An apparatus performs motion estimation based on a reference image and a target image. The apparatus has a command memory for storing a motion estimation command list segment and a search engine connected to the command memory. The search engine retrieves and processes the command list segment stored in the memory. The search engine in turn has a reference window memory containing one or more reference data segments, a target memory containing one or more target data segments, and a data path engine for generating a score for each offset between data in the reference window memory and data stored in the target memory. A result memory receives outputs from the motion estimation search engine in the form of motion estimation result list segments. The reference window memory, target memory, and result memory may be double-buffered to minimize system memory latencies. Moreover, target and reference fetches may be shared by up to four search targets in a split search command. Additionally, the command list segment and the result list segment use an identical format. The size of each command in the command list and each result in the result list is also identical. The identical format and size characteristics allow results generated by a current search to be reused as a part of the command for the next search.