[Ffmpeg-devel] [PATCH] another vorbis optimization

Loren Merritt lorenm
Wed Aug 9 08:50:17 CEST 2006

On Tue, 8 Aug 2006, Michael Niedermayer wrote:
> hmm currently we add the BIAS during the windowing, maybe it could
> be done prior to the imdct and only to a few coeffs, iam not sure though my
> knowledge of the mdct-windowing thingy isnt too good
> someone simply would have to feed a constant (=BIAS) vector through
> the windowing + MDCT to see if the resulting vector is (approximately) sparse
> or not

In a 128 sample block, the first 62% of the coefficients are nonzero.
In a 1024 sample block, 35%.

--Loren Merritt

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