Unequal error protection of embedded video bitstream with optimized FEC

Abstract

In this paper, an optimized unequal error protection scheme using Forward Error Correction (FEC) for transmission of embedded video bitstream over AWGN channel is investigated. The scheme exploits the non-uniform importance and error sensitivity of the bits generated by the a wavelet video coder. Depending upon their importance in the reconstruction of the video, the bitstream is first divided into High Priority (HP) and Low Priority (LP) substreams. Then appropriate FEC is applied to these substreams to protect them against the channel errors. The optimal FEC parameters are searched using an offline optimization technique subject to constraint that end-to-end transmission distortion is minimized. A look-up table with optimal FEC parameters for wide range of channel conditions, is designed. Furthermore, this paper also argues that whether optimized UEP has any advantage over EEP for protection of embedded bitstream. This scheme is suitable for real-time video communication using portable devices which possess low processing capabilities and small battery power.