Design of inverse DCT unit and motion compensator for MPEG2 HDTV decoding

Abstract

An MPEG2 video decoder core is implemented, which consists of an inverse discrete cosine transform (IDCT) unit and a motion compensator. By means of butterfly computation, multi-bit extension of distributed arithmetic, and improvement of critical paths, the IDCT unit achieves a high throughput, and the motion compensator calculates half-pel image dynamically so as to cover several types of picture prediction modes employed by MPEG2. The decoder core occupies 27 mm/sup 2/ in a 0.6-/spl mu/m triple-metal CMOS technology, processes a macroblock (16/spl times/16 pels) within 2.5 /spl mu/s, and therefore is capable of decoding HDTV (1920/spl times/1152 pels) resolution images in real time.