[FFmpeg-devel] ffvorbis, inverted output

Benjamin Larsson banan
Sun Sep 28 21:00:00 CEST 2008

>> I posted a patch a long time ago that calculated the window on the fly.
>> With the code it would be easy to scale the window in any way you want
>> and it would be as fast as now.
> Cool. I can't find it now in the mailing list archives (link is always
> welcome), but do you know why it was not applied yet?

Well it would only save some space so I forgot about it. The problem was
how to reuse the tables.

> In any case, just having a scaled window is not enough (unless I'm
> misunderstanding you). On the boundary of different sized blocks we need
> to process a 'flat' part of a window which is performed by that 
> 'copy_normalize' function. If the scaling was done on window only, the
> function 'copy_normalize' would become slower and not turn into a simple
> memcpy operation.

I forgot about those. Maybe a scaling of the twiddle factors to the fft
will fix that ?

Benjamin Larsson

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