Moving Picture Experts Group (MPEG) decoding is a complex process: a decoder must read the MPEG data stream, decode its pieces, and then perform the proper transforms to generate an audio signal as output. The demand for low-cost, low-power, single-purpose MPEG decoder chips is high, and it is likely to remain so.

This paper notes that a pure hardware (application-specific integrated circuit (ASIC)) solution occupies one end of the design spectrum. However, it is relatively difficult to implement as part of the decoding process, and requires complex decision making logic. At the other end of the spectrum is a programmable digital signal processor (DSP) that provides flexibility and programmability, but at the expense of power (and probably chip size). The authors then argue that the ideal device is probably somewhere in the middle, with both a programmable component and a hardware component, each handling the part of the processing for whi!ch it is best suited.

A system designed around these principles is defined, and has been implemented. The authors’ system uses about twice the number of transistors as a pure ASIC design, but runs at a lower clock speed, and takes less power. It also uses about one-third of the transistors of a software solution, and therefore is substantially (physically) smaller. Since their design is a prototype, it is likely that additional power and space savings could result from production-level engineering.