Variable Block Size Techniques for Motion Sequence Coding

Major tools for the motion compensated coding, such as motion estimation, transform coding, and vector quantization, are block based techniques. So, block size is one of fundamental design parameters, but, until recently, a xed block size is usually selected considering the simplicity of implementation. However, if the block size is varied according to the locally changing characteristics, an additional gain will be achieved. Hence, a variable block size(VBS) techniques has been proposed to exploit the merits of adapting the block size. Hence, in this paper, an intensive investigation on the existing VBS techniques is performed rst with a special emphasis on the above three tools of MCC. Then, as an example of the VBS techniques for the motion sequence coding, a R-D optimized motion estimation approach employing a novel hierarchical VBS structure is proposed.