Scalable digital television system

摘要

A scalable digital television system provides enhanced flexibility for program delivery to pay television subscribers. The system provides from one to sixteen audio/video programs to be delivered within the normal 6 MHz television bandwidth commonly referred to as a channel. Received analog television programs are sampled and converted to digital signals. The digital bitstreams are then processed to remove redundant information using the MPEG industry standard algorithms. The amount of redundant information removed determines the compression ratio for that program. The compression ratio of each program is independently programmable.