An outer bound for side-information scalable source coding with partially cooperating decoders

A side-information scalable model in which each receiver observes its own side-information, while the side-information pair is stochastically degraded with respect to the source, is considered. It is further assumed that a one way conference link with given capacity exists between the decoder observing the higher quality side-information and the one observing the degraded side-information. Our contribution is in deriving an outer bound on the rate-distortion region for this model. Specifically, we propose a modification to the technique presented by Tian-Diggavi which accounts for the presence of the conference channel.