Transmission of hybrid-coded video including motion compensation and spatial prediction over error prone channel results in the well-known problem of error propagation because of the drift in reference frames between encoder and decoder. The prediction loop propa-gates errors and causes substantial degradation in video quality. Especially in H.26L video, both intra and inter prediction strategies are used to improve compression efficiency, however, they make error propagation more serious. This work proposes distortion models for H.26L video to optimally estimate the overall distortion of decoder frame reconstruction due to quantization, error propagation, and error concealment. Based on these statistical distortion models, our error robust coding scheme only integrates the distinct distortion between intra and inter macroblocks into a rate-distortlon based framework to select suitable coding mode for each macroblock, and so,the cost in computation complexity is modest. Simulations under typical 3GPP/3GPP2 channel and Internet channel conditions have shown that our proposed scheme achieves much better performance than those currently used in H.26L. The error propagation estimation and effect at high fractural pixel-level prediction have also been tested. All the results have demonstrated that our proposed scheme achieves a good balance between compression efficiency and error robustness for H.26L video, at the cost of modest additional complexity.
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