ICameraControl::get_ZoomRelative method (vidcap.h)

[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

The get_ZoomRelative method returns the camera's relative zoom. The relative zoom indicates the direction in which the lens is moving.

Syntax

HRESULT get_ZoomRelative(
  [out] long *pValue,
  [out] long *pFlags
);

Parameters

[out] pValue

Receives the relative zoom. The size of the value represents the desired zoom speed; a higher value represents a higher speed. To get the range of possible values, call ICameraControl::getRange_ZoomRelative.

Value Description
0 Stopped.
Positive value Zoom lens moving in the telephoto direction.
Negative value Zoom lens moving in the wide angle direction.

[out] pFlags

Receives one or more flags. See CameraControlFlags.

Return value

Returns an HRESULT value.

Requirements

Requirement Value
Minimum supported client Windows XP with SP2 [desktop apps only]
Minimum supported server Windows Server 2003 [desktop apps only]
Target Platform Windows
Header vidcap.h
Library Strmiids.lib

See also

Error and Success Codes

ICameraControl Interface