A high quality digital HDTV codec

A digital video codec has been developed for the Zenith/AT&T HDTV (high-definition TV) system for terrestrial broadcast over NTSC taboo channels. The codec works on an image progressively scanned with 1575 scan lines every 1/30th of a second and achieves a compression ratio of approximately 50 to 1. The transparent image quality is achieved using motion-compensated transform coding coupled with a perceptual criterion to determine the quantization accuracy required for each transform coefficient. The combination of a sophisticated encoded video format and advanced bit error protection techniques results in a highly robust reception and decoding of the compressed video signal.<
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