Softbit-source decoding based on the turbo-principle

This contribution deals with a robust decoding approach of source codec parameters called Softbit-Source Decoding. It can be considered as an error concealment technique which estimates codec parameters at the receiver utilizing residual redundancy remaining after source coding and channel decoder reliability information. In this paper we will apply the TURBO-principle to SoftbitSource Decoding. We derive a formula that shows how different terms of residual redundancy can be transformed into independent extrinsic information utilizable in iterative processes. After introducing a new, iterative approach to Softbit-Source Decoding, we will analyze the influences of different bit mappings and of the number of iterations. Finally, the new approach will be compared to conventional techniques with respect to performance and complexi ty.