Area Efficient SAD Architecture for Block Based Video Compression Standards

Block based motion estimation is one of the critical task in video compression standards such as MPEG-4, H.263, H.264. The key element of the block based motion estimation algorithms is the matching criteria. SAD(Sum of Absolute Difference) is the most common matching criteria chosen in video coding because of its low complexity, good performance and ease of hardware implementation. By utilizing the concept of reversibility a novel compression array unit using reversible 4:2 compressor has been proposed. Experimental results indicate that the proposed compression unit will impose effectiveness on the SAD architecture in calculating the motion vectors with reasonable area overhead and power penalty. Keywords—Motion estimation, Sum of absolute difference, 4:2 Compressor, SAD architecture, Reversible gates.