Schemes for error resilient streaming of perceptually coded audio

This paper presents novel extensions to our earlier system for streaming perceptually coded audio over error prone channels such as mobile IP. To improve error robustness while maintaining bandwidth efficiency, the new extensions combine the strength of an error resilient coding scheme in the sender, a prioritized packet transport scheme in the network and a compressed domain error concealment strategy in the terminal. Different concealment methods are used for each part of the coded audio data according to their perceptual importance and statistical characteristics. In our current implementation, we employed MPEG-2 Advanced Audio Coding (AAC) encoded bitstreams and an RTP/UDP-based test system for performance evaluation. Simulation results have shown that our improved streaming system is more robust against packet losses in comparison with conventional methods.