DirectShow DV Filters

For DV capture from a camcorder, Windows provides the MSDV Driver. DirectShow also provides several filters that manipulate DV data:

• DV Splitter: Splits an interleaved DV stream into separate audio and video streams.
• DV Muxer: Combines audio and video streams into one interleaved stream.
• DV Video Decoder: Decodes a DV video stream into uncompressed video.
• DV Video Encoder: Encodes an uncompressed video stream into DV video.

These filters work in pairs, as shown in the following diagrams.

In the previous diagram, the DV Splitter splits the interleaved (type 1) stream into its component audio and video streams (type 2). The DV Video Decoder converts the type-2 video to uncompressed video.

In the next diagram, the DV Video Encoder converts uncompressed video to DV-encoded video. The DV Muxer combines the audio and video streams into a single interleaved (type-1) stream.

The DV Video Encoder supports the IDVEnc interface for setting the encoding standard (NTSC or PAL). The DV Video Decoder supports the IIPDVDec interface for setting the decoding resolution. The DV Splitter supports the IDVSplitter interface, for reducing the frame rate by half. (This can be useful if CPU resources are limited.)