Source Coding with Side Information at the Decoder and Uncertain Knowledge of the Correlation

Elsa Dupraz (1) , Aline Roumy (2) , Michel Kieffer (1, 3, 4)

1 L2S - Laboratoire des signaux et systèmes
2 Sirocco - Analysis representation, compression and communication of visual data
3 LTCI - Laboratoire Traitement et Communication de l'Information
4 IUF - Institut Universitaire de France

This paper considers the problem of lossless source coding with side information at the decoder, when the correlation model between the source and the side information is uncertain. Four parametrized models representing the correlation between the source and the side information are introduced. The uncertainty on the correlation appears through the lack of knowledge on the value of the parameters. For each model, we propose a practical coding scheme based on non-binary Low Density Parity Check Codes and able to deal with the parameter uncertainty. At the encoder, the choice of the coding rate results from an information theoretical analysis. Then we propose decoding algorithms that jointly estimate the source vector and the parameters. As the proposed decoder is based on the Expectation-Maximization algorithm, which is very sensitive to initialization, we also propose a method to produce first a coarse estimate of the parameters.

Domains: Computer Science [cs]; Information Theory [cs.IT]; Mathematics [math]; Information Theory [math.IT]

Elsa Dupraz, Aline Roumy, Michel Kieffer. Source Coding with Side Information at the Decoder and Uncertain Knowledge of the Correlation. IEEE Transactions on Communications, 2014, 62 (1), pp.269 - 279. ⟨10.1109/TCOMM.2013.120413.130102⟩. ⟨hal-00935847⟩