DV stands for Digital Video - video captured to a PC from a digital camcorder.
There are two methods of storing DV video data, that is, type-1 and type-2. Both are stored usually in AVI files. Any DV stored as type-1 cannot be used with VfW-based editors. Microsoft provides DV encoder and decoder filters for DirectShow only, and will not provide support for encoding or decoding DV video data for VfW.
DV Type-1 Method
The native DV interleaved stream that is produced and consumed in I/O with a DV device contains DV compressed video and pulse code modulated (PCM) audio data. This single interleaved stream can be stored in an AVI file as "ivas" stream (for interleaved video/audio stream). Microsoft refers to this format as a type-1 DV AVI file.
Because the type-1 format stores data as a single AVI stream, type-1 DV AVI files are not compatible with VfW. DirectShow, however, easily handles type-1 data streams by routing the streams to a DV Splitter filter that produces a DV-encoded video stream and one or more PCM audio streams for playback or subsequent processing.
DV Type-2 Method
Interleaved DV data can also be split into a single video stream and one to four audio streams within an AVI file. Microsoft refers to this format of storing DV data as type-2. This format has the advantage of being backward compatible with VfW, because it contains a standard video stream and at least one standard audio stream.
The type-2 file format requires a small amount of additional processing to split and multiplex the DV stream during the functions of capture and transmit to IEEE 1394 DV devices.
'Digital Video (DV)' is a video format launched in 1996, and, in its smaller tape form factor MiniDV, has since become one of the standards for consumer and semiprofessional video production. The DV specification (originally known as the Blue Book, current official name IEC 61834) defines both the codec and the tape format. Features include intraframe compression for uncomplicated editing, a standard interface for transfer to non-linear editing systems (IEEE 1394/FireWire), and good video quality, especially compared to earlier consumer analog formats such as 8 mm, Hi-8 and VHS-C. DV now enables filmmakers to produce movies inexpensively, associated with no-budget cinema.
There have been some variants on the DV standard, most notably the more professional DVCAM and DVCPRO standards by Sony and Panasonic, respectively. Also, there is a recent high-definition version called HDV, which is rather different on a technical level since it only uses the DV and MiniDV tape form factor, but MPEG-2 for compression.