Rate-distortion optimized motion compensation for video compression using fixed or variable size blocks

The authors describe a method for optimizing in a rate-distortion sense the performance of block matching motion compensation for video compression using fixed or variable size blocks. They apply recent advances in rate allocation theory and optimal tree structures to the choice of motion vector and block size for each region of the prediction image. They show that a variable block size algorithm using an optimized tree structure yields a significant improvement in rate-distortion performance over traditional motion compensation with a fixed block size. The computational complexity of such a system is not significantly higher than that of a fixed block size system