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ICameraControl::put_ZoomRelative

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Microsoft DirectShow 9.0

ICameraControl::put_ZoomRelative

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

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(
  long  Value,
  long  Flags
);

Parameters

Value

[in]  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).

Flags

[in]  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 Values

Returns an HRESULT value.

Requirements

Header: Include Vidcap.h.

Library: Use Strmiids.lib.

See Also