Experiences with software MPEG-2 video decompression on an SMP PC

Software implementations of MPEG decompression provide flexibility but at the cost of being CPU intensive. We describe our results from implementing a two process MPEG-2 video decompression algorithm in software on a dual processor SMP machine. Our approach attempts to decompose the video decoding process into functional (rather than spatial) sub-tasks. This approach will allow us to more naturally extend the MPEG-2 video decompression to work with NOW technologies. We have tried out two different approaches, one using shared memory and the other using threads to parallelize the MPEG decoding process on a dual processor SMP system. Our results indicate that the common myth of “MPEG decoding is memory bottlenecked” is false. In particular our results show that a speedup of up to 1.7 is obtainable by using a simple functional decomposition of the MPEG decoder