QCamera 類

QCamera 類提供係統攝像頭設備的接口。更多...

頭：	`#include <QCamera>`
CMake:	`find_package(Qt6 REQUIRED COMPONENTS Multimedia)` `target_link_libraries(mytarget PRIVATE Qt6::Multimedia)`
qmake:	`QT += multimedia`
在 QML：	Camera
繼承：	QObject

所有成員列錶，包括繼承成員

公共類型

enum	Error { NoError, CameraError }
enum	ExposureMode { ExposureAuto, ExposureManual, ExposurePortrait, ExposureNight, ExposureSports, …, ExposureBarcode }
枚舉類	Feature { ColorTemperature, ExposureCompensation, IsoSensitivity, ManualExposureTime, CustomFocusPoint, FocusDistance }
flags	Features
enum	FlashMode { FlashOff, FlashOn, FlashAuto }
enum	FocusMode { FocusModeAuto, FocusModeAutoNear, FocusModeAutoFar, FocusModeHyperfocal, FocusModeInfinity, FocusModeManual }
enum	TorchMode { TorchOff, TorchOn, TorchAuto }
enum	WhiteBalanceMode { WhiteBalanceAuto, WhiteBalanceManual, WhiteBalanceSunlight, WhiteBalanceCloudy, WhiteBalanceShade, …, WhiteBalanceSunset }

特性

active : bool
cameraDevice : QCameraDevice
cameraFormat : QCameraFormat
colorTemperature : int
customFocusPoint : QPointF
error : const Error
errorString : const QString
exposureCompensation : float
exposureMode : QCamera::ExposureMode
exposureTime : const float
flashMode : QCamera::FlashMode
flashReady : const bool

focusDistance : float
focusMode : FocusMode
focusPoint : const QPointF
isoSensitivity : const int
manualExposureTime : float
manualIsoSensitivity : int
maximumZoomFactor : const float
minimumZoomFactor : const float
supportedFeatures : const Features
torchMode : QCamera::TorchMode
whiteBalanceMode : WhiteBalanceMode
zoomFactor : float

公共函數

	QCamera (QObject * parent = nullptr)
	QCamera (QCameraDevice::Position position , QObject * parent = nullptr)
	QCamera (const QCameraDevice & cameraDevice , QObject * parent = nullptr)
virtual	~QCamera () override
QCameraDevice	cameraDevice () const
QCameraFormat	cameraFormat () const
QMediaCaptureSession *	captureSession () const
int	colorTemperature () const
QPointF	customFocusPoint () const
QCamera::Error	error () const
QString	errorString () const
float	exposureCompensation () const
QCamera::ExposureMode	exposureMode () const
float	exposureTime () const
QCamera::FlashMode	flashMode () const
float	focusDistance () const
QCamera::FocusMode	focusMode () const
QPointF	focusPoint () const
bool	isActive () const
bool	isAvailable () const
bool	isExposureModeSupported (QCamera::ExposureMode mode ) const
bool	isFlashModeSupported (QCamera::FlashMode mode ) const
bool	isFlashReady () const
bool	isFocusModeSupported (QCamera::FocusMode mode ) const
bool	isTorchModeSupported (QCamera::TorchMode mode ) const
bool	isWhiteBalanceModeSupported (QCamera::WhiteBalanceMode mode ) const
int	isoSensitivity () const
float	manualExposureTime () const
int	manualIsoSensitivity () const
float	maximumExposureTime () const
int	maximumIsoSensitivity () const
float	maximumZoomFactor () const
float	minimumExposureTime () const
int	minimumIsoSensitivity () const
float	minimumZoomFactor () const
void	setCameraDevice (const QCameraDevice & cameraDevice )
void	setCameraFormat (const QCameraFormat & format )
void	setCustomFocusPoint (const QPointF & point )
void	setFocusDistance (float d )
void	setFocusMode (QCamera::FocusMode mode )
void	setZoomFactor (float factor )
QCamera::Features	supportedFeatures () const
QCamera::TorchMode	torchMode () const
QCamera::WhiteBalanceMode	whiteBalanceMode () const
float	zoomFactor () const

公共槽

void	setActive (bool active )
void	setAutoExposureTime ()
void	setAutoIsoSensitivity ()
void	setColorTemperature (int colorTemperature )
void	setExposureCompensation (float ev )
void	setExposureMode (QCamera::ExposureMode mode )
void	setFlashMode (QCamera::FlashMode mode )
void	setManualExposureTime (float seconds )
void	setManualIsoSensitivity (int iso )
void	setTorchMode (QCamera::TorchMode mode )
void	setWhiteBalanceMode (QCamera::WhiteBalanceMode mode )
void	start ()
void	stop ()
void	zoomTo (float factor , float rate )

信號

void	activeChanged (bool)
void	cameraDeviceChanged ()
void	cameraFormatChanged ()
void	colorTemperatureChanged () const
void	customFocusPointChanged ()
void	errorChanged ()
void	errorOccurred (QCamera::Error error , const QString & errorString )
void	exposureCompensationChanged (float value )
void	exposureModeChanged ()
void	exposureTimeChanged (float speed )
void	flashModeChanged ()
void	flashReady (bool ready )
void	focusDistanceChanged (float)
void	focusModeChanged ()
void	focusPointChanged ()
void	isoSensitivityChanged (int value )
void	manualExposureTimeChanged (float speed )
void	manualIsoSensitivityChanged (int)
void	maximumZoomFactorChanged (float)
void	minimumZoomFactorChanged (float)
void	supportedFeaturesChanged ()
void	torchModeChanged ()
void	whiteBalanceModeChanged () const
void	zoomFactorChanged (float)

詳細描述

QCamera 可以用於 QMediaCaptureSession 為視頻錄製和圖像獲取。

可以使用 QCameraDevice 列錶可用攝像頭並選取要使用的攝像頭。

const QList<QCameraDevice> cameras = QMediaDevices::videoInputs();
for (const QCameraDevice &cameraDevice : cameras) {
    if (cameraDevice.description() == "mycamera")
        camera = new QCamera(cameraDevice);
}

On hardware that supports it, QCamera lets you adjust the focus and zoom. The minimumZoomFactor and maximumZoomFactor properties provide the range of supported zoom factors. The zoomFactor property allows changing the zoom factor.

camera->setZoomFactor(3.0);

After capturing the raw data for a camera frame, the camera hardware and software performs various image processing tasks to produce the final image. This includes compensating for ambient light color, reducing noise, as well as making some other adjustments to the image.

You can control many of these processing steps through the Camera properties. For example, you can set the white balance (or color temperature) used for processing images:

camera->setWhiteBalanceMode(QCamera::WhiteBalanceFluorescent);

For more information on image processing of camera frames, see 攝像頭圖像處理 .

Most platforms require that the end-user grants permissions before a camera can be activated. It is therefore strongly recommended that application developers utilize the QCameraPermission class when working with cameras. The following is a short example that requests permissions from the end-user when the application starts, and then activates the camera if permissions are granted.

qApp->requestPermission(
    QCameraPermission{},
    [](const QPermission &permission) {
        if (permission.status() == Qt::PermissionStatus::Granted)
            camera->setActive(true);
    });

見攝像頭概述瞭解更多信息。

注意： On WebAssembly platform, due to it's asynchronous nature, QMediaDevices::videoInputsChanged () signal is emitted when the list of video inputs is ready. User permissions are required. Works only on secure https contexts.

成員類型文檔編製

enum QCamera:: Error

此枚舉保持最後錯誤代碼。

常量	值	描述
`QCamera::NoError`	`0`	沒有齣現錯誤。
`QCamera::CameraError`	`1`	有齣現錯誤。

enum QCamera:: ExposureMode

常量	值	描述
`QCamera::ExposureAuto`	`0`	自動模式。
`QCamera::ExposureManual`	`1`	手動模式。
`QCamera::ExposurePortrait`	`2`	肖象曝光模式。
`QCamera::ExposureNight`	`3`	夜間模式。
`QCamera::ExposureSports`	`4`	亮點曝光模式。
`QCamera::ExposureSnow`	`5`	Snow exposure mode.
`QCamera::ExposureBeach`	`6`	Beach exposure mode.
`QCamera::ExposureAction`	`7`	Action mode. Since 5.5
`QCamera::ExposureLandscape`	`8`	Landscape mode. Since 5.5
`QCamera::ExposureNightPortrait`	`9`	Night portrait mode. Since 5.5
`QCamera::ExposureTheatre`	`10`	Theatre mode. Since 5.5
`QCamera::ExposureSunset`	`11`	Sunset mode. Since 5.5
`QCamera::ExposureSteadyPhoto`	`12`	Steady photo mode. Since 5.5
`QCamera::ExposureFireworks`	`13`	Fireworks mode. Since 5.5
`QCamera::ExposureParty`	`14`	Party mode. Since 5.5
`QCamera::ExposureCandlelight`	`15`	Candlelight mode. Since 5.5
`QCamera::ExposureBarcode`	`16`	Barcode mode. Since 5.5

enum class QCamera:: Feature
flags QCamera:: Features

Describes a set of features supported by the camera. The returned value can be a combination of:

常量	值	描述
`QCamera::Feature::ColorTemperature`	`0x1`	The Camera supports setting a custom colorTemperature .
`QCamera::Feature::ExposureCompensation`	`0x2`	The Camera supports setting a custom exposureCompensation .
`QCamera::Feature::IsoSensitivity`	`0x4`	The Camera supports setting a custom isoSensitivity .
`QCamera::Feature::ManualExposureTime`	`0x8`	The Camera supports setting a manual exposure Time .
`QCamera::Feature::CustomFocusPoint`	`0x10`	The Camera supports setting a custom focus point .
`QCamera::Feature::FocusDistance`	`0x20`	The Camera supports setting the focusDistance 特性。

Features 類型是 typedef 對於 QFlags <Feature>. It stores an OR combination of Feature values.

enum QCamera:: FlashMode

常量	值	描述
`QCamera::FlashOff`	`0`	Flash is Off.
`QCamera::FlashOn`	`1`	Flash is On.
`QCamera::FlashAuto`	`2`	自動閃光。

enum QCamera:: FocusMode

常量	值	描述
`QCamera::FocusModeAuto`	`0`	Continuous auto focus mode.
`QCamera::FocusModeAutoNear`	`1`	Continuous auto focus mode on near objects.
`QCamera::FocusModeAutoFar`	`2`	Continuous auto focus mode on objects far away.
`QCamera::FocusModeHyperfocal`	`3`	Focus to hyperfocal distance, with the maximum depth of field achieved. All objects at distances from half of this distance out to infinity will be acceptably sharp.
`QCamera::FocusModeInfinity`	`4`	Focus strictly to infinity.
`QCamera::FocusModeManual`	`5`	Camera lens focus distance is locked according to focusDistance .

enum QCamera:: TorchMode

常量	值	描述
`QCamera::TorchOff`	`0`	Torch is Off.
`QCamera::TorchOn`	`1`	Torch is On.
`QCamera::TorchAuto`	`2`	Automatic torch.

enum QCamera:: WhiteBalanceMode

常量	值	描述
`QCamera::WhiteBalanceAuto`	`0`	Auto white balance mode.
`QCamera::WhiteBalanceManual`	`1`	Manual white balance. In this mode the white balance should be set with setColorTemperature ()
`QCamera::WhiteBalanceSunlight`	`2`	Sunlight white balance mode.
`QCamera::WhiteBalanceCloudy`	`3`	Cloudy white balance mode.
`QCamera::WhiteBalanceShade`	`4`	Shade white balance mode.
`QCamera::WhiteBalanceTungsten`	`5`	Tungsten (incandescent) white balance mode.
`QCamera::WhiteBalanceFluorescent`	`6`	Fluorescent white balance mode.
`QCamera::WhiteBalanceFlash`	`7`	Flash white balance mode.
`QCamera::WhiteBalanceSunset`	`8`	Sunset white balance mode.

特性文檔編製

active : bool

Describes whether the camera is currently active.

訪問函數：

bool	isActive () const
void	setActive (bool active )

通知程序信號：

void	activeChanged (bool)

cameraDevice : QCameraDevice

返迴 QCameraDevice object associated with this camera.

When switching camera devices, the QCamera 's capabilities are updated. Additionally, the QCamera 's control properties (such as focusMode , flashMode , focusDistance , zoomFactor ) are updated as follows:

If a property is supported on the new device, the property value is applied to the camera device.
If a property is supported but its range of valid values was changed, the property is clamped to the new range and applied to the camera device.
If the new camera device does not support a property, the property value is reset to default, and no changes are made to the camera device.

訪問函數：

QCameraDevice	cameraDevice () const
void	setCameraDevice (const QCameraDevice & cameraDevice )

通知程序信號：

void	cameraDeviceChanged ()

cameraFormat : QCameraFormat

Returns the camera format currently used by the camera.

注意： When using the FFMPEG backend on an Android target device if you request YUV420P format, you will receive either a fully planar 4:2:0 YUV420P or a semi-planar NV12/NV21. This depends on the codec implemented by the device OEM.

注意： On macOS, camera-devices are shared across multiple applications on the operating system. This means that another application may override the format set by this property. Application developers should account for receiving video frames that have a different resolution, pixel format and framerate than what is described by this property. This property does not change when the device's format is modified by another application. The format described by this property can be re-applied to the device by re-activating the QCamera .

訪問函數：

QCameraFormat	cameraFormat () const
void	setCameraFormat (const QCameraFormat & format )

通知程序信號：

void	cameraFormatChanged ()

另請參閱 QCameraDevice::videoFormats .

colorTemperature : int

Returns the current color temperature if the current white balance mode is WhiteBalanceManual . For other modes the return value is undefined.

訪問函數：

int	colorTemperature () const
void	setColorTemperature (int colorTemperature )

通知程序信號：

void	colorTemperatureChanged () const

customFocusPoint : QPointF

This property represents the position of the custom focus point, in relative frame coordinates: QPointF (0,0) points to the left top frame point, QPointF (0.5,0.5) points to the frame center.

You can check whether custom focus points are supported by querying supportedFeatures () with the Feature. CustomFocusPoint 標誌。

訪問函數：

QPointF	customFocusPoint () const
void	setCustomFocusPoint (const QPointF & point )

通知程序信號：

void	customFocusPointChanged ()

`[read-only]` error : const Error

Returns the error state of the camera.

訪問函數：

QCamera::Error error () const

通知程序信號：

void	errorChanged ()

另請參閱 QCamera::Error .

`[read-only]` errorString : const QString

Returns a human readable string describing a camera's error state.

訪問函數：

QString errorString () const

通知程序信號：

void	errorChanged ()

exposureCompensation : float

Exposure compensation in EV units.

Exposure compensation property allows to adjust the automatically calculated exposure.

訪問函數：

float	exposureCompensation () const
void	setExposureCompensation (float ev )

通知程序信號：

void	exposureCompensationChanged (float value )

exposureMode : QCamera::ExposureMode

This property holds the exposure mode being used.

訪問函數：

QCamera::ExposureMode	exposureMode () const
void	setExposureMode (QCamera::ExposureMode mode )

通知程序信號：

void	exposureModeChanged ()

另請參閱 QCamera::isExposureModeSupported .

`[read-only]` exposureTime : const float

Camera's exposure time in seconds.

訪問函數：

float exposureTime () const

通知程序信號：

void	exposureTimeChanged (float speed )

另請參閱 minimumExposureTime (), maximumExposureTime ()，和 setManualExposureTime ().

flashMode : QCamera::FlashMode

This property holds the flash mode being used.

Enables a certain flash mode if the camera has a flash.

Assigning an unsupported mode to this property has no effect.

This property only has an effect when capturing images using QImageCapture

訪問函數：

QCamera::FlashMode	flashMode () const
void	setFlashMode (QCamera::FlashMode mode )

通知程序信號：

void	flashModeChanged ()

另請參閱 QCamera::FlashMode , QCamera::isFlashModeSupported ，和 QCamera::isFlashReady .

`[read-only]` flashReady : const bool

Indicates if the flash is charged and ready to use.

訪問函數：

bool isFlashReady () const [見下文注意事項]

注意： 此函數可以被援引，通過元對象係統和從 QML。見 Q_INVOKABLE .

通知程序信號：

void	flashReady (bool ready )

focusDistance : float

This property defines the lens focus distance when the camera device works in manual focus mode. Valid values range from 0 to 1, where 0 is the closest possible focus distance, and 1 is the farthest. The farthest point is typically at infinity, but this may not be the case for all devices.

This property is applied to the device only when focusMode 被設為 FocusModeManual ，和 supportedFeatures includes the Feature::FocusDistance 標誌。

If you assign a value to this property while focusMode is not set to QCamera::FocusModeManual , the property stores the value but does not affect the device until QCamera::FocusModeManual is active.

Assigning a value outside the valid range [0, 1] has no effect on this property.

若 supportedFeatures does not include the FocusDistance flag, any attempt to set this property is ignored.

This property will not be updated by the camera when it is in an automatic focus mode.

默認值為 1。

訪問函數：

float	focusDistance () const
void	setFocusDistance (float d )

通知程序信號：

void	focusDistanceChanged (float)

focusMode : FocusMode

This property holds the current camera focus mode.

This property holds the value that controls focus mode for the camera device. In all autofocus modes, the camera device keeps focusing continuously.

To check whether the camera device supports a particular focus mode, pass the corresponding FocusMode value to the isFocusModeSupported function as a parameter. The function returns false if the focus mode value is not supported. Assigning an unsupported mode to this property has no effect.

If you set the focusMode property to QCamera::FocusModeManual , the lens locks to the focus according to focusDistance .

訪問函數：

QCamera::FocusMode	focusMode () const
void	setFocusMode (QCamera::FocusMode mode )

通知程序信號：

void	focusModeChanged ()

另請參閱 isFocusModeSupported ().

`[read-only]` focusPoint : const QPointF

Returns the point currently used by the auto focus system to focus onto.

訪問函數：

QPointF focusPoint () const

通知程序信號：

void	focusPointChanged ()

`[read-only]` isoSensitivity : const int

This property holds the sensor ISO sensitivity.

Describes the ISO sensitivity currently used by the camera.

訪問函數：

int	isoSensitivity () const

通知程序信號：

void	isoSensitivityChanged (int value )

另請參閱 setAutoIsoSensitivity () 和 setManualIsoSensitivity ().

manualExposureTime : float

Set the manual exposure time to seconds

訪問函數：

float	manualExposureTime () const
void	setManualExposureTime (float seconds )

通知程序信號：

void	manualExposureTimeChanged (float speed )

manualIsoSensitivity : int

Describes a manually set ISO sensitivity

Setting this property to -1 (the default), implies that the camera automatically adjusts the ISO sensitivity.

訪問函數：

int	manualIsoSensitivity () const
void	setManualIsoSensitivity (int iso )

通知程序信號：

void	manualIsoSensitivityChanged (int)

`[read-only]` maximumZoomFactor : const float

Returns the maximum zoom factor.

This will be 1.0 on cameras that do not support zooming.

訪問函數：

float maximumZoomFactor () const

通知程序信號：

void	maximumZoomFactorChanged (float)

`[read-only]` minimumZoomFactor : const float

Returns the minimum zoom factor.

This will be 1.0 on cameras that do not support zooming.

訪問函數：

float minimumZoomFactor () const

通知程序信號：

void	minimumZoomFactorChanged (float)

`[read-only]` supportedFeatures : const Features

Returns the features supported by this camera.

訪問函數：

QCamera::Features supportedFeatures () const

通知程序信號：

void	supportedFeaturesChanged ()

另請參閱 QCamera::Feature .

torchMode : QCamera::TorchMode

This property holds the torch mode being used.

A torch is a continuous source of light. It can be used during video recording in low light conditions. Enabling torch mode will usually override any currently set flash mode.

訪問函數：

QCamera::TorchMode	torchMode () const
void	setTorchMode (QCamera::TorchMode mode )

通知程序信號：

void	torchModeChanged ()

另請參閱 QCamera::TorchMode , QCamera::isTorchModeSupported ，和 QCamera::flashMode .

whiteBalanceMode : WhiteBalanceMode

Returns the white balance mode being used.

訪問函數：

QCamera::WhiteBalanceMode	whiteBalanceMode () const
void	setWhiteBalanceMode (QCamera::WhiteBalanceMode mode )

通知程序信號：

void	whiteBalanceModeChanged () const

zoomFactor : float

This property holds the current zoom factor.

Gets or sets the current zoom factor. Values will be clamped between minimumZoomFactor and maximumZoomFactor .

訪問函數：

float	zoomFactor () const
void	setZoomFactor (float factor )

通知程序信號：

void	zoomFactorChanged (float)

成員函數文檔編製

`[explicit]` QCamera:: QCamera ( QObject * parent = nullptr)

Construct a QCamera with a parent .

Selects the default camera on the system if more than one camera is available.

`[explicit]` QCamera:: QCamera ( QCameraDevice::Position position , QObject * parent = nullptr)

Construct a QCamera which uses a hardware camera located a the specified position .

For example on a mobile phone it can be used to easily choose between front-facing and back-facing cameras.

If no camera is available at the specified position or if position is QCameraDevice::UnspecifiedPosition , the default camera is used.

`[explicit]` QCamera:: QCamera (const QCameraDevice & cameraDevice , QObject * parent = nullptr)

Construct a QCamera from a camera description cameraDevice and parent .

`[override virtual noexcept]` QCamera:: ~QCamera ()

銷毀攝像頭對象。

QMediaCaptureSession *QCamera:: captureSession () const

Returns the capture session this camera is connected to, or a nullptr if the camera is not connected to a capture session.

使用 QMediaCaptureSession::setCamera () to connect the camera to a session.

`[signal]` void QCamera:: errorOccurred ( QCamera::Error error , const QString & errorString )

This signal is emitted when error state changes to error . A description of the error is provided as errorString .

`[signal]` void QCamera:: exposureCompensationChanged ( float value )

Signal emitted when the exposure compensation changes to value .

注意： 通知程序信號對於特性 exposureCompensation .

float QCamera:: exposureTime () const

Returns the current exposure time in seconds.

注意： Getter function for property exposureTime.

`[signal]` void QCamera:: exposureTimeChanged ( float speed )

Signals that a camera's exposure speed 已改變。

注意： 通知程序信號對於特性 exposureTime .

`[signal]` void QCamera:: flashReady ( bool ready )

Signal the flash ready status has changed.

注意： Notifier signal for property flashReady.

`[signal]` void QCamera:: focusModeChanged ()

Signals when the focusMode 改變。

注意： 通知程序信號對於特性 focusMode .

bool QCamera:: isActive () const

Returns true if the camera is currently active.

注意： getter 函數對於特性 active .

bool QCamera:: isAvailable () const

Returns true if the camera can be used.

`[invokable]` bool QCamera:: isExposureModeSupported ( QCamera::ExposureMode mode ) const

Returns true if the exposure mode is supported.

注意： 此函數可以被援引，通過元對象係統和從 QML。見 Q_INVOKABLE .

`[invokable]` bool QCamera:: isFlashModeSupported ( QCamera::FlashMode mode ) const

Returns true if the flash mode is supported.

注意： 此函數可以被援引，通過元對象係統和從 QML。見 Q_INVOKABLE .

`[invokable]` bool QCamera:: isFlashReady () const

Returns true if flash is charged.

注意： 此函數可以被援引，通過元對象係統和從 QML。見 Q_INVOKABLE .

注意： getter 函數對於特性 flashReady .

`[invokable]` bool QCamera:: isFocusModeSupported ( QCamera::FocusMode mode ) const

返迴 true if the focus mode is supported by the camera.

若 FocusModeManual is reported as supported, the feature Feature::FocusDistance is implied to be supported as well.

注意： 此函數可以被援引，通過元對象係統和從 QML。見 Q_INVOKABLE .

`[invokable]` bool QCamera:: isTorchModeSupported ( QCamera::TorchMode mode ) const

Returns true if the torch mode is supported.

注意： 此函數可以被援引，通過元對象係統和從 QML。見 Q_INVOKABLE .

`[invokable]` bool QCamera:: isWhiteBalanceModeSupported ( QCamera::WhiteBalanceMode mode ) const

Returns true if the white balance mode is supported.

注意： 此函數可以被援引，通過元對象係統和從 QML。見 Q_INVOKABLE .

`[signal]` void QCamera:: isoSensitivityChanged ( int value )

Signal emitted when sensitivity changes to value .

注意： 通知程序信號對於特性 isoSensitivity .

float QCamera:: manualExposureTime () const

Returns the manual exposure time in seconds, or -1 if the camera is using automatic exposure times.

注意： Getter function for property manualExposureTime.

另請參閱 setManualExposureTime ().

float QCamera:: maximumExposureTime () const

The maximal exposure time in seconds.

int QCamera:: maximumIsoSensitivity () const

Returns the maximum ISO sensitivity supported by the camera.

float QCamera:: minimumExposureTime () const

The minimal exposure time in seconds.

int QCamera:: minimumIsoSensitivity () const

Returns the minimum ISO sensitivity supported by the camera.

`[slot]` void QCamera:: setActive ( bool active )

Turns the camera on if active is true , or off if it's false .

注意： setter 函數對於特性 active .

另請參閱 isActive ().

`[slot]` void QCamera:: setAutoExposureTime ()

Use automatically calculated exposure time

`[slot]` void QCamera:: setAutoIsoSensitivity ()

Turn on auto sensitivity

void QCamera:: setCameraDevice (const QCameraDevice & cameraDevice )

Connects the camera object to the physical camera device described by cameraDevice . Using a default constructed QCameraDevice object as cameraDevice will connect the camera to the system default camera device.

If a property is supported on the new device, the property value is applied to the camera device.
If a property is supported but its range of valid values was changed, the property is clamped to the new range and applied to the camera device.
If the new camera device does not support a property, the property value is reset to default, and no changes are made to the camera device.

注意： setter 函數對於特性 cameraDevice .

另請參閱 cameraDevice ().

void QCamera:: setCameraFormat (const QCameraFormat & format )

Tells the camera to use the format described by format . This can be used to define a specific resolution and frame rate to be used for recording and image capture.

注意： setter 函數對於特性 cameraFormat .

另請參閱 cameraFormat ().

`[slot]` void QCamera:: setColorTemperature ( int colorTemperature )

Sets manual white balance to colorTemperature . This is used when whiteBalanceMode () 被設為 WhiteBalanceManual . The units are Kelvin.

Setting a color temperature will only have an effect if WhiteBalanceManual is supported. In this case, setting a temperature greater 0 will automatically set the white balance mode to WhiteBalanceManual . Setting the temperature to 0 will reset the white balance mode to WhiteBalanceAuto .

注意： setter 函數對於特性 colorTemperature .

另請參閱 colorTemperature ().

`[slot]` void QCamera:: setWhiteBalanceMode ( QCamera::WhiteBalanceMode mode )

Sets the white balance to mode .

注意： setter 函數對於特性 whiteBalanceMode .

另請參閱 whiteBalanceMode ().

void QCamera:: setZoomFactor ( float factor )

Zooms to a zoom factor factor at a rate of 1 factor per second.

注意： setter 函數對於特性 zoomFactor .

另請參閱 zoomFactor ().

`[slot]` void QCamera:: start ()

Starts the camera.

如同 setActive (true)。

If the camera can't be started for some reason, the errorOccurred () 信號發射。

`[slot]` void QCamera:: stop ()

Stops the camera. Same as setActive (false).

`[slot]` void QCamera:: zoomTo ( float factor , float rate )

Zooms to a zoom factor factor 使用 rate .

The rate is specified in powers of two per second. At a rate of 1 it would take 2 seconds to go from a zoom factor of 1 to 4.

注意： Using a specific rate is not supported on all cameras. If not supported, zooming will happen as fast as possible.

QCamera 類

公共類型

特性

公共函數

公共槽

信號

詳細描述

成員類型文檔編製

enum QCamera:: Error

enum QCamera:: ExposureMode

enum class QCamera:: Feature flags QCamera:: Features

enum QCamera:: FlashMode

enum QCamera:: FocusMode

enum QCamera:: TorchMode

enum QCamera:: WhiteBalanceMode

特性文檔編製

active : bool

cameraDevice : QCameraDevice

cameraFormat : QCameraFormat

colorTemperature : int

customFocusPoint : QPointF

[read-only] error : const Error

[read-only] errorString : const QString

exposureCompensation : float

exposureMode : QCamera::ExposureMode

[read-only] exposureTime : const float

flashMode : QCamera::FlashMode

[read-only] flashReady : const bool

focusDistance : float

focusMode : FocusMode

[read-only] focusPoint : const QPointF

[read-only] isoSensitivity : const int

manualExposureTime : float

manualIsoSensitivity : int

[read-only] maximumZoomFactor : const float

[read-only] minimumZoomFactor : const float

[read-only] supportedFeatures : const Features

torchMode : QCamera::TorchMode

whiteBalanceMode : WhiteBalanceMode

zoomFactor : float

成員函數文檔編製

[explicit] QCamera:: QCamera ( QObject * parent = nullptr)

[explicit] QCamera:: QCamera ( QCameraDevice::Position position , QObject * parent = nullptr)

[explicit] QCamera:: QCamera (const QCameraDevice & cameraDevice , QObject * parent = nullptr)

[override virtual noexcept] QCamera:: ~QCamera ()

QMediaCaptureSession *QCamera:: captureSession () const

[signal] void QCamera:: errorOccurred ( QCamera::Error error , const QString & errorString )

[signal] void QCamera:: exposureCompensationChanged ( float value )

float QCamera:: exposureTime () const

[signal] void QCamera:: exposureTimeChanged ( float speed )

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

[signal] void QCamera:: focusModeChanged ()

bool QCamera:: isActive () const

bool QCamera:: isAvailable () const

[invokable] bool QCamera:: isExposureModeSupported ( QCamera::ExposureMode mode ) const

[invokable] bool QCamera:: isFlashModeSupported ( QCamera::FlashMode mode ) const

[invokable] bool QCamera:: isFlashReady () const

[invokable] bool QCamera:: isFocusModeSupported ( QCamera::FocusMode mode ) const

[invokable] bool QCamera:: isTorchModeSupported ( QCamera::TorchMode mode ) const

[invokable] bool QCamera:: isWhiteBalanceModeSupported ( QCamera::WhiteBalanceMode mode ) const

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

float QCamera:: manualExposureTime () const

float QCamera:: maximumExposureTime () const

int QCamera:: maximumIsoSensitivity () const

float QCamera:: minimumExposureTime () const

int QCamera:: minimumIsoSensitivity () const

[slot] void QCamera:: setActive ( bool active )

[slot] void QCamera:: setAutoExposureTime ()

[slot] void QCamera:: setAutoIsoSensitivity ()

void QCamera:: setCameraDevice (const QCameraDevice & cameraDevice )

void QCamera:: setCameraFormat (const QCameraFormat & format )

[slot] void QCamera:: setColorTemperature ( int colorTemperature )

[slot] void QCamera:: setWhiteBalanceMode ( QCamera::WhiteBalanceMode mode )

void QCamera:: setZoomFactor ( float factor )

[slot] void QCamera:: start ()

[slot] void QCamera:: stop ()

[slot] void QCamera:: zoomTo ( float factor , float rate )

內容

enum class QCamera:: Feature
flags QCamera:: Features

`[read-only]` error : const Error

`[read-only]` errorString : const QString

`[read-only]` exposureTime : const float

`[read-only]` flashReady : const bool

`[read-only]` focusPoint : const QPointF

`[read-only]` isoSensitivity : const int

`[read-only]` maximumZoomFactor : const float

`[read-only]` minimumZoomFactor : const float

`[read-only]` supportedFeatures : const Features

`[explicit]` QCamera:: QCamera ( QObject * parent = nullptr)

`[explicit]` QCamera:: QCamera ( QCameraDevice::Position position , QObject * parent = nullptr)

`[explicit]` QCamera:: QCamera (const QCameraDevice & cameraDevice , QObject * parent = nullptr)

`[override virtual noexcept]` QCamera:: ~QCamera ()

`[signal]` void QCamera:: errorOccurred ( QCamera::Error error , const QString & errorString )

`[signal]` void QCamera:: exposureCompensationChanged ( float value )

`[signal]` void QCamera:: exposureTimeChanged ( float speed )

`[signal]` void QCamera:: flashReady ( bool ready )

`[signal]` void QCamera:: focusModeChanged ()

`[invokable]` bool QCamera:: isExposureModeSupported ( QCamera::ExposureMode mode ) const

`[invokable]` bool QCamera:: isFlashModeSupported ( QCamera::FlashMode mode ) const

`[invokable]` bool QCamera:: isFlashReady () const

`[invokable]` bool QCamera:: isFocusModeSupported ( QCamera::FocusMode mode ) const

`[invokable]` bool QCamera:: isTorchModeSupported ( QCamera::TorchMode mode ) const

`[invokable]` bool QCamera:: isWhiteBalanceModeSupported ( QCamera::WhiteBalanceMode mode ) const

`[signal]` void QCamera:: isoSensitivityChanged ( int value )

`[slot]` void QCamera:: setActive ( bool active )

`[slot]` void QCamera:: setAutoExposureTime ()

`[slot]` void QCamera:: setAutoIsoSensitivity ()

`[slot]` void QCamera:: setColorTemperature ( int colorTemperature )

`[slot]` void QCamera:: setWhiteBalanceMode ( QCamera::WhiteBalanceMode mode )

`[slot]` void QCamera:: start ()

`[slot]` void QCamera:: stop ()

`[slot]` void QCamera:: zoomTo ( float factor , float rate )