[theora-dev] Updated VP3 Document

Timothy B. Terriberry tterribe at vt.edu
Mon Mar 1 09:35:18 PST 2004

> 	Timothy T.: I haven't lost all of your useful updates. But I am
> unfortunately too tired to include them on this update. They will make it
> in eventually.

Especially the one about Theora no longer having the opposite 
orientation that VP3 has (at least in the CVS version).

The other comment I'd make is that the DCT tokens are coded in terms of 
Huffman codes. The fact that the VP3 code re-derives the Huffman codes 
corresponding to a set of histograms every time you run it is mostly 
irrelevant. The histograms are fixed (in VP3), and so the codes are 
fixed. In Theora, the codes are specified in the bitstream directly, not 
in terms of a histogram.

Also, I don't remember if anyone ever asked before, do we have 
permission to incorporate pieces of this document (with attribution) 
into our own Theora bitstream spec.?
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