Multiple description source coding with no excess marginal rate
Zhen Zhang, Thomas Berger · IEEE Transactions on Information Theory · 1995
Multiple description source coding concerns situations in which the transmission of the source information is distributed over two data streams at rates R/sub 1/ and R/sub 2/, respectively. When both data streams are received, the decoder uses the combined data at rate R/sub 1/+R/sub 2/ to reconstruct the source information with average distortion d/sub 0/. If a communication breakdown prevents one of the data streams from reaching the receiver, the decoder has to base its reconstruction solely on the available data at rate either R/sub 1/ or R/sub 2/. This results in a higher distortion of either d/sub 1/ or d/sub 2/, respectively. The region /spl Rscr/ of all achievable quintuples (R/sub 1/, R/sub 2/, d/sub 0/, d/sub 1/, d/sub 2/) has been determined in the so-called "no excess rate" sum case defined by imposing the requirement R/sub 1/+R/sub 2/=R(d/sub 0/), where R(/spl middot/) is the rate-distortion function of the source. The case with excess rate sum, characterized by R/sub 1/+R/sub 2/>R(d/sub 0/), is challenging. We study in this paper a special case of it in which the requirements R/sub t/=R(d/sub t/), t=1, 2, are imposed; we refer to this as the "no excess marginal rate" case. The lower and upper bounds on d/sub 0/ we obtain are separated by only a tiny gap when evaluated for a binary equiprobable source and the Hamming distortion measure.>