[FFmpeg-user] resolution of the waterfall diagram of typical mp3 file

Nicolas George george at nsup.org
Mon Aug 8 12:34:11 EEST 2016

Le primidi 21 thermidor, an CCXXIV, Florin Andrei a écrit :
> Using python/numpy or some other tools, I calculate the spectrum of the
> whole song, either all at once if possible, or using a reasonably large,
> shifting time window.
> I store that spectrum in a matrix.

And stop right here. If you compute the spectrum of the whole song, you do
not have a matrix, you have a vector. There is no time dimension in a
spectrum, it is the distribution of frequencies in the whole piece, period.

If you have a time dimension, that means you are doing something more
complex than a spectrum. You need to understand exactly what you are doing,
or more precisely what the others tools are doing for you. Then you can jump
back to my first mail.


  Nicolas George
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: Digital signature
URL: <http://ffmpeg.org/pipermail/ffmpeg-user/attachments/20160808/a498cbd4/attachment.sig>

More information about the ffmpeg-user mailing list