[FFmpeg-devel] [PATCH] avcodec/dcaenc: Use ffmpeg mdct instead of own implementation

[Даниил Чередник]

Hysterically dcaenc uses own implementation of time->frequency
transformation used by psychoacoustic. But actually function named fft in
original dcaenc code is not fft. Power spectrum looks similar to mdct, and
Alexander E. Patrakov told me it is MDCT. But for me it is still a bit
strange, because of output size, and absent phase shift sensitivity. I was
thinking about MCLT. But again, result of transformation original function
was different. So I decided to use ffmpeg mdct transformation here.


Results:

I could not hear the difference between original and modified version.

I got approximately 10% performance boost.

-- 
Daniil Cherednik
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