Joint source-channel subband coding of images

This paper proposes a new adaptive source-channel coding scheme in the context of subband coding. We first express the total mean-squared distortion suffered by the source in terms of source and channel distortions of the subbands. We then minimize this total distortion by an appropriate choice of source and channel coding rates for the subbands. This corresponds to casting the conventional bit allocation problem in a joint source-channel coding context. The choice of rates depends on the state of the physical channel, modeled by a binary symmetric channel (BSC). We then use a finite state Markov model for a fading channel to generalize results obtained for the BSC. This results in a joint source-channel coding scheme that is optimized to the current state of a fading channel.