QCameraExposureControl Class

The QCameraExposureControl class allows controlling camera exposure parameters. More...

Header: #include <QCameraExposureControl>
qmake: QT += multimedia
Inherits: QMediaControl

Public Types

enum ExposureParameter { ISO, Aperture, ShutterSpeed, ExposureCompensation, ..., ExtendedExposureParameter }

Public Functions

virtual ~QCameraExposureControl()
virtual QVariant actualValue(QCameraExposureControl::ExposureParameter parameter) const = 0
virtual bool isParameterSupported(QCameraExposureControl::ExposureParameter parameter) const = 0
virtual QVariant requestedValue(QCameraExposureControl::ExposureParameter parameter) const = 0
virtual bool setValue(QCameraExposureControl::ExposureParameter parameter, const QVariant &value) = 0
virtual QVariantList supportedParameterRange(QCameraExposureControl::ExposureParameter parameter, bool *continuous) const = 0
  • 31 public functions inherited from QObject

Signals

void actualValueChanged(int parameter)
void parameterRangeChanged(int parameter)
void requestedValueChanged(int parameter)

Static Public Members

const QMetaObject staticMetaObject
  • 9 static public members inherited from QObject

Protected Functions

QCameraExposureControl(QObject *parent = nullptr)
  • 9 protected functions inherited from QObject

Macros

Additional Inherited Members

  • 1 property inherited from QObject
  • 1 public slot inherited from QObject

Detailed Description

The QCameraExposureControl class allows controlling camera exposure parameters.

The QCameraExposure class is the usual method of adjusting exposure related parameters when using camera functionality. This class provides a more complete but less easy to use interface, and also forms the interface to implement when writing a new implementation of QCamera functionality.

You can adjust a number of parameters that will affect images and video taken with the corresponding QCamera object - see the ExposureParameter enumeration.

The interface name of QCameraExposureControl is org.qt-project.qt.cameraexposurecontrol/5.0 as defined in QCameraExposureControl_iid.

See also QCameraExposure and QCamera.

Member Type Documentation

enum QCameraExposureControl::ExposureParameter

ConstantValueDescription
QCameraExposureControl::ISO0Camera ISO sensitivity, specified as integer value.
QCameraExposureControl::Aperture1Lens aperture is specified as an qreal F number. The supported apertures list can change depending on the focal length, in such a case the exposureParameterRangeChanged() signal is emitted.
QCameraExposureControl::ShutterSpeed2Shutter speed in seconds, specified as qreal.
QCameraExposureControl::ExposureCompensation3Exposure compensation, specified as qreal EV value.
QCameraExposureControl::FlashPower4Manual flash power, specified as qreal value. Accepted power range is [0..1.0], with 0 value means no flash and 1.0 corresponds to full flash power.

This value is only used in the manual flash mode.

ConstantValueDescription
QCameraExposureControl::TorchPower6Manual torch power, specified as qreal value. Accepted power range is [0..1.0], with 0 value means no light and 1.0 corresponds to full torch power.

This value is only used in the torch flash mode.

ConstantValueDescription
QCameraExposureControl::FlashCompensation5Flash compensation, specified as qreal EV value.
QCameraExposureControl::SpotMeteringPoint7The relative frame coordinate of the point to use for exposure metering in spot metering mode, specified as a QPointF.
QCameraExposureControl::ExposureMode8Camera exposure mode.
QCameraExposureControl::MeteringMode9Camera metering mode.
QCameraExposureControl::ExtendedExposureParameter1000The base value for platform specific extended parameters. For such parameters the sequential values starting from ExtendedExposureParameter should be used.

Member Function Documentation

[protected] QCameraExposureControl::QCameraExposureControl(QObject *parent = nullptr)

Constructs a camera exposure control object with parent.

[virtual] QCameraExposureControl::~QCameraExposureControl()

Destroys the camera exposure control object.

[pure virtual] QVariant QCameraExposureControl::actualValue(QCameraExposureControl::ExposureParameter parameter) const

[signal] void QCameraExposureControl::actualValueChanged(int parameter)

[pure virtual] bool QCameraExposureControl::isParameterSupported(QCameraExposureControl::ExposureParameter parameter) const

[signal] void QCameraExposureControl::parameterRangeChanged(int parameter)

[pure virtual] QVariant QCameraExposureControl::requestedValue(QCameraExposureControl::ExposureParameter parameter) const

[signal] void QCameraExposureControl::requestedValueChanged(int parameter)

[pure virtual] bool QCameraExposureControl::setValue(QCameraExposureControl::ExposureParameter parameter, const QVariant &value)

[pure virtual] QVariantList QCameraExposureControl::supportedParameterRange(QCameraExposureControl::ExposureParameter parameter, bool *continuous) const

Macro Documentation

QCameraExposureControl_iid

org.qt-project.qt.cameraexposurecontrol/5.0

Defines the interface name of the QCameraExposureControl class.