2-DIMENSIONAL MEMORY ALLOWING ACCESS BOTH AS ROWS OF DATA WORDS AND COLUMNS OF DATA WORDS

A structure and a format for providing a video signal encoder under the MPEG standard are provided. In one embodiment, the video signal interface is provided with a decimator for providing input filtering for the incoming signals. In one embodiment, the central processing unit (CPU) and multiple coprocessors implements DCT and IDCT and other signal processing functions, generating variable length codes, and provides motion estimation and memory management. The instruction set of the central processing unit provides numerous features in support for such features as alpha filtering, eliminating redundancies in video signals derived from motion pictures and scene analysis. In one embodiment, a matcher evaluates 16 absolute differences to evaluate a "patch" of eight motion vectors at a time.