ABSTRACT
Multimedia processing is expected to be the driving force for the evolution of both microprocessors and DSPs. Introduction of digital audio and video is the starting point of multimedia, because audio and video as well as texts, figures and tables are all in the digital form in a computer, and therefore, they can be handled in the same manner. However, digital audio and video require tremendous amount of information bandwidth, unless compression technology is employed. Audio and video information amount is deeply dependent on their required quality and varies in a wide range. For example, HDTV (1920×1080pixels with 60 fields/sec) is expected to be compressed into around 20 Mbit/sec while the H.263 [1] videophone terminal having sub-QCIF (128×96pixels) with 7.5 frames/sec is expected to require around 10 to 20 kbit/sec. Information rate difference reaches around 1000 times in this case. Compression techniques also require tremendous amount of processing, which is dependent on quality and information rate. The required processing rate has a range from one hundred MOPS (Mega Operations Per Second) to more than TOPS (Tera Operations Per Second). NTSC resolution MPEG-2 (MPEG-2 MP@ML) [2] decoding, for example, requires more than 400 MOPS and 30 GOPS are required for the encoding. This wide variety of processing amount and multimedia quality lead us to employ a variety of programmable implementations.
