Fast Joint Source-channel Coding Algorithms for Internet /wireless Multimedia

We consider joint source-channel coding for Internet and wireless multimedia applications. Embedded source bitstreams are protected against noise in both binary symmetrie channels (BSC) and packet erasure channels. For each channel, a local search joint source-channel coding (JSCC) algorithm is proposed to search for the optimal unequal error protection (UEP) scheme. Each algorithm starts with a linear-complexity step that maximizes the number of correctly decoded source bits, followed by a quick local refinement of the resulting UEP solution to minimize the average distortion. Experiments for both binary symmetrie channels and packet erasure channels with the SPIHT, JPEG2000 and 3D SPIHT coders show that our local search algorithms are nearoptimal in performance, whereas they are orders of magnitude faster than the best previous solutions.