QCamera 类

QCamera 类提供系统摄像头设备的接口。 更多...

头：	#include <QCamera>
CMake:	find_package(Qt6 REQUIRED COMPONENTS Multimedia) target_link_libraries(mytarget PRIVATE Qt6::Multimedia)
qmake:	QT += multimedia
实例化：	Camera
继承：	QObject

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公共类型

enum	Error { NoError, CameraError }
enum	ExposureMode { ExposureAuto, ExposureManual, ExposurePortrait, ExposureNight, ExposureSports, …, ExposureBarcode }
enum class	特征 { ColorTemperature, ExposureCompensation, IsoSensitivity, ManualExposureTime, CustomFocusPoint, FocusDistance }
flags	特征
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 : int manualIsoSensitivity : int maximumZoomFactor : const float minimumZoomFactor : const float supportedFeatures : const Features torchMode : QCamera::TorchMode whiteBalanceMode : WhiteBalanceMode zoomFactor : float

公共函数

	QCamera (QObject * parent = nullptr)
	QCamera (const QCameraDevice & cameraDevice , QObject * parent = nullptr)
	QCamera (QCameraDevice::Position position , QObject * parent = nullptr)
virtual	~QCamera ()
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 )

信号

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)

详细描述

QCamera 可以用于 QMediaCaptureSession 为视频录制和图像获取。

可以使用 QCameraDevice 列表可用摄像头并选取要使用的摄像头。

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. This also includes functionality such as a "Macro" mode for close up work (e.g. reading barcodes, or recognizing letters), or "touch to focus" - indicating an interesting area of the image for the hardware to attempt to focus on.

camera->setFocusPointMode(QCamera::FocusModeManual);
camera->setCustomFocusPoint(QPointF(0.25f, 0.75f)); // A point near the bottom left, 25% away from the corner, near that shiny vase
					

The minimumZoomFactor () 和 maximumZoomFactor () methods provide the range of supported zoom factors. The zoomTo () method 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 摄像头图像处理 .

见 摄像头概述 了解更多信息。

成员类型文档编制

enum QCamera:: Error

此枚举保持最后错误代码。

常量	值	描述
QCamera::NoError	0	没有出现错误。
QCamera::CameraError	1	有出现错误。

enum QCamera:: ExposureMode

常量	值	描述
QCamera::ExposureAuto	0	自动模式。
QCamera::ExposureManual	1	手动模式。
QCamera::ExposurePortrait	2	肖象曝光模式。
QCamera::ExposureNight	3	夜间模式。
QCamera::ExposureSports	4	亮点曝光模式。
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:: 特征
flags QCamera:: 特征

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。

The Features type is a typedef for 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	自动闪光。

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	Manual or fixed focus mode.

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.

特性文档编制

active : bool

Describes whether the camera is currently active.

访问函数：

bool	isActive () const
void	setActive (bool active )

通知程序信号：

void	activeChanged (bool)

cameraDevice : QCameraDevice

返回 QCameraDevice object associated with this camera.

访问函数：

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

通知程序信号：

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.

访问函数：

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

通知程序信号：

void	cameraFormatChanged ()

另请参阅 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.

访问函数：

int	colorTemperature () const
void	setColorTemperature (int colorTemperature )

通知程序信号：

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.

The custom focus point property is used only in FocusPointCustom focus mode.

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

访问函数：

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

通知程序信号：

void	customFocusPointChanged ()

[read-only] error : const Error

Returns the error state of the camera.

访问函数：

QCamera::Error

error () const

通知程序信号：

void	errorChanged ()

[read-only] errorString : const QString

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

访问函数：

QString

errorString () const

通知程序信号：

void	errorChanged ()

exposureCompensation : float

Exposure compensation in EV units.

Exposure compensation property allows to adjust the automatically calculated exposure.

访问函数：

float	exposureCompensation () const
void	setExposureCompensation (float ev )

通知程序信号：

void	exposureCompensationChanged (float value )

exposureMode : QCamera::ExposureMode

This property holds the exposure mode being used.

访问函数：

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

通知程序信号：

void	exposureModeChanged ()

另请参阅 QCamera::isExposureModeSupported .

[read-only] exposureTime : const float

Camera's exposure time in seconds.

访问函数：

float

exposureTime () const

通知程序信号：

void	exposureTimeChanged (float speed )

另请参阅 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.

访问函数：

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

通知程序信号：

void	flashModeChanged ()

另请参阅 QCamera::FlashMode , QCamera::isFlashModeSupported ，和 QCamera::isFlashReady .

[read-only] flashReady : const bool

Indicates if the flash is charged and ready to use.

访问函数：

bool

isFlashReady () const

[见下文注意事项]

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

通知程序信号：

void	flashReady (bool ready )

focusDistance : float

This property return an approximate focus distance of the camera. The value reported is between 0 and 1, 0 being the closest possible focus distance, 1 being as far away as possible. Note that 1 is often, but not always infinity.

Setting the focus distance will be ignored unless the focus mode is set to FocusModeManual .

访问函数：

float	focusDistance () const
void	setFocusDistance (float d )

通知程序信号：

void	focusDistanceChanged (float)

focusMode : FocusMode

This property holds the current camera focus mode.

Sets up different focus modes for the camera. All auto focus modes will focus continuously. Locking the focus is possible by setting the focus mode to FocusModeManual . This will keep the current focus and stop any automatic focusing.

访问函数：

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

通知程序信号：

void	focusModeChanged ()

另请参阅 isFocusModeSupported .

[read-only] focusPoint : const QPointF

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

访问函数：

QPointF

focusPoint () const

通知程序信号：

void	focusPointChanged ()

[read-only] isoSensitivity : const int

This property holds the sensor ISO sensitivity.

Describes the ISO sensitivity currently used by the camera.

访问函数：

int	isoSensitivity () const

通知程序信号：

void	isoSensitivityChanged (int value )

另请参阅 setAutoIsoSensitivity () 和 setManualIsoSensitivity ().

manualExposureTime : int

Set the manual exposure time to seconds

访问函数：

float	manualExposureTime () const
void	setManualExposureTime (float seconds )

通知程序信号：

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.

访问函数：

int	manualIsoSensitivity () const
void	setManualIsoSensitivity (int iso )

通知程序信号：

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.

访问函数：

float

maximumZoomFactor () const

通知程序信号：

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.

访问函数：

float

minimumZoomFactor () const

通知程序信号：

void	minimumZoomFactorChanged (float)

[read-only] supportedFeatures : const 特征

Returns the features supported by this camera.

访问函数：

QCamera::Features

supportedFeatures () const

通知程序信号：

void	supportedFeaturesChanged ()

另请参阅 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.

访问函数：

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

通知程序信号：

void	torchModeChanged ()

另请参阅 QCamera::TorchMode , QCamera::isTorchModeSupported ，和 QCamera::flashMode .

whiteBalanceMode : WhiteBalanceMode

Returns the white balance mode being used.

访问函数：

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

通知程序信号：

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 .

访问函数：

float	zoomFactor () const
void	setZoomFactor (float factor )

通知程序信号：

void	zoomFactorChanged (float)

成员函数文档编制

[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 (const QCameraDevice & cameraDevice , QObject * parent = nullptr)

Construct a QCamera from a camera description cameraDevice and parent .

[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.

[virtual noexcept] QCamera:: ~QCamera ()

销毁摄像头对象。

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： 通知程序信号对于特性 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 已改变。

注意： 通知程序信号对于特性 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 改变。

注意： 通知程序信号对于特性 focusMode .

bool QCamera:: isActive () const

Returns true if the camera is currently active.

注意： getter 函数对于特性 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： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

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

Returns true if the flash mode is supported.

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

[invokable] bool QCamera:: isFlashReady () const

Returns true if flash is charged.

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

注意： getter 函数对于特性 flashReady .

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

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

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

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

Returns true if the torch mode is supported.

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

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

Returns true if the white balance mode is supported.

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

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

Signal emitted when sensitivity changes to value .

注意： 通知程序信号对于特性 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.

另请参阅 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 函数对于特性 active .

另请参阅 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.

注意： setter 函数对于特性 cameraDevice .

另请参阅 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： 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： setter 函数对于特性 cameraFormat .

另请参阅 cameraFormat ().

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

Sets manual white balance to colorTemperature . This is used when whiteBalanceMode () 被设为 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 函数对于特性 colorTemperature .

另请参阅 colorTemperature ().

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

Sets the white balance to mode .

注意： setter 函数对于特性 whiteBalanceMode .

另请参阅 whiteBalanceMode ().

void QCamera:: setZoomFactor ( float factor )

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

注意： setter 函数对于特性 zoomFactor .

另请参阅 zoomFactor ().

[slot] void QCamera:: start ()

Starts the camera.

如同 setActive (true)。

If the camera can't be started for some reason, the errorOccurred () 信号发射。

[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.

内容

• 公共类型

• 特性

• 公共函数

• 公共槽

• 信号

• 详细描述