What is "video" output? Data in a frame buffer? NTSC? Analog RGB at VGA syncrates? Uncompressed parallel RGB data for driving a TFT-LCD? What MPEG variant? MPEG-1? MPEG-2? MPEG-4? Do you need to support content scrambling? Do you need to support multiple interleaved program streams? What resolutions do you need to support? Is de-interlacing required?
For any conceivable application that needs MPEG decoding, a microcontroller is also required. So it's practical to integrate it into the one device for consumer parts.
The matrix of the answers to these and other issues makes a "generic" MPEG video IC impractical. There are hardware solutions to accelerate parts of the problem - iDCT, MC, etc, but they're integrated into high-performance video ASICs.
-- Lewin A.R.W. Edwards
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