Apparatus for estimating motion for compressing image data

PURPOSE: A motion estimator for video data compression is provided to carry out motion estimation according to the most suitable algorithm selected by a user. CONSTITUTION: A motion estimator(20) for video data compression includes a demultiplexer(210), a motion estimating unit(200), and a multiplexer(230). The demultiplexer receives current video data and a select flat from a user and outputs the current video data through one of a plurality of output ports according to the select flag. The motion estimating unit carries out motion estimation according to one of a plurality of motion estimation algorithms according to the output signal of the demultiplexer and outputs a motion vector. The multiplexer receives the select flag and outputs the motion vector from the motion estimating unit according to the select flag.