QCameraControl Class
The QCameraControl class is an abstract base class for classes that control still cameras or video cameras. 更多...
| 头文件: | #include <QCameraControl> |
| qmake: | QT += multimedia |
| 基类: | QMediaControl |
公有类型
| enum | PropertyChangeType { CaptureMode, ImageEncodingSettings, VideoEncodingSettings, Viewfinder, ViewfinderSettings } |
公有函数
| ~QCameraControl() | |
| virtual bool | canChangeProperty(PropertyChangeType changeType, QCamera::Status status) const = 0 |
| virtual QCamera::CaptureModes | captureMode() const = 0 |
| virtual bool | isCaptureModeSupported(QCamera::CaptureModes mode) const = 0 |
| virtual void | setCaptureMode(QCamera::CaptureModes mode) = 0 |
| virtual void | setState(QCamera::State state) = 0 |
| virtual QCamera::State | state() const = 0 |
| virtual QCamera::Status | status() const = 0 |
- 32 个公有函数继承自 QObject
信号
| void | captureModeChanged(QCamera::CaptureModes mode) |
| void | error(int error, const QString &errorString) |
| void | stateChanged(QCamera::State state) |
| void | statusChanged(QCamera::Status status) |
- 2 个信号继承自 QObject
受保护的函数
| QCameraControl(QObject *parent = Q_NULLPTR) |
- 9 个受保护的函数继承自 QObject
Macros
其他继承的成员
详细描述
The QCameraControl class is an abstract base class for classes that control still cameras or video cameras.
This service is provided by a QMediaService object via QMediaService::control(). It is used by QCamera.
The interface name of QCameraControl is org.qt-project.qt.cameracontrol/5.0 as defined in QCameraControl_iid.
参见 QMediaService::requestControl() and QCamera.
成员类型
enum QCameraControl::PropertyChangeType
| Constant | Value | Description |
|---|---|---|
QCameraControl::CaptureMode | 1 | Indicates the capture mode is changed. |
QCameraControl::ImageEncodingSettings | 2 | Image encoder settings are changed, including resolution. |
QCameraControl::VideoEncodingSettings | 3 | Video encoder settings are changed, including audio, video and container settings. |
QCameraControl::Viewfinder | 4 | Viewfinder is changed. |
QCameraControl::ViewfinderSettings | 5 | Viewfinder settings are changed. |
成员函数
[protected] QCameraControl::QCameraControl(QObject *parent = Q_NULLPTR)
Constructs a camera control object with parent.
QCameraControl::~QCameraControl()
Destruct the camera control object.
[pure virtual] bool QCameraControl::canChangeProperty(PropertyChangeType changeType, QCamera::Status status) const
Returns true if backend can effectively apply changing camera properties of changeType type while the camera state is QCamera::Active and camera status matches status parameter.
If backend doesn't support applying this change in the active state, it will be stopped before the settings are changed and restarted after. Otherwise the backend should apply the change in the current state, with the camera status indicating the progress, if necessary.
[pure virtual] QCamera::CaptureModes QCameraControl::captureMode() const
Returns the current capture mode.
参见 setCaptureMode().
[signal] void QCameraControl::captureModeChanged(QCamera::CaptureModes mode)
Signal emitted when the camera capture mode changes.
[signal] void QCameraControl::error(int error, const QString &errorString)
Signal emitted when an error occurs with error code error and a description of the error errorString.
[pure virtual] bool QCameraControl::isCaptureModeSupported(QCamera::CaptureModes mode) const
Returns true if the capture mode is suported.
[pure virtual] void QCameraControl::setCaptureMode(QCamera::CaptureModes mode)
Sets the current capture mode.
The capture mode changes are synchronous and allowed in any camera state.
If the capture mode is changed while camera is active, it's recommended to change status to QCamera::LoadedStatus and start activating the camera in the next event loop with the status changed to QCamera::StartingStatus. This allows the capture settings to be applied before camera is started. Than change the status to QCamera::StartedStatus when the capture mode change is done.
参见 captureMode().
[pure virtual] void QCameraControl::setState(QCamera::State state)
Sets the camera state.
State changes are synchronous and indicate user intention, while camera status is used as a feedback mechanism to inform application about backend status. Status changes are reported asynchronously with QCameraControl::statusChanged() signal.
参见 state() and QCamera::State.
[pure virtual] QCamera::State QCameraControl::state() const
Returns the state of the camera service.
参见 setState() and QCamera::state.
[signal] void QCameraControl::stateChanged(QCamera::State state)
Signal emitted when the camera state changes.
In most cases the state chage is caused by QCameraControl::setState(), but if critical error has occurred the state changes to QCamera::UnloadedState.
[pure virtual] QCamera::Status QCameraControl::status() const
Returns the status of the camera service.
参见 QCamera::state.
[signal] void QCameraControl::statusChanged(QCamera::Status status)
Signal emitted when the camera status changes.
宏
QCameraControl_iid
org.qt-project.qt.cameracontrol/5.0
Defines the interface name of the QCameraControl class.