AN IMAGE MOTION ESTIMATION SYSTEM WHICH DERIVES CANDIDATE BLOCK FROM INTERPOLATED MOTION VECTORS

A disclosed method and apparatus reduces the number of computations and simplifies the hardware required to provide compressed video output data. Video input data is converted into input pixel blocks. Best predicted blocks and associated motion vectors are determined for input pixel blocks located in a predetermined area of the image. In addition, candidate predicted blocks are determined for other input pixel blocks. This is done by .extrapolating motion vectors from the previously determined associated motion vectors and identifying candidate predicted blocks using the extrapolated motion vectors. The candidate predicted blocks are mutually compared, and one of the blocks is selected consistent with compression data rate requirements. The selected block is compressed to provide an output block which is formatted into an output data packet. A block match search is used to identify candidate Field predicted blocks and associated motion vectors from which other motion vectors are extrapolated and used to identify additional predicted blocks.