内容

• 公共类型
• 特性
• 公共函数
• 公共槽
• 信号
• 详细描述

QCameraExposure 类

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

头：	#include <QCameraExposure>
qmake:	QT += multimedia
继承：	QObject

• 所有成员列表，包括继承成员

公共类型

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

特性

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

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

• 1 特性继承自 QObject

公共函数

qreal	aperture () const
qreal	exposureCompensation () const
ExposureMode	exposureMode () const
FlashModes	flashMode () const
bool	isAvailable () const
bool	isExposureModeSupported (ExposureMode mode ) const
bool	isFlashModeSupported (FlashModes mode ) const
bool	isFlashReady () const
bool	isMeteringModeSupported (MeteringMode mode ) const
int	isoSensitivity () const
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 = Q_NULLPTR) const
QList<int>	supportedIsoSensitivities (bool * continuous = Q_NULLPTR) const
QList<qreal>	supportedShutterSpeeds (bool * continuous = Q_NULLPTR) const

• 32 公共函数继承自 QObject

公共槽

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

• 1 公共槽继承自 QObject

信号

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

• 2 信号继承自 QObject

额外继承成员

• 11 静态公共成员继承自 QObject
• 9 保护函数继承自 QObject

详细描述

The QCameraExposure class provides interface for exposure related camera settings.

成员类型文档编制

enum QCameraExposure:: ExposureMode

常量	值	描述
QCameraExposure::ExposureAuto	0	自动模式。
QCameraExposure::ExposureManual	1	手动模式。
QCameraExposure::ExposurePortrait	2	肖象曝光模式。
QCameraExposure::ExposureNight	3	夜间模式。
QCameraExposure::ExposureBacklight	4	背光曝光模式。
QCameraExposure::ExposureSpotlight	5	聚光灯曝光模式。
QCameraExposure::ExposureSports	6	亮点曝光模式。
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:: FlashMode
flags QCameraExposure:: FlashModes

常量	值	描述
QCameraExposure::FlashAuto	0x1	自动闪光。
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

常量	值	描述
QCameraExposure::MeteringMatrix	1	Matrix metering mode.
QCameraExposure::MeteringAverage	2	Center weighted average metering mode.
QCameraExposure::MeteringSpot	3	Spot metering mode.

特性文档编制

aperture : const qreal

Lens aperture is specified as an F number, the ratio of the focal length to effective aperture diameter.

访问函数：

qreal

aperture () const

通知程序信号：

void	apertureChanged (qreal value )

另请参阅 supportedApertures (), setAutoAperture (), setManualAperture ()，和 requestedAperture ().

exposureCompensation : qreal

Exposure compensation in EV units.

Exposure compensation property allows to adjust the automatically calculated exposure.

访问函数：

qreal	exposureCompensation () const
void	setExposureCompensation (qreal ev )

通知程序信号：

void	exposureCompensationChanged (qreal value )

exposureMode : QCameraExposure::ExposureMode

This property holds the exposure mode being used.

访问函数：

ExposureMode	exposureMode () const
void	setExposureMode (ExposureMode mode )

另请参阅 QCameraExposure::isExposureModeSupported ().

flashMode : QCameraExposure::FlashModes

This property holds the flash mode being used.

Usually the single QCameraExposure::FlashMode flag is used, but some non conflicting flags combination are also allowed, like QCameraExposure::FlashManual | QCameraExposure::FlashSlowSyncRearCurtain .

访问函数：

FlashModes	flashMode () const
void	setFlashMode (FlashModes mode )

另请参阅 QCameraExposure::isFlashModeSupported () 和 QCameraExposure::isFlashReady ().

flashReady : const bool

Indicates if the flash is charged and ready to use.

访问函数：

bool	isFlashReady () const

通知程序信号：

void	flashReady (bool ready )

isoSensitivity : const int

This property holds the sensor ISO sensitivity.

访问函数：

int	isoSensitivity () const

通知程序信号：

void	isoSensitivityChanged (int value )

另请参阅 supportedIsoSensitivities (), setAutoIsoSensitivity ()，和 setManualIsoSensitivity ().

meteringMode : QCameraExposure::MeteringMode

This property holds the metering mode being used.

访问函数：

MeteringMode	meteringMode () const
void	setMeteringMode (MeteringMode mode )

另请参阅 QCameraExposure::isMeteringModeSupported ().

shutterSpeed : const qreal

Camera's shutter speed in seconds.

访问函数：

qreal

shutterSpeed () const

通知程序信号：

void	shutterSpeedChanged (qreal speed )

另请参阅 supportedShutterSpeeds (), setAutoShutterSpeed ()，和 setManualShutterSpeed ().

成员函数文档编制

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

Signal emitted when aperature changes to value .

注意： 通知程序信号对于特性 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 .

注意： 通知程序信号对于特性 exposureCompensation .

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

Signal the flash ready status has changed.

注意： 通知程序信号对于特性 flashReady .

bool QCameraExposure:: isAvailable () const

Returns true if exposure settings are supported by this camera.

bool QCameraExposure:: isExposureModeSupported ( ExposureMode mode ) const

Returns true if the exposure mode is supported.

bool QCameraExposure:: isFlashModeSupported ( FlashModes mode ) const

Returns true if the flash mode is supported.

bool QCameraExposure:: isFlashReady () const

Returns true if flash is charged.

注意： Getter 函数对于特性 flashReady .

bool QCameraExposure:: isMeteringModeSupported ( MeteringMode mode ) const

Returns true if the metering mode is supported.

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

Signal emitted when sensitivity changes to value .

注意： 通知程序信号对于特性 isoSensitivity .

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.

[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 值。

[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

void QCameraExposure:: setSpotMeteringPoint (const QPointF & point )

Allows setting the spot metering point to point .

另请参阅 spotMeteringPoint ().

qreal QCameraExposure:: shutterSpeed () const

Returns the current shutter speed in seconds.

注意： Getter 函数对于特性 shutterSpeed .

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

Signals that a camera's shutter speed 已改变。

注意： 通知程序信号对于特性 shutterSpeed .

[signal] void QCameraExposure:: shutterSpeedRangeChanged ()

Signal emitted when the shutter speed range has changed.

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.

另请参阅 setSpotMeteringPoint ().

QList < qreal > QCameraExposure:: supportedApertures ( bool * continuous = Q_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 () 信号被发射。

If the camera supports arbitrary aperture values within the supported range, * continuous 被设为 true，否则 * continuous 被设为 false。

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

Returns the list of ISO senitivities camera supports.

If the camera supports arbitrary ISO sensitivities within the supported range, * continuous 被设为 true，否则 * continuous 被设为 false。

QList < qreal > QCameraExposure:: supportedShutterSpeeds ( bool * continuous = Q_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 被设为 true，否则 * continuous 被设为 false。