[Theora-dev] VP3 Compatibility and SIMD Optimizations

Mike Melanson mike at multimedia.cx
Wed Mar 9 08:40:00 PST 2005

	A few questions: Is libtheora strictly backward compatible with VP3? 
Can I set it up to shove raw VP3 data through and trust it to decode the 
same way as On2's open source code did, loop filters and all?

	Also, is libtheora just supposed to be a C-based reference 
implementation? I was looking through the code and noticed a distinct 
lack of any kind of optimizations. Naive tree-based Huffman decoding; no 
SIMD (MMX/SSE2/AltiVec) optimizations. I read some murmurs about some 
MMX optimizations. I realize that there is a desire to make this lib 
cross-platform compatible. Are you looking for a solution along those 
lines? 2 solution sets: One for Intel ASM syntax, one for AT&T? NASM 
dependency? Looking for optimizations over and above On2's original source?

	-Mike Melanson

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