Software for Multi Processor System on Chip: moving an MPEG4 decoder from generic RISC platforms to CELL

摘要

This paper presents the challenges encountered during the process of moving an MPEG4 decoder implementation from RISC based platforms to CELL processor. It presents multiple implementations of MPEG4 video decoder on a CELL processor, using different software partitioning and mapping schemes. The approach starts from a generic representation of an MPEG4 video decoder, from which multiple customized MPEG4 video decoders can be obtained (i.e. different number of tasks, video resolutions, frame-rates, etc). Each of these configurations of MPEG4 video decoders was mapped and executed on a CELL processor. During previous works, this was already realized using multi-RISC based Multi Processor System on Chip (MPSoC) platforms. However, by changing to CELL processors, new challenges and problems appeared. They must be considered and solved, in order to obtain a running MPEG4 video decoder on CELL. This paper presents these challenges and problems, along with some solutions. Finally, some performance results are presented for different MPEG4 video decoders implementations on a CELL processor. This paper is focusing on the portation only, and does not cover the final optimization phase using CELL processor specific code optimization techniques.