KSPROPERTY_CAMERACONTROL_ZOOM_RELATIVE

The KSPROPERTY_CAMERACONTROL_ZOOM_RELATIVE property specifies the zoom status of the camera.

Usage Summary Table

GetSetTargetProperty Descriptor TypeProperty 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 relative zoom setting. The size of the value represents the desired zoom speed; a higher value represents a higher speed.

ValueDescription

0

Stop zoom lens motion.

Positive value

Start moving the zoom lens in the telephoto direction (initiate zoom-in).

Negative value

Start moving the zoom lens in the wide angle direction (initiate zoom-out).

 

Remarks

The Value member of the KSPROPERTY_CAMERACONTROL_NODE_S structure specifies the relative zoom.

Note that a particular device might support only a certain speed range. To determine the range of speeds supported by the device, an application can issue a KSPROPERTY_TYPE_BASICSUPPORT request. You can specify KSPROPERTY_TYPE_BASICSUPPORT in the Flags member of the KSPROPERTY_ITEM structure.

Some devices support only a single zoom speed. In this case, the sign of the Value member indicates whether the lens should zoom in or zoom out.

When making a set request, the client should supply one of the values in the preceding table in the Value member of the KSPROPERTY_CAMERACONTROL_NODE_S structure.

When making a get request, the client receives one of the values in the preceding table in the Value member of the KSPROPERTY_CAMERACONTROL_NODE_S structure. The value indicates the current zoom status of the camera.

Requirements

Version

Available for Windows Vista and later versions of the Windows operating system.

Header

Ksmedia.h (include Ksmedia.h)

See also

KSPROPERTY_CAMERACONTROL_NODE_S

 

 

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