Joint video encoding in DVB/ATSC multi-program transmission: MPEG-2 vs. H.264/AVC bitrate control

The main constrains in DVB/ATSC systems are limited bandwidths of available broadcasting channels. Obviously, providers want to broadcast as many video programs as possible with the best possible quality of service. However, the picture quality of encoded video is inversely proportional to the compression factor. In addition, the bandwidth required to broadcast an individual video program with high quality depends on the nature of the contents and it varies in time. A more uniform picture quality and a more efficient utilization of channel capacity are achieved using joint video encoding in multiprogram transmission. The objective of joint rate control is to dynamically distribute the channel capacity among programs according to their respective complexities. More existing approaches are based on MPEG-2 standard. This paper presents a framework which allows the comparison MPEG-2 vs. H.264 standard in joint coding of multiple programs. Operational encoder control and optimized bitrate allocation in standard simulation models are explained in-depth. It is shown experimentally that joint bitrate control can keep almost the user-required picture quality among multiple programs in comparison to an independent encoding.