IVMRDeinterlaceControl::GetNumberOfDeinterlaceModes method (strmif.h)

Article
07/27/2023

[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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 GetNumberOfDeinterlaceModes method retrieves the deinterlacing modes available to the VMR for the specified video format.

Syntax

HRESULT GetNumberOfDeinterlaceModes(
  [in]      VMRVideoDesc *lpVideoDescription,
  [in, out] LPDWORD      lpdwNumDeinterlaceModes,
  [out]     LPGUID       lpDeinterlaceModes
);

Parameters

[in] lpVideoDescription

Pointer to a VMRVideoDesc structure that describes the video.

[in, out] lpdwNumDeinterlaceModes

Pointer to a DWORD value. On input, this value specifies the size of the array given in lpDeinterlaceModes. On output, it receives number of GUIDs the method copied into the array.

[out] lpDeinterlaceModes

Address of an array allocated by caller. The method fills the array with GUID values. To determine the size of the array that is needed, set this parameter to NULL and check the value returned in lpdwNumDeinterlaceModes.

Return value

Returns an HRESULT value. Possible values include the following:

Return code	Description
E_POINTER	NULL pointer argument.
S_OK	Success
VFW_E_VMR_NOT_IN_MIXER_MODE	The VMR is not in mixer mode.
VFW_E_DDRAW_CAPS_NOT_SUITABLE	The video card does not support hardware deinterlacing.

Remarks

This method returns an array of GUIDs, where each GUID represents a deinterlacing mode that is supported in hardware by the graphics device driver. The array is sorted by quality, so the first entry represents the best quality, the second entry represents the next best quality, and so forth.

All drivers are required to support the following mode:

GUID	Description
DXVA_DeinterlaceBobDevice	Bob mode

Drivers can support additional modes and should define their own GUIDs to identify them. For each returned mode, call the IVMRDeinterlaceControl::GetDeinterlaceModeCaps method to get information about that mode.

Requirements

Requirement	Value
Minimum supported client	Windows XP with SP1 [desktop apps only]
Minimum supported server	Windows Server 2003 [desktop apps only]
Target Platform	Windows
Header	strmif.h (include Dshow.h)
Library	Strmiids.lib