D3 video
Encyclopedia
Digital video
Digital video is a type of digital recording system that works by using a digital rather than an analog video signal.The terms camera, video camera, and camcorder are used interchangeably in this article.- History :...
videocassette format invented at NHK
NHK
NHK is Japan's national public broadcasting organization. NHK, which has always identified itself to its audiences by the English pronunciation of its initials, is a publicly owned corporation funded by viewers' payments of a television license fee....
, and introduced commercially by Panasonic
Panasonic
Panasonic is an international brand name for Japanese electric products manufacturer Panasonic Corporation, which was formerly known as Matsushita Electric Industrial Co., Ltd...
in 1991 to compete with Ampex
Ampex
Ampex is an American electronics company founded in 1944 by Alexander M. Poniatoff. The name AMPEX is an acronym, created by its founder, which stands for Alexander M. Poniatoff Excellence...
's D-2
D2 (video format)
D-2 is a professional digital recording videocassette format created by Ampex and other manufacturers through a standards group of the Society of Motion Picture and Television Engineers and introduced at the 1988 NAB convention as a lower-cost alternative to the D-1 format...
. It uses half-inch metal particle tape at 83.88 mm/s (compare to D-2's 19 mm and 131.7 mm/s). Like D-2, the video signal is sampled at four times the color subcarrier frequency, with eight bits per sample. Four channels of 48 kHz 16-20 bit PCM audio, and other ancillary data, are inserted during the vertical blanking interval. The aggregate net (error corrected) bitrate of the format is 143 Mbit/s, and because the codec is lossless, it has been used in data applications. Camcorder
Camcorder
A camcorder is an electronic device that combines a video camera and a video recorder into one unit. Equipment manufacturers do not seem to have strict guidelines for the term usage...
s were available which used this format, and are to date the only digital tape camcorders to use a lossless encoding scheme. The D-5
D5 HD
D-5 is a professional digital video format introduced by Panasonic in 1994. Like Sony's D-1 , it is an uncompressed digital component system , but uses the same half-inch tapes as Panasonic's digital composite D-3 format...
format, introduced in 1993 by Panasonic and presently (2006) marketed as D-5 HD
D5 HD
D-5 is a professional digital video format introduced by Panasonic in 1994. Like Sony's D-1 , it is an uncompressed digital component system , but uses the same half-inch tapes as Panasonic's digital composite D-3 format...
, uses the D-3 transport and tape running at roughly double D-3 speed. The D-3 transport in turn is derived from the MII
MII (videocassette format)
MII is a professional analog recording videocassette format developed by Panasonic in 1986 as their answer and competitive product to Sony's Betacam SP format...
transport. D-3/D-5 tapes come in small (161 mm X 96 mm X 25 mm), medium (212 mm X 124 mm X 25 mm), and large (296 mm X 167 mm X 25 mm) cassettes, with format-specific recognition holes. Maximum D-3 runtimes (in the Fujifilm lineup) are 50, 126, and 248 minutes respectively.