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ICameraControl::put_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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 put_ZoomRelative method sets the camera's relative zoom. The relative zoom indicates the direction in which the lens is moving.

Syntax

HRESULT put_ZoomRelative(
  [in] long Value,
  [in] long Flags
);

Parameters

[in] Value

Specifies 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 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).

[in] Flags

Zero or more flags. See CameraControlFlags. If the CameraControl_Flags_Auto flag is used, the Value parameter is ignored and the camera sets the default value.

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