Error resilient two-layer H.263-based codecs for a ATM environments

The introduction of new multi-media services and the enhancement of the exi sting services forced the existing networks to their performance limits. Mo st of the networks today face the problem of bandwidth limitation. ATM netw orks solve the problem of bandwidth bottleneck by the introduction of stati stical multiplexing and priority switching. Many video coders/decoders (cod ecs) have been designed to suit this new technology [1-6]. Some of these co decs are designed to increase the resilience of the codec to cell loss as w ell as the sharing ability of the assigned bandwidth by implementing variou s layering techniques. Other multi-media services designers prefer to imple ment cell concealment techniques at the decoder side to combat cell loss [7 ]. This paper presents new two-layer error resilient video codecs based on the classical TWIN-H,261 and the Inter-Enhance H,261 video codecs [2-4]. A study of the performance of the proposed codecs is included in this paper w ith a comparison with the other classical two-layer codecs in terms of the reconstructed image quality, the resilience to cell loss, the bit rate prod uced and the codec complexity. (C) 2001 Academic Press.