Dynamic rate shaping on MPEG-2 video streams for bandwidth saving on a faded satellite channel

In a previous work, we studied how to send a video stream over a noisy sate llite channel using the scalability features of the MPEG-2 standard. The ba se and the enhancement flows were sent with different levels of protection (bit and coding rates) in order to deal with the channel degradation. In th is paper, we add Dynamic Rate Shaping (DRS), thus obtaining a greater flexi bility in the choice of transmission parameters. In fact, it is possible to trim the required bandwidth in continuous mode in the working range, thus saving some bandwidth when keeping the video quality constant during changi ng fade conditions. The performances of DRS applied to both the non-scalabl e and the seal able MPEG-2 coded video streams are shown separately. An app lication of the techniques presented is discussed. and some criteria are gi ven for choosing the most suitable parameters, according to the service qua lity requirements.