[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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