Multiple Descriptions with Side Informations Also Known At the Encoder

We propose a new scheme of multiple descriptions with side information (SI). The two side decoders of the system use two different SI streams. Both SI streams are available to the central decoder and to the encoder. We give an inner bound for this system for general source and SI. The tight bound is obtained for the quadratic Gaussian case. This result is compared with our previous result of the MDWZ (multiple descriptions in the Wyner-Ziv setting) problem in which none of the side information is known at the encoder. It is shown that when side information is absent at the encoder, there is a performance loss. The proposed scheme and its achievable region have practical significance. It offers theoretical insight into the multiple description video coding (MDVC) and suggests an optimal coding strategy.