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KSPROPERTY_CAMERACONTROL_PAN

User-mode clients use the KSPROPERTY_CAMERACONTROL_PAN property to get or set a camera's pan setting. This property is optional.

Usage Summary Table

Get Set Target Property descriptor type Property value type
Yes Yes Filter or node KSPROPERTY_CAMERACONTROL_S or KSPROPERTY_CAMERACONTROL_NODE_S LONG

The property value (operation data) is a LONG that specifies a camera's pan setting. This value is expressed in degrees.

Positive values indicate that the camera is rotated clockwise. Negative values indicate that the camera is rotated counterclockwise, as shown in the following illustration.

illustration showing camera pan values.

Every video capture minidriver that supports this property must define a range and default value for this property. The range for the device must be -180 through +180. The default value must be 0.

Caution

When writing or testing an app, you should be aware that in practice, some drivers define a custom range of pan values and custom step values that might not be based on typical units. Drivers might implement the pan control either physically or digitally.

Remarks

The Value member of the KSPROPERTY_CAMERACONTROL_S structure specifies the pan setting.

For cameras using the Platform DMFT for face-based 3A, the Pan control impacts the output window of the camera. The face coordinates produced by the Platform DMFT will be relative to this modified output window, so the camera is responsible for remapping the ROI coordinates to the camera's full field of view when the current field of view is modified by the Pan control. Depending on where the field of view modification occurs, the coordinate mapping may need to be bidirectional. For example, if the field of view modification is implemented in a component after the Platform DMFT in the driver chain, ROI coordinates provided by the application need to be mapped back to the full field of view before sending down to the camera and ROI coordinates calculated in the Platform DMFT need to be mapped to the modified field of view before being sent to an app requesting them.

Requirements

Header: ksmedia.h (include Ksmedia.h)

See also

KSPROPERTY

KSPROPERTY_CAMERACONTROL_S