IAMWMBufferPassCallback interface (dshowasf.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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 IAMWMBufferPassCallback interface is provided for advanced scenarios in which applications need access to an INSSBuffer3 sample before it is passed downstream for further processing. Use this technique to set or retrieve data unit extensions such as the SMPTE time code for each sample. One common use for this interface is to force key-frame insertion in a variable bit rate video stream during file writing. To do this, you must set the cleanpoint property on individual INSSBuffer3 samples. This interface is implemented by applications and called by the WM ASF Writer or WM ASF Reader filter each time a new sample is delivered to the filter.
Inheritance
The IAMWMBufferPassCallback interface inherits from the IUnknown interface. IAMWMBufferPassCallback also has these types of members:
Methods
The IAMWMBufferPassCallback interface has these methods.
| IAMWMBufferPassCallback::Notify The Notify method is called by the pin for each buffer that is delivered during streaming. |
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Requires Dshowasf.h, Windows Media Format 9 Series SDK, or later versions of the SDK |
| Target Platform | Windows |
| Header | dshowasf.h |