 Important: |
|---|
| This is retired content. This content is outdated and is no longer being maintained. It is provided as a courtesy for individuals who are still using these technologies. This content may contain URLs that were valid when originally published, but now link to sites or pages that no longer exist. |
A version of this page is also available for
4/8/2010
The base classes implement CBaseOutputPin::DecideAllocatorto let the output pin automatically use the downstream pin's allocator. One of the most common alterations in the derived class is to force the use of an object's own allocator (or one from an upstream filter).
In the DirectShow model, a source filter pushes media samples onto the next filter and requires its own allocator.
For example, if you write a transform-inplace filter and insert it between a source filter and a decompressor filter, the transform filter must present the source filter's allocator to the decompressor. Therefore, you must override the CBaseOutputPin::DecideAllocatormember function.