AN ADAPTIVE SEARCH LENGTH ALGORITHM FOR BLOCK MATCHING MOTION ESTIMATION

This paper presents a new fast search algorithm for block matching mot ion estimation called the adaptive search length (ASL) algorithm. The ASL algorithm adaptively varies the number of positions searched for e ach block while still maintaining control of the average number of sea rches per block for each frame. Experimental results show that the pea k signal-to-noise ratio (PSNR) of decoded sequences which were coded u sing the ASL algorithm is within 0.25 dB of the PSNR of decoded sequen ces which were coded using the full search block matching algorithm. I t is also shown that the ASL algorithm requires only 10% of the comput ations required by the full search algorithm to achieve this level of decoded image quality.