[FFmpeg-devel] [PATCH 0/4] fftw exploration (WIP)

[Paul B Mahol]

On 3/25/16, Ganesh Ajjanagadde <gajjanag at gmail.com> wrote:
> On Fri, Mar 25, 2016 at 9:36 AM, Nicolas George <george at nsup.org> wrote:
>> Le sextidi 6 germinal, an CCXXIV, Ganesh Ajjanagadde a ecrit :
>>> Depends on if it is small or not. Yes, in many codecs, FFT's are short
>>> length ones, e.g 512. However, on long lengths, e.g 8192+, as seen
>>> from the benches, there are sometimes 2x variations at the moment.
>>
>> And how much of the actual total decoding is spent in the FFT? Even a  *50
>> speedup would be useless if it is for a function that never amounts to
>> more
>> than 0,01% of the actual time. The FFT is probably not that negligible,
>> but
>> this is not a  *50 speedup either, and I have no idea how frequent are long
>> lengths.
>
> Paul had some interest in 2^17 fft's at a point.

And it was done in avfft. So feel free to improve our avfft instead.