IVMRMixerBitmap::SetAlphaBitmap 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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 SetAlphaBitmap method specifies a new bitmap image and the source location of the bitmap and how and where it should be rendered on the destination rectangle.
Syntax
HRESULT SetAlphaBitmap(
[in] const VMRALPHABITMAP *pBmpParms
);
Parameters
[in] pBmpParms
A pointer to a VMRALPHABITMAP structure that contains information about the bitmap.
Return value
If the method succeeds, it returns S_OK. If it fails, it returns an error code.
| Return code | Description |
|---|---|
|
pBmpParms is NULL. |
|
Invalid argument. See Remarks. |
|
Could not create a destination DC or DIBSection for the bitmap. |
|
BitBlt to bitmap surface failed. |
Remarks
To remove the bitmap, set the VMRALPHABITMAP structure and call SetAlphaBitmap again.
The method might return E_INVALIDARG for several reasons:
-
[VMRALPHABITMAP](/windows/desktop/api/strmif/ns-strmif-vmralphabitmap) structure contains an invalid combination of flags.
[VMRALPHABITMAP](/windows/desktop/api/strmif/ns-strmif-vmralphabitmap) structure does not specify a valid HDC or DirectDraw surface.
- The value of fAlpha is invalid.
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 |
See also
IVMRMixerBitmap::GetAlphaBitmapParameters