Method and system for adaptive motion estimation

A system for adaptive motion estimation, which sets a search range in a previous frame in order to find a corresponding block in the adaptive search range according to each block of a current frame and to accordingly determine a corresponding motion vector, the system comprising:

• a motion estimation unit, which determines a motion vector by referring to a target block of a current frame and reference blocks in a search range of a previous frame;
• a mode decision unit, which determines a compression mode according to the target block, the reference blocks and the motion vector and outputs a mode data corresponding to the compression mode;
• a mode memory unit, which stores the mode data output by the mode decision unit;
• a motion vector memory unit, which stores the motion vector determined by the motion estimation unit;
• and
• a search range specifying unit, which determines a search range according to the mode data stored in the mode memory unit and the motion vector stored in the motion vector memory unit.