false is not permitted and results in an error.
Access functions:
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bool isReadyForCapture() const
Notifier signal:
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void readyForCaptureChanged(bool ready)
Member Function Documentation▲
[explicit] QCameraImageCapture::QCameraImageCapture(QMediaObject *mediaObject, QObject *parent = nullptr)▲
Constructs a media recorder which records the media produced by mediaObject.
The parent is passed to QMediaObject.
[virtual] QCameraImageCapture::~QCameraImageCapture()▲
Destroys images capture object.
QMultimedia::AvailabilityStatus QCameraImageCapture::availability() const▲
Returns the availability of this functionality.
QVideoFrame::PixelFormat QCameraImageCapture::bufferFormat() const▲
Returns the buffer image capture format being used.
See Also▲
See also supportedBufferFormats(), setBufferFormat()
void QCameraImageCapture::bufferFormatChanged(QVideoFrame::PixelFormat format)▲
Signal emitted when the buffer format for the buffer image capture has changed.
void QCameraImageCapture::cancelCapture()▲
Cancel incomplete capture requests. Already captured and queused for proicessing images may be discarded.
int QCameraImageCapture::capture(const QString &file = QString())▲
Capture the image and save it to file. This operation is asynchronous in majority of cases, followed by signals QCameraImageCapture::imageExposed(), QCameraImageCapture::imageCaptured(), QCameraImageCapture::imageSaved() or QCameraImageCapture::error().
If an empty file is passed, the camera backend choses the default location and naming scheme for photos on the system, if only file name without full path is specified, the image will be saved to the default directory, with a full path reported with imageCaptured() and imageSaved() signals.
QCamera saves all the capture parameters like exposure settings or image processing parameters, so changes to camera parameters after capture() is called do not affect previous capture requests.
QCameraImageCapture::capture returns the capture Id parameter, used with imageExposed(), imageCaptured() and imageSaved() signals.
See Also▲
See also isReadyForCapture()
QCameraImageCapture::CaptureDestinations QCameraImageCapture::captureDestination() const▲
Returns the image capture destination being used.
See Also▲
See also isCaptureDestinationSupported(), setCaptureDestination()
void QCameraImageCapture::captureDestinationChanged(QCameraImageCapture::CaptureDestinations destination)▲
Signal emitted when the capture destination has changed.
QImageEncoderSettings QCameraImageCapture::encodingSettings() const▲
QCameraImageCapture::Error QCameraImageCapture::error() const▲
void QCameraImageCapture::error(int id, QCameraImageCapture::Error error, const QString &errorString)▲
Signals that the capture request id has failed with an error and errorString description.
QString QCameraImageCapture::errorString() const▲
void QCameraImageCapture::imageAvailable(int id, const QVideoFrame &frame)▲
Signal emitted when the frame with request id is available.
void QCameraImageCapture::imageCaptured(int id, const QImage &preview)▲
Signal emitted when the frame with request id was captured, but not processed and saved yet. Frame preview can be displayed to user.
QString QCameraImageCapture::imageCodecDescription(const QString &codec) const▲
Returns a description of an image codec.
void QCameraImageCapture::imageExposed(int id)▲
Signal emitted when the frame with request id was exposed.
void QCameraImageCapture::imageMetadataAvailable(int id, const QString &key, const QVariant &value)▲
Signals that a metadata for an image with request id is available. Also includes the key and value of the metadata.
This signal is emitted between imageExposed and imageSaved signals.
void QCameraImageCapture::imageSaved(int id, const QString &fileName)▲
Signal emitted when the frame with request id was saved to fileName.
bool QCameraImageCapture::isAvailable() const▲
Returns true if the images capture service ready to use.
bool QCameraImageCapture::isCaptureDestinationSupported(QCameraImageCapture::CaptureDestinations destination) const▲
Returns true if the image capture destination is supported; otherwise returns false.
See Also▲
See also captureDestination(), setCaptureDestination()
[override virtual] QMediaObject *QCameraImageCapture::mediaObject() const▲
void QCameraImageCapture::readyForCaptureChanged(bool ready)▲
Signals that a camera's ready for capture state has changed.
Notifier signal for property readyForCapture.
void QCameraImageCapture::setBufferFormat(const QVideoFrame::PixelFormat format)▲
Sets the buffer image capture format to be used.
See Also▲
See also bufferFormat(), supportedBufferFormats(), captureDestination()
void QCameraImageCapture::setCaptureDestination(QCameraImageCapture::CaptureDestinations destination)▲
Sets the capture destination to be used.
See Also▲
See also isCaptureDestinationSupported(), captureDestination()
void QCameraImageCapture::setEncodingSettings(const QImageEncoderSettings &settings)▲
Sets the image encoding settings.
If some parameters are not specified, or null settings are passed, the encoder choose the default encoding parameters.
See Also▲
See also encodingSettings()
[override virtual protected] bool QCameraImageCapture::setMediaObject(QMediaObject *mediaObject)▲
Reimplements: QMediaBindableInterface::setMediaObject(QMediaObject *object).
See Also▲
See also mediaObject()
QList<QVideoFrame::PixelFormat> QCameraImageCapture::supportedBufferFormats() const▲
Returns the list of supported buffer image capture formats.
See Also▲
See also bufferFormat(), setBufferFormat()
QStringList QCameraImageCapture::supportedImageCodecs() const▲
Returns a list of supported image codecs.
QList<QSize> QCameraImageCapture::supportedResolutions(const QImageEncoderSettings &settings = QImageEncoderSettings(), bool *continuous = nullptr) const▲
Returns a list of resolutions images can be encoded at.
If non null image settings parameter is passed, the returned list is reduced to resolution supported with partial settings like image codec or quality applied.
If the encoder supports arbitrary resolutions within the supported range, *continuous is set to true, otherwise *continuous is set to false.
See Also▲
See also QImageEncoderSettings::resolution()