Joint MPEG-2 coding for multi-program broadcasting of pre-recorded video

The tradeoff between picture quality and bandwidth usage is one of the most prominent issues in the world of broadcasting. Since broadcasters are able to simultaneously transmit multiple streams in a channel, they face the challenge of guaranteeing a certain picture quality required by each of the video streams transmitted while maximizing the number of video streams carried in each channel. To address this problem, we developed an MPEG-2 based multi-program video coding system, suitable for digital T V broadcasting, video on demand, and high definition T V over broadcast satellite networks with limited bandwidth. The system can be easily implemented for commercial use in digital broadcasting applications. Compared to present broadcast systems and for the same level of guaranteed picture quality, our system greatly increases the number of video streams transmitted in each channel. As a result, a large number of transponders can be freed to carry real-time broadcasting. By switching from tape storage to video server technology, the need for numerous playback (VTR) systems at the headend is eliminated. In addition, the majority of the complete MPEG-2 encoders are replaced by much less complex MPEG-2 transcoders. The freeing of numerous transponders, the elimination of numerous playback systems, and the replacement of the complete MPEG-2 encoders with MPEG-2 transcoders provide a much more cost-effective solution for the broadcast stations.