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ICameraControl::get_ZoomRelative

 
Microsoft DirectShow 9.0

ICameraControl::get_ZoomRelative

This topic applies only to Windows XP Service Pack 2 and later.

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(
  long*  pValue,
  long*  pFlags
);

Parameters

pValue

[out]   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.

pFlags

[out]  Receives one or more flags. See CameraControlFlags.

Return Values

Returns an HRESULT value.

Requirements

Header: Include Vidcap.h.

Library: Use Strmiids.lib.

See Also