A practical algorithm for distributed source coding based on continuous-valued syndromes

Recent advances in video coding are based on the principles of distributed source coding to both relax the inherent complexity of classical encoding algorithms and offer robustness against transmission errors. Several practical frameworks for distributed source coding take advantage of channel coding principles to encode a suitably pre-quantized version of the source. In this paper, we present an alternative two-step approach for the problem of coding a source which is correlated with another one that is available only at the decoder. First, based on the correlation of the side information, a continuous-valued syndrome is computed. Then, according to the given rate-constraint, the syndrome is encoded and transmitted as in classical source coding. The great flexibility of the coding system is confirmed by the simulation results: for source coding of i.i.d. Gaussian sources, the performance is always within 4 dB from the Wyner-Ziv bound, for a wide range of side information correlations and target bit-rates.