MPEG-4 SP/ASP decoder for a DSP-based Multi-Format IP Set-Top Box

Internet protocol set-top boxes (IP STBs) based on single-processor architectures have been recently introduced in the market. In this paper, the implementation of an MPEG-4 simple profile (SP) / advanced simple profile (ASP) video decoder for a multi-format IP STB based on a TMS320DM641 DSP is presented. An initial raw-C decoder for PC platform was fully tested and ported to the DSP. Using this code as a starting point, an optimization process that achieves a 90% speedup, allowing real-time MPEG-4 SP/ASP decoding using the aforementioned DSP, is described. The MPEG-4 decoder has been integrated in the IP STB and tested in a real environment using DVD movies and actual digital TV channels with excellent results