H261 AND H263-BASED PROGRAMABLE VIDEO TRANSCEIVERS
Peter Cherriman, Lajos Hanzo · ePrints Soton (University of Southampton) · 1996
The video quality versus bitrate performance of the H.261 and H.268codecs is characterised and a bitrate control algorithm is proposed in order to maintain a selectable near-constant video bitrate. The source codecs are operated at four different bitrates, which result in a constant symbol rate after error correction coding. This system constellation allowed us to maintain a constant video user bandwidth requirement, but benefit from improving channel conditions in terms of better video quality, when invoking more bandwidth efficient modem schemes ranging from 1 to 6 bits per symbol.