Distributed video coding with zero motion skip and efficient DCT coefficient encoding
In this paper, we propose a suite of efficient schemes for the representation of spatial and temporal correlations of video signals in distributed video coding (DVC). These schemes consist of zero motion skipping, Gray codes, and sign bits coding of DCT coefficients developed to improve the overall rate-distortion (R-D) performance of distributed video coding. Existing schemes have focused on exploiting the spatial and temporal correlation without sufficient investigation on the efficient representation of the correlation. We believe this is one of the reasons that there still exists substantial gap between current DVC and traditional hybrid video coding. In traditional hybrid coding, a suite of efficient representation schemes such as zig-zag scan, run length code, and skipped macroblock have contributed significantly to excellent R-D performance. The efficient representation schemes we developed for DVC in this research will also lead to improved rate-distortion performance comparing with existing DVC schemes. We present in this paper the overall framework for the proposed zero motion skip and the analysis for efficient representations of both DCT coefficients and their signs. The experiment results show that the distributed video coding based on these efficient representations is able to achieve considerably improved rate-distortion performance over existing schemes.