Selection of variable block sizes in H.264

The paper aims at selecting an efficient variable block size mode in H.264 video coding standard for better compression performance. This standard allows video frames to be partitioned into variable block sizes such that blocks containing highly detailed motion are represented using small block sizes and the rest using large block sizes. New techniques for intelligent selection of the variable block sizes have been developed to reduce the computational complexity without sacrificing the quality of the coder. The proposed schemes are based on the motion vector cost and previous frame information. An improvement in the encoding time with negligible impact on the subjective and the quantitative performance has been achieved. A comparison of the proposed techniques for various test sequences is also provided.