DV

DV is a relatively new form of video which encodes video onto tape in digital format with intraframe compression, making it straightforward to transfer the video onto computer for editing. DV tapes come in two formats: MiniDV and DV. They record digital video compressed by a DCT method at 25 Mb per second. As a computer file, this works out to roughly 3.5 MB per second.

The DV format uses "L-size" cassettes, while MiniDV cassettes are called "S-size". L-size cassettes can record up to two hours. Both MiniDV and DV tapes can come with a chip to store still photos; the chip can be used only if the camera in which it is placed supports the feature.

The DV codec is also used in videotape formats intended for advanced amateur and entry-level professional use. Sony devised the DVCAM[?] format, and Panasonic devised the DVC Pro format. These two formats differ from the DV format in terms of track width and tape type.

DVC Pro videotape machines can play DVCAM, DV tapes, and mini-DV tapes, with the mini-DV tapes requiring an adapter. DVCAM videotape machines can play DVCAM and MiniDV tapes, but not DV or DVC Pro. A DVCAM machine can also record in either format, but at its default setting will record only 40 minutes on a 60 minute miniDV tape, due to different rates of error correction.

Panasonic has further scaled the DV codec to cover HDTV applications with their DVC Pro 50 and DVC Pro HD formats. DVC Pro 50 doubles DVC Pro's tape recording speed, and hooks two DV codecs in parallel to record digital video at 50 Mb per second. DVC Pro HD increases the tape speed further, and uses four DV codecs in parallel to achieve 100 Mb per second.