[FFmpeg-devel] [PATCH]HE-AACv1 try 3 (all missing functionality added)

Loren Merritt lorenm
Tue Feb 16 11:44:34 CET 2010

On Mon, 15 Feb 2010, Vitor Sessak wrote:
> Alex Converse wrote:
>> Why is ff_cos_tabs positive in quadrant II?
> Good question. I think I use only the first quadrant. Any one of the FFT 
> authors could clarify it?

FFT uses only the first quadrant. What comes after that in the table is 
not a continuation, but a reversed copy of the first quadrant to save on 
SIMD shuffle instructions.

--Loren Merritt

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