Given the context, this method retrieves whether scaling at the video port is possible.

HRESULT IsVPDecimationAllowed(
  AMVP_CONTEXT amvpContext,
  LPBOOL pbIsDecimationAllowed


  • amvpContext
    [in] Context (video or VBI) in which to query the VP decimation capability.
  • pbIsDecimationAllowed
    [out] Pointer to the retrieved value indicating whether decimation is allowed.

Return Values

Returns an HRESULT value that depends on the implementation of the interface. HRESULT can include one of the following standard constants, or other values not listed.

Value Description
E_FAIL Failure.
E_POINTER NULL pointer argument.
NOERROR No error.


The Overlay Mixer filter uses this function to determine whether the driver needs the mixer to decimate video data at its own discretion. This function can be especially useful in a capture with preview situation in which you would not want the VP mixer filter to perform any scaling at the video port.


DirectShow applications and DirectShow filters have different include file and link library requirements. See Setting Up the Build Environment for more information.

OS Versions: Windows CE 2.12 and later. Version 2.12 requires DXPAK 1.0 or later.

See Also

IVPConfig Interface

Last updated on Wednesday, April 13, 2005

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