IVideoFrameStep::CanStep 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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 CanStep method determines the stepping capabilities of the specified filter.
Syntax
HRESULT CanStep(
long bMultiple,
IUnknown *pStepObject
);
Parameters
bMultiple
If bMultiple is zero and the method returns S_OK, the graph can step one frame at a time. If bMultiple if greater than zero and the method returns S_OK, the graph can step bMultiple frames at a time.
pStepObject
Pointer to an interface on the filter that will control the stepping operation. Specify NULL to perform frame stepping using the renderer filter in the graph. If the graph includes a custom filter that implements the frame stepping, then pStepObject should specify that filter's IBaseFilter interface.
Return value
Returns S_OK if the object can step or E_INVALIDARG if pStepObject 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 |