Format
D-1 stores uncompressed digitized component video, encoded at Y'CbCr 4:2:2 using the CCIR 601 raster format with 8 bits, along with PCM audio tracks as well as timecode on a 3/4 inch (19 mm) videocassette tape. The uncompressed component video used enormous bandwidth, 173 Mbit/sec (bit rate), for its time. The maximum record time on a D-1 tape is 94 minutes. The D-2 system soon followed, using composite video in order to lower the bandwidth needed.
D-1 resolution is 720 × 486 for NTSC systems and 720 × 576 for PAL systems; these resolutions come from Rec. 601 and are also used in DVD-Video and Standard-definition television. The D1 units are switchable between NTSC and PAL. Luma is sampled at 13.5 MHz and Chroma at 6.75 MHz with an overall data rate of 27 MHz. Sampling at 13.5 MHz was used as it is a common multiple of NTSC/PAL line rate (6x 2.5 MHz). The first input/output interface was a 25 pin parallel cable (SMPTE 125M) and later updated to serial digital interface on coaxial cable (SDI, SMPTE 259M, 75Ω coax, 270 MHz). Ancillary data can be put in H/V blanking intervals. Color space for Y’ B’-Y’ R’-Y’ is also defined in ITU Rec. 601 or Rec. 709 color space.
Panasonic's D-5 format has similar specifications, but was introduced much later.
Read more about this topic: D-1 (Sony)