Research On Correlation-based Distributed Video Coding

Distributed video coding (DVC) is a new video compression paradigm with low complexity at the encoder which has been an efficient solution for some particular applications such as wireless multimedia networks and wireless surveillance. And transform-domain DVC has been the main research object in DVC because of the high compression efficiency.However, quantization is the key reason causing the loss of useful information, especially when the operation is coarse leading to the limit of the system performance. In this paper, a correlation-based transform-domain DVC scheme is proposed to solve the problem.In the scheme, the blocks of a WZ frame are divided into well-correlated blocks and badly-correlated blocks. The components of the well-correlated blocks and some of the low frequency components of the badly-correlated blocks are processed as in the conventional transform-domain DVC. And the remaining components of the badly-correlated blocks are replaced by the corresponding ones of the matching blocks in the previous key frame. With the scheme, the quantization loss can be reduced significantly. The simulation results demonstrate that the performance of the correlation-based transform-domain DVC can achieve 2~5dB gains comparing with the transform-domain distributed video coding when the quantization is coarse. Two schemes combining the correlation-based transform-domain DVC and the conventional transform-domain DVC are also proposed to make use of the high performance of the latter solution when the quantization is fine.