DCT-Based Television Codec for DS3 Digital Transmission

An intrafield codec based on discrete cosine transform (DCT), and foreseen for transmission of NTSC video signals at DS3 line bit rate, is described. The codec is provided at the input (encoder) and output (decoder) with an interchangeable interface so that it can be used also for the 4:2:2 studio standard transmission. In the case of the NTSC video signal, after the analog-to-digital (A/D) conversion, the signal is split into three component-like signals, to which a two-dimensional 8 × 8 DCT is applied. The DCT-processed samples are then coded for transmission using a variable-length coding. A line buffer adapts the variable data rate, coming from the encoding procedure, to the line bit rate. To implement the more complex parts of the codec, several very large-scale integrated (VLSI) semicustom circuits have been designed.

Print ISSN

0036-1682

Published

1989-09

Content type

Original Research

DOI

10.5594/J02662