Motion estimation is an important issue in H.264 video coding systems because it occupies a large amount of encoding time. In this paper

a novel search algorithm which utilizes an adaptive hexagon and small diamond search (AHSDS) is proposed to enhance search speed. The search pattern is chosen according to the motion strength of the current block. When the block is in active motion

the hexagon search provides an efficient search means; when the block is inactive

the small diamond search is adopted. Simulation results showed that our approach can speed up the search process with little effect on distortion performance compared with other adaptive approaches.