Chapter 3
SDI Configuration
Topics in this chapter
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Configuration: Encoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Configuration: Decoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Introduction
Serial Digital Interface, or SDI, is mainly used in the professional industry and is based on the principal standard for broadcast television and the motion picture industries. Reliable, flexible and cost-effective video transport is critical to the video transmission industry, which provides state-of-the-art transport services for broadcast networks, content producers, entertainment programmers, news agencies and sportscasters throughout the world. SDI provides users the best available video quality with virtually no latency.
The Serial Digital Interface Encoder is a module that plugs into the encoder card, allowing the broadcast industry standard 270 Mbps serial signal to be converted to MPEG-2. The Serial Digital Interface input module accepts the Society of Motion Picture and Television Engineers industry-standard, SMPTE 259M-C compliant signals at 270 Mbps. The standard specifies a Serial Digital Interface (SDI) for digital video equipment operating at either the 525-line, 60 Hz or 625-line, 50 Hz video standard. After VBrick's MPEG-2 conversion, the compressed video can be transported and utilized over a standard IP network.
The SDI module extracts AES/EBU or non-AES/EBU audio from Group 1 channels 1 – 4 from the incoming 270 Mbps data stream. These audio channels are embedded into the SDI video stream and occupy space in the horizontal and vertical blanking interval. These four channels are extracted into two SDI stereo streams of audio. SDI 1-2 contains the stereo channels 1 and 2 from Group 1 of the embedded audio. SDI 3-4 contains the stereo channels 3 and 4 from Group 1 of the embedded audio. The SDI hardware can select either channels 1 and 2, or channels 3 and 4 from the SDI stream. Audio embedded in Groups 2, 3, and 4 of the SDI stream will not be extracted. If desired, the user may bypass any embedded SDI audio and provide analog audio input at the VBrick encoder. The SDI input module is available with model numbers ending in –x101, –x111, –x102, –x112.
The Serial Digital Interface output module is similar to the SDI input module; however, the output module provides an SDI signal to the end-user. The SDI output module plugs into the decoder card, allowing MPEG-2 to be converted to the broadcast industry standard SMPTE 259M-C, 270 Mb/s serial signal, or SDI. The SDI output module operates at either the 525- line, 60 Hz or 625-line, 50 Hz video standard. The decoder module does not provide EDH, or Error Detect Handling.
The SDI output module multiplexes one group containing channels 1 and 2 of stereo (L/R) audio into the serial video stream. Also included is the "standard" implementation of channel status, provided for professional or broadcast use per AES3-1992 (r1997). The user may still utilize the analog video and audio available at the decoder output while simultaneously using
