On scalable coding in the presence of decoder side information
The problem of scalable coding while exploiting the decoder side information is considered. Prior work considered the two important cases concerning the degraded side information where source X and the side information variables (Y1, Y2) form a Markov chain in the order of either X - Y1 - Y2 or X - Y2 - Y1. While the encoding schemes for these settings differ considerably, they are both based on the combination of conditional codebook encoding, a standard tool in scalable coding, and random binning, conventionally used in decoder side information problems. In this paper, an encoding scheme is proposed solely on the basis of random binning, which essentially performs scalable and Wyner-Ziv coding simultaneously. Proposed scheme achieves the rate-distortion regions of prior results. A practical advantage of the unifying scheme is the fact that random binning can be realized via practical tools such as nested lattice codes and channel codes. Finally, motivated by the proposed encoding scheme, a network interpretation of scalable coding is considered. An achievable region is derived for this problem setting and the potential benefits of networked scalable coding are shown.