[Component Video] [Composite Video]
[DisplayPort] [Monitor Buses] [RS-170]
[SCART] [SDI] [S-Video]
Serial digital interface
Serial digital interface [SDI] standard is based on a 270 Mbps
transfer rate, over a single 75 ohm coaxial cable [BNC connector], up to
600 feet. Serial Digital Interface is a [standard definition] digital
broadcast television standard providing a lossless digital encoding of
standard NTSC and PAL formats [with embedded audio]. SDI is used in
Television stations, cable channels, and professional production
Equipment. SDI provides a method for transmitting uncompressed digital
video, audio and other data between video devices.
SDI is described in
ITU R BT 601 standard for interface of component digital video. SDI is
defined in SMPTE259M and ITU-R BT.656 standards. SMPTE259M defines four
standard bit rates from 143Mbps to 360Mbps [ 270Mps is common]. SMPTE
344M adds a 540Mbps bit rate. One component of luminance (with 720
samples per line), and two of color (each with 360 samples per line).
There are either 10 or 8 bits per sample [scrambled, polarity independent
interface, with common scrambling for both component ITU-R 601 and
composite digital video and four channels of (embedded) digital audio].
The SDI bit stream is encoded using a pseudo-random scramble followed by a
a NRZ-to NRZI conversion. The scramble code is x9+
x4+1. The original 8-bit SDI format was based on CCIR-601, the
new 10-bit version is called SDTI [Serial Digital Transport
Serial digital data interface (SDDI) is a way of compressing digital
video for use on SDI-based equipment from Sony.
SDDI is now incorporated
into Serial digital transport interface.
Serial Digital Interface Cable; 75 Ohm Coax
75 Ohm Shielded Coax
NTSC [National Television System Committee] is used in US [and
PAL [Phase Alternation by Line] is used outside the US
.... M-PAL [Phase Alternation by Line] is used outside the US
.... N-PAL [Phase Alternation by Line] is used outside the
SECAM [Sequential Color with Memory] is used outside the US
Although the graphic indicates a RG58 or RG59 coax, the point is to show a single shielded coax cable.
© 1998 - 2012 All rights reserved Leroy Davis