IAMWMBufferPass Interface
| Microsoft DirectShow 9.0 |
IAMWMBufferPass Interface
The IAMWMBufferPass interface is implemented on the output pins of the WM ASF Reader and the input pins of the WM ASF Writer. Applications can use this interface to get or set properties on individual samples in an ASF stream. Applications can also use it to get or set data unit extensions. To use this interface, implement the IAMWMBufferPassCallback interface in your application. Then call IAMWMBufferPass::SetNotify on the filter's pin with a pointer to the callback interface.
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 WM_SampleExtensionGUID_OutputCleanPoint property using the INSSBuffer3 interface on the sample. For more information about sample extensions, see the Windows Media Format SDK documentation.
In addition to the methods inherited from IUnknown, the IAMWMBufferPass interface exposes the following method.
| Method | Description |
| SetNotify | Sets an application-defined callback on the filter. |
Requirements
Header: Include Dshowasf.h. Requires Windows Media Format 9 Series or later.
Library: None.
See Also