An adjustable multipath flatted-hexagon search algorithm for block motion estimation

A novel and simple speed/accuracy adjustable block-matching algorithm (BMA) based on multipath flatted-hexagon search (MFHS) is developed for motion estimation. In the proposed method, an adaptive threshold of BDM is introduced to determine the required search directions in order to escape from being trapped into a local minimum BDM for the purpose of adjusting the search speed and matching probability. The estimated motion vector will be refined at each search step until the searching process is stopped. Experimental results show that the proposed MFHS algorithm can achieve an average matching probability up to 98% near to that of FS and about 10 times of checking points faster than FS in most of real-world sequences, especially for horizontal-motion-biased image sequences.