QCameraInfo ¶

概要 ¶

详细描述 ¶

QCameraInfo lets you query for camera devices that are currently available on the system.

静态函数 defaultCamera() and availableCameras() provide you a list of all available cameras.

This example prints the name of all available cameras:

const QList<QCameraInfo> cameras = QCameraInfo::availableCameras();
for (const QCameraInfo &cameraInfo : cameras)
    qDebug() << cameraInfo.deviceName();
											

A QCameraInfo can be used to construct a QCamera . The following example instantiates a QCamera whose camera device is named ‘mycamera’:

const QList<QCameraInfo> cameras = QCameraInfo::availableCameras();
for (const QCameraInfo &cameraInfo : cameras) {
    if (cameraInfo.deviceName() == "mycamera")
        camera = new QCamera(cameraInfo);
}
											

还可以使用 QCameraInfo to get general information about a camera device such as description, physical position on the system, or camera sensor orientation.

QCamera myCamera;
QCameraInfo cameraInfo(myCamera);
if (cameraInfo.position() == QCamera::FrontFace)
    qDebug() << "The camera is on the front face of the hardware system.";
else if (cameraInfo.position() == QCamera::BackFace)
    qDebug() << "The camera is on the back face of the hardware system.";
qDebug() << "The camera sensor orientation is " << cameraInfo.orientation() << " degrees.";
											

另请参阅

QCamera

class QCameraInfo ( [ name=QByteArray() ] ) ¶

QCameraInfo(camera)

QCameraInfo(other)

参数

• camera – QCamera

• name – QByteArray

• other – QCameraInfo

static PySide2.QtMultimedia.QCameraInfo. availableCameras ( [ position=QCamera.UnspecifiedPosition ] ) ¶

参数

position – Position

返回类型

Returns a list of available cameras on the system which are located at position .

若 position is not specified or if the value is UnspecifiedPosition , a list of all available cameras will be returned.

static PySide2.QtMultimedia.QCameraInfo. defaultCamera ( ) ¶

返回类型

QCameraInfo

Returns the default camera on the system.

The returned object should be checked using isNull() before being used, in case there is no default camera or no cameras at all.

另请参阅

availableCameras()

PySide2.QtMultimedia.QCameraInfo. description ( ) ¶

返回类型

unicode

Returns the human-readable description of the camera.

PySide2.QtMultimedia.QCameraInfo. deviceName ( ) ¶

返回类型

unicode

Returns the device name of the camera

This is a unique ID to identify the camera and may not be human-readable.

PySide2.QtMultimedia.QCameraInfo. isNull ( ) ¶

返回类型

bool

返回 true，若此 QCameraInfo is null or invalid.

PySide2.QtMultimedia.QCameraInfo. __ne__ ( other ) ¶

参数

other – QCameraInfo

返回类型

bool

返回 true，若此 QCameraInfo is different from other .

PySide2.QtMultimedia.QCameraInfo. __eq__ ( other ) ¶

参数

other – QCameraInfo

返回类型

bool

返回 true，若此 QCameraInfo 等于 other .

PySide2.QtMultimedia.QCameraInfo. orientation ( ) ¶

返回类型

int

Returns the physical orientation of the camera sensor.

The value is the orientation angle (clockwise, in steps of 90 degrees) of the camera sensor in relation to the display in its natural orientation.

You can show the camera image in the correct orientation by rotating it by this value in the anti-clockwise direction.

For example, suppose a mobile device which is naturally in portrait orientation. The back-facing camera is mounted in landscape. If the top side of the camera sensor is aligned with the right edge of the screen in natural orientation, the value should be 270. If the top side of a front-facing camera sensor is aligned with the right of the screen, the value should be 90.

PySide2.QtMultimedia.QCameraInfo. position ( ) ¶

返回类型

Position

Returns the physical position of the camera on the hardware system.