Video Decoding

DirectX VA permits one or more stages of the video decoding process to be divided between the host CPU and the video hardware accelerator. The accelerator executes the motion-compensated prediction (MCP), and may also execute the inverse discrete-cosine transform (IDCT) and the variable-length decoding (VLD) stages of the decoding process.

The DirectX VA API decodes a single video stream. Support of multiple video streams requires a separate DirectX VA session for each video stream (for example, a separate pair of output and input pins for the video decoder and acceleration driver to use in filter graph operation). For more information about a filter graph, see KS Minidriver Architecture.