[vorbis-dev] SIMD instructions

Pádár Attila mpxplay at freemail.hu
Wed Feb 5 16:04:43 PST 2003

These were my observations only... 
maybe they are not match with yours... 
I'll check again my optimizations, but I think so (I hope)
I haven't missed anything (or the bug is in my ear).
And everybody likes to follow his own way and
fortunately Vorbis is opensource (thank You for it).

If I modify float(s) to double(s) in 
vorbis_lsp_to_curve() : p and q local variables
and mdct.c/mdct.h : REG_TYPE
I get more high sounds at playing beta3/beta4 files.
But it's true that Vorbis 1.0 (RCx) routines are not so
precision sensitive (only the mdct part).

I attach my decoder-side-only Ogg Vorbis library (removed
all encoder-side functions to reduce code size (190k->55k))
There are some asm routines and a lot of x86 specific code,
but maybe some routines/optimizations are usefull in
your official/original code too (ie: codebook.c, floor1.c).
Check it, and if you think, use it, if you don't think, 
don't use it. :)

But keep up the good work!

best regards

btw. When will we get new Vorbis encoder?
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