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Multimedia Interface Reference

This chapter provides reference information about the interfaces that a filter has to implement to be used by the Multimedia library. Some of the interfaces are defined in the Addon Interface Library (the AO* interfaces), while others are defined in the Multimedia library (Media* interfaces). For a description of how to write a filter, see the Extending the Multimedia library chapter.

Interface	Description	Used in
`AODeConstructor`	Create and destroy interface for a filter	All filters
`AOStreamInspector`	A stream inspection interface	Any filter with a streaming input of raw data
`AOFormatInspector`	A format inspection interface	Decoders and writers working with formatted data
`AOExtInspector`	A file extension interface	Any reader that takes streaming input (not implemented by existing Multimedia filters)
`AOMimetypeInspector`	A mimetype inspection interface	Parsers
`AOResourceAccess`	A filter resource manipulation interface	Any filter that exposes resources
`MediaReader`	An input stream interface	Readers
`MediaWriter`	A stream writer interface	Writers that output to a streamer (such as the raw file or wave file writers)
`MediaInput`	Input channel interface	Filters with one or more input channels
`MediaOutput`	Output channel interface	Filters with one or more output channels
`MediaControl`	Playback control interface	Filters that need to respond to a Pause(), for example, frame-based filters that need to start at the beginning of a frame
`MediaSeeker`	Seek interface	Filters that need to respond to a Seek()
`MediaClock`	Clock synchronization interface	Writers. The library implements a default `MediaClock`, which is used by the existing audio writer filter.
`MediaBufferAllocator`	Buffer allocation interface	Any filter that uses custom buffer allocation. The library implements a default `MediaBufferAllocator`, which existing Multimedia filters use.

More information about the AO* interfaces can be found in the Addon Interfaces Library Reference.