A new method for optimal rate allocation for progressive image transmission over noisy channels

We present a new method for optimal rate allocation between a progressive image coder and a channel coder for noisy channels. A mathematical model for the embedded bit streams is developed and used as a new metric for such a joint source-channel coding optimization problem. It is further shown that maximization of such a new metric is equivalent to the maximization of a conventional PSNR measure. PSNR improvements up to 0.3 dB over very noisy channels at low bit rate are achieved by using the proposed method without any additional overheads. Furthermore, the PSNR performance obtained by using the proposed method is upper bounded by those of the conventional Monte Carlo method. Computational results and numerical comparisons consistently verify the merit of the proposed technique