QCameraExposure Class

The QCameraExposure class provides interface for exposure related camera settings. More...

Header:	#include <QCameraExposure>
qmake:	QT += multimedia
Inherits:	QObject

• List of all members, including inherited members

Public Types

enum	ExposureMode { ExposureAuto, ExposureManual, ExposurePortrait, ExposureNight, ExposureBacklight, …, ExposureModeVendor }
enum	FlashMode { FlashAuto, FlashOff, FlashOn, FlashRedEyeReduction, FlashFill, …, FlashManual }
flags	FlashModes
enum	MeteringMode { MeteringMatrix, MeteringAverage, MeteringSpot }

Properties

aperture : const qreal exposureCompensation : qreal exposureMode : QCameraExposure::ExposureMode flashMode : QCameraExposure::FlashModes

flashReady : const bool isoSensitivity : const int meteringMode : QCameraExposure::MeteringMode shutterSpeed : const qreal

Public Functions

qreal	aperture() const
qreal	exposureCompensation() const
QCameraExposure::ExposureMode	exposureMode() const
QCameraExposure::FlashModes	flashMode() const
bool	isAvailable() const
bool	isExposureModeSupported(QCameraExposure::ExposureMode mode) const
bool	isFlashModeSupported(QCameraExposure::FlashModes mode) const
bool	isFlashReady() const
bool	isMeteringModeSupported(QCameraExposure::MeteringMode mode) const
int	isoSensitivity() const
QCameraExposure::MeteringMode	meteringMode() const
qreal	requestedAperture() const
int	requestedIsoSensitivity() const
qreal	requestedShutterSpeed() const
void	setSpotMeteringPoint(const QPointF &point)
qreal	shutterSpeed() const
QPointF	spotMeteringPoint() const
QList<qreal>	supportedApertures(bool *continuous = nullptr) const
QList<int>	supportedIsoSensitivities(bool *continuous = nullptr) const
QList<qreal>	supportedShutterSpeeds(bool *continuous = nullptr) const

Public Slots

void	setAutoAperture()
void	setAutoIsoSensitivity()
void	setAutoShutterSpeed()
void	setExposureCompensation(qreal ev)
void	setExposureMode(QCameraExposure::ExposureMode mode)
void	setFlashMode(QCameraExposure::FlashModes mode)
void	setManualAperture(qreal aperture)
void	setManualIsoSensitivity(int iso)
void	setManualShutterSpeed(qreal seconds)
void	setMeteringMode(QCameraExposure::MeteringMode mode)

Signals

void	apertureChanged(qreal value)
void	apertureRangeChanged()
void	exposureCompensationChanged(qreal value)
void	flashReady(bool ready)
void	isoSensitivityChanged(int value)
void	shutterSpeedChanged(qreal speed)
void	shutterSpeedRangeChanged()

Protected Functions

virtual

~QCameraExposure()

Detailed Description

Member Type Documentation

enum QCameraExposure::ExposureMode

Constant	Value	Description
QCameraExposure::ExposureAuto	0	Automatic mode.
QCameraExposure::ExposureManual	1	Manual mode.
QCameraExposure::ExposurePortrait	2	Portrait exposure mode.
QCameraExposure::ExposureNight	3	Night mode.
QCameraExposure::ExposureBacklight	4	Backlight exposure mode.
QCameraExposure::ExposureSpotlight	5	Spotlight exposure mode.
QCameraExposure::ExposureSports	6	Spots exposure mode.
QCameraExposure::ExposureSnow	7	Snow exposure mode.
QCameraExposure::ExposureBeach	8	Beach exposure mode.
QCameraExposure::ExposureLargeAperture	9	Use larger aperture with small depth of field.
QCameraExposure::ExposureSmallAperture	10	Use smaller aperture.
QCameraExposure::ExposureAction	11	Action mode. Since 5.5
QCameraExposure::ExposureLandscape	12	Landscape mode. Since 5.5
QCameraExposure::ExposureNightPortrait	13	Night portrait mode. Since 5.5
QCameraExposure::ExposureTheatre	14	Theatre mode. Since 5.5
QCameraExposure::ExposureSunset	15	Sunset mode. Since 5.5
QCameraExposure::ExposureSteadyPhoto	16	Steady photo mode. Since 5.5
QCameraExposure::ExposureFireworks	17	Fireworks mode. Since 5.5
QCameraExposure::ExposureParty	18	Party mode. Since 5.5
QCameraExposure::ExposureCandlelight	19	Candlelight mode. Since 5.5
QCameraExposure::ExposureBarcode	20	Barcode mode. Since 5.5
QCameraExposure::ExposureModeVendor	1000	The base value for device specific exposure modes.

enum QCameraExposure::FlashModeflags QCameraExposure::FlashModes

Constant	Value	Description
QCameraExposure::FlashAuto	0x1	Automatic flash.
QCameraExposure::FlashOff	0x2	Flash is Off.
QCameraExposure::FlashOn	0x4	Flash is On.
QCameraExposure::FlashRedEyeReduction	0x8	Red eye reduction flash.
QCameraExposure::FlashFill	0x10	Use flash to fillin shadows.
QCameraExposure::FlashTorch	0x20	Constant light source. If supported, torch can be enabled without loading the camera.
QCameraExposure::FlashVideoLight	0x40	Constant light source, useful for video capture. The light is turned on only while camera is active.
QCameraExposure::FlashSlowSyncFrontCurtain	0x80	Use the flash in conjunction with a slow shutter speed. This mode allows better exposure of distant objects and/or motion blur effect.
QCameraExposure::FlashSlowSyncRearCurtain	0x100	The similar mode to FlashSlowSyncFrontCurtain but flash is fired at the end of exposure.
QCameraExposure::FlashManual	0x200	Flash power is manualy set.

The FlashModes type is a typedef for QFlags<FlashMode>. It stores an OR combination of FlashMode values.

enum QCameraExposure::MeteringMode

Constant	Value	Description
QCameraExposure::MeteringMatrix	1	Matrix metering mode.
QCameraExposure::MeteringAverage	2	Center weighted average metering mode.
QCameraExposure::MeteringSpot	3	Spot metering mode.

Member Function Documentation

[signal] void QCameraExposure::apertureChanged(qreal value)

Signal emitted when aperature changes to value.

Note: Notifier signal for property aperture.

[signal] void QCameraExposure::apertureRangeChanged()

Signal emitted when aperature range has changed.

[signal] void QCameraExposure::exposureCompensationChanged(qreal value)

Signal emitted when the exposure compensation changes to value.

Note: Notifier signal for property exposureCompensation.

[signal] void QCameraExposure::flashReady(bool ready)

Signal the flash ready status has changed.

Note: Notifier signal for property flashReady.

[signal] void QCameraExposure::isoSensitivityChanged(int value)

Signal emitted when sensitivity changes to value.

Note: Notifier signal for property isoSensitivity.

[slot] void QCameraExposure::setAutoAperture()

Turn on auto aperture

[slot] void QCameraExposure::setAutoIsoSensitivity()

Turn on auto sensitivity

[slot] void QCameraExposure::setAutoShutterSpeed()

Turn on auto shutter speed

[slot] void QCameraExposure::setManualAperture(qreal aperture)

Sets the manual camera aperture value.

[slot] void QCameraExposure::setManualIsoSensitivity(int iso)

Sets the manual sensitivity to iso

[slot] void QCameraExposure::setManualShutterSpeed(qreal seconds)

Set the manual shutter speed to seconds

[signal] void QCameraExposure::shutterSpeedChanged(qreal speed)

Signals that a camera's shutter speed has changed.

Note: Notifier signal for property shutterSpeed.

[signal] void QCameraExposure::shutterSpeedRangeChanged()

Signal emitted when the shutter speed range has changed.

[virtual protected] QCameraExposure::~QCameraExposure()

Destroys the camera exposure object.

bool QCameraExposure::isAvailable() const

Returns true if exposure settings are supported by this camera.

bool QCameraExposure::isExposureModeSupported(QCameraExposure::ExposureMode mode) const

Returns true if the exposure mode is supported.

bool QCameraExposure::isFlashModeSupported(QCameraExposure::FlashModes mode) const

Returns true if the flash mode is supported.

bool QCameraExposure::isFlashReady() const

Returns true if flash is charged.

Note: Getter function for property flashReady.

bool QCameraExposure::isMeteringModeSupported(QCameraExposure::MeteringMode mode) const

Returns true if the metering mode is supported.

qreal QCameraExposure::requestedAperture() const

Returns the requested manual aperture or -1.0 if automatic aperture is turned on.

int QCameraExposure::requestedIsoSensitivity() const

Returns the requested ISO sensitivity or -1 if automatic ISO is turned on.

qreal QCameraExposure::requestedShutterSpeed() const

Returns the requested manual shutter speed in seconds or -1.0 if automatic shutter speed is turned on.

void QCameraExposure::setSpotMeteringPoint(const QPointF &point)

Allows setting the spot metering point to point.

See also spotMeteringPoint().

qreal QCameraExposure::shutterSpeed() const

Returns the current shutter speed in seconds.

Note: Getter function for property shutterSpeed.

QPointF QCameraExposure::spotMeteringPoint() const

When supported, the spot metering point is the (normalized) position of the point of the image where exposure metering will be performed. This is typically used to indicate an "interesting" area of the image that should be exposed properly.

The coordinates are relative frame coordinates: QPointF(0,0) points to the left top frame point, QPointF(0.5,0.5) points to the frame center, which is typically the default spot metering point.

The spot metering point is only used with spot metering mode.

See also setSpotMeteringPoint().

QList<qreal> QCameraExposure::supportedApertures(bool *continuous = nullptr) const

Returns the list of aperture values camera supports. The apertures list can change depending on the focal length, in such a case the apertureRangeChanged() signal is emitted.

If the camera supports arbitrary aperture values within the supported range, *continuous is set to true, otherwise *continuous is set to false.

QList<int> QCameraExposure::supportedIsoSensitivities(bool *continuous = nullptr) const

Returns the list of ISO senitivities camera supports.

If the camera supports arbitrary ISO sensitivities within the supported range, *continuous is set to true, otherwise *continuous is set to false.

QList<qreal> QCameraExposure::supportedShutterSpeeds(bool *continuous = nullptr) const

Returns the list of shutter speed values in seconds camera supports.

If the camera supports arbitrary shutter speed values within the supported range, *continuous is set to true, otherwise *continuous is set to false.