[vorbis] Video codec

[Monty]

I don't chime in on this often, but I think I will here...

> MPEG-2, at moderate (20:1 [10 Mbps, CBR, 4:2:0] ) to high compression ratios 
> (40:1 [5 Mbps, CBR, 4:2:0] ), creates several kinds of artifacts.  The most 
> noticeable ones are three:
> 
> 1) Blocking noise (blocks that are 8 or 16 pixels square)

Due to the nlg(n) nature of the DCT.  Wavelets are linear time transforms and 
so do not require subblocking.

> 2) "Mosquito" noise (irregular dots around sharp edges, like letters or 
> numbers)

Due to MDCT and it's non-local quantization artifacts.

> 2) Low-level DCT noise, crawling dots on flat surfaces

Same.

These are the biggest reasons I like wavelets ;-)  No subblocks, all *these* 
problems disappear.

Monty

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