Optimal VLC sequence decoding exploiting additional video stream properties

Joint source-channel decoding of variable length codes (VLC) for image and video streaming transmission over unreliable links, such as wireless networks, is a subject of increasing interest. This paper proposes an optimum maximum likelihood (ML) decoder of VLC sequences which exploits additional inherent redundancy in the source information, namely: (i) the correlation between bits, inside a VLC codeword; as well as (ii) the correlation between VLC codewords of a VLC sequence unit (e.g. corresponding to one image block). Performance results for improving video decoding over AWGN channels are then presented and compared to the prefix-based decoder as well as the recently proposed VLC decoders.