Variable bit rate coding for real-time video transmission in ATM networks

Future national and international telecommunication networks are headed towards using ATM (asynchronous transport multiplexing) technology. ATM technology allows seamless integration between different traffic types such as voice, video and data on a single network and also between customer premises´ equipment and common carriers´ networks. Unlike the current telephone networks, the ATM network provides virtual connections that have variable bandwidth and variable path delay between a sender and a receiver. Although ATM networks do support constant bandwidth channel as one of the traffic classes, using virtual connections as variable bandwidth pipes for video traffic is more attractive for reasons of efficiency in network usage and video quality. In this paper, we show that it is feasible to use congestion signals from networks as a feedback to the encoder and achieve very good perceptual quality for real-time video transmissions