The Digital Fact Book - Quantel

DDual linkThe bandwidth of SDI and HD-SDI links allow the transport of uncompressed 4:2:2 sampledvideo and embedded digital audio. Dual links are often used to carry larger requirements– such as video with key (4:2:2:4), RGB (4:4:4) and RGB with key (4:4:4:4). Dual link for SD isdefined in ITU-R/BT.799-2 and RP 175-1997. Dual link at HD is used for stereo3D and 50/60 P.A dual link is arranged to allow some meaningful monitoring of each of the two links withstandard equipment. So RGB is sent with Link A carrying full bandwidth G, half R and B(4:2:2). Link B is just half bandwidth R and B (0:2:2). RGB + Key is sent as (4:2:2) and (4:2:2).See also: 0:2:2, 4:2:2, HD-SDI, HSDL, SDI, Y Cr CbWebsite: www.itu.chDuplex(Full duplex) refers to communications that are simultaneously two-way (send and receive)– like the telephone. Those referred to as half-duplex switch between send and receive.DVThis digital VCR format was formed jointly as a co-operation between Hitachi, JVC, Sony,Matsushita, Mitsubishi, Philips, Sanyo, Sharp, Thomson and Toshiba. It uses 6.35 mm(quarter-inch) wide tape in a range of products to record 525/60 or 625/50 video forthe consumer (DV) and professional markets (Panasonic’s DVCPRO and Sony’s DVCAM).All recorders use digital intra-field DCT-based ‘DV’ compression (about 5:1) to record 8-bitcomponent digital video based on 13.5 MHz luminance sampling. The consumer versionsand DVCAM sample video at 4:1:1 (525/60) or 4:2:0 (625/50) video and provide two16-bit/48 or 44.1 kHz, or four 12-bit/32 kHz audio channels onto a 4-hour 30-minutestandard cassette (125 x 78 x 14.6 mm) or smaller 1-hour ‘mini’ cassette (66 x 48 x 12.2 mm).The data rate is 25 Mb/s. The professional DVCPRO models make use of DV’s hierarchicaldesign, being x2 and x4 versions of the basic 25 Mb/s version.DVCAM is Sony’s professional variant of DV which records 15-micron tracks on a metalevaporated (ME) tape. As stated, video sampling is 4:2:0 for 625/50 (PAL) and 4:1:1 for525/60 (NTSC). Audio is four 12-bit, 32 kHz channels, or two 16-bit 48 kHz channels.DVCPRO is Panasonic’s development of native DV which records 18-micron tracks ontometal particle tape. It uses native DV compression at 5:1 from a 4:1:1, 8-bit sampled source.There are 12 tracks per frame for 625/50 and 10 tracks per frame for 525/60, tape speedis 33.8 mm/s and the data rate 25 Mb/s. It includes two 16-bit digital audio channelssampled at 48 kHz and an analog cue track. Both linear (LTC) and Vertical Interval Timecode(VITC) are supported.72