I attended Altera's DSP showcase/seminar in Rochester, there was a large presence for interest in implementing MPEG4 (section 10 or 11, I can't remember) for HDTV applications. You didn't say if the advice you are searching for is for a commercial product, R&D science project or a student project but even implementing something real time for DVD quality (720x480) is worth considering.
I think a while back somebody announced the availability of JPEG library on the
A slightly different approach is using a tool like ImpulseC
Maybe it is the bubble I have been living in, but your clock speed seems high, what device families are you considering? I have seen 80 Mhz designs outperform similar applications on gigahertz PC. Don't let PC marketing skew your objectivity (or maybe it is there choice in operating systems).
Could you tell us more about the purpose of your project and you end application?
Derek