Multimode video coding for noisy channels
We focus on the design of robust video compression schemes for transmission over noisy channels. A multimode video coding framework is introduced, which enables optimizing the tradeoff between the conflicting objectives of high compression efficiency and error resilience. The starting point is a simple block-based predictive coder, with no motion compensation, for which we develop the robust multimode video compression scheme. The proposed iterative design algorithm for multimode video coders directly minimizes the overall rate-distortion cost. We show that several conventional joint source-channel coding mechanisms can be incorporated within a multimode scheme to further enhance the video coder performance. Simulation results of compressing benchmark video sequences for transmission over noisy channel conditions are presented. They demonstrate that multimode coders outperform conventional fixed length approaches and can achieve substantial gains of more than 6 dB in PSNR of the reconstructed picture.