IVMRMixerBitmap::UpdateAlphaBitmapParameters method (strmif.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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 UpdateAlphaBitmapParameters method changes the bitmap location, size and blending value.
Syntax
HRESULT UpdateAlphaBitmapParameters(
[in] PVMRALPHABITMAP pBmpParms
);
Parameters
[in] pBmpParms
A pointer to a VMRALPHABITMAP structure.
Return value
If the method succeeds, it returns S_OK. If it fails, it returns an error code.
Remarks
The filter graph must be running for the changes to take effect. This method does not change the bitmap image. If you specify a VMRALPHABITMAP structure with no destination or color key set, the bitmap disappears. This behavior is by design for backward compatibility and cannot be changed.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows XP [desktop apps only] |
| Minimum supported server | Windows Server 2003 [desktop apps only] |
| Target Platform | Windows |
| Header | strmif.h (include Dshow.h) |
| Library | Strmiids.lib |