IMediaFilter::Run 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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 Run method runs the filter.
Syntax
HRESULT Run(
REFERENCE_TIME tStart
);
Parameters
tStart
Reference time corresponding to stream time 0.
Return value
Returns an HRESULT value. Possible values include those shown in the following table.
| Return code | Description |
|---|---|
|
Transition is not complete. |
|
Success. Transition is complete. |
Remarks
When a filter is running, it can receive, process, and deliver samples. Source filters generate new samples, and renderer filters render them.
The state transition might be asynchronous. If the method returns before the transition completes, the return value is S_FALSE.
Stream time is calculated as the current reference time minus tStart. To calculate when a media sample should be rendered, the renderer compares the time stamp with the current stream time. Thus, a media sample with a time stamp of zero should be rendered at time tStart. For more information, see Time and Clocks in DirectShow.
When an application calls the IMediaControl::Run method, the Filter Graph Manager calls IMediaFilter::Run on each filter. It sets the value of tStart slightly in the future, to account for graph latency.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 2000 Professional [desktop apps only] |
| Minimum supported server | Windows 2000 Server [desktop apps only] |
| Target Platform | Windows |
| Header | strmif.h (include Dshow.h) |
| Library | Strmiids.lib |