[vorbis-dev] SIMD instructions

Pádár Attila mpxplay at freemail.hu
Thu Jan 30 16:36:37 PST 2003



Hello, just some comments:

1.
SSE2 uses 64-bit floats, Vorbis uses 32-bit...
If we use 64-bit precision instead of 32, the result will be different.
I've made an encoder/decoder with 64-bit precision
(I've changed float(s) to double(s) almost everywhere),
but the sound-result has changed, the tone was a little
different (not correct).

2.
The new (v1.0) huffman/codebook decoding is not
really good if we want to make a fast assembly code (normal x86).
It's easier to omptimize the older (RC3) routines...
(ie: we can do nothing with the bitreverse() function in asm)

Attila

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