Abstract: Based on the ME-Skip algorithm for motion estimation proposed by H.S.Kang, an advanced algorithm for motion estimation is presented. An improvement is made on the setting of matching error(measured by SAD) thresholds. There are two SAD thresholds in the new algorithm. The smaller one is used to overcome the propagation of the matching error, while
the larger one is applied to avoid the exectution of ME to the greatest degree. When the matching error based on the prediction of the motion vector is between two SAD thresholds, a search restricted in a small window is used to replace the original motion estimation. Results show that with a little increase in coding efficiency, the proposed algorithm reduces computational complxity in motion estimation by as much as 10%～20%.

Key words: MPEG-4, video compression, motion estimation and compensation