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Sound descriptors references?

catart-mubu
#1

Hi there,
I’d like to know if you got some link references to the sound descriptors used with usual mubu segmentation.

I understand these or not as:

  • frequency mean : pitch
  • energy mean : like a mean of all bark energy bins?
  • periodicity mean : ?
  • AC1 mean : ?
  • loudness mean : perceived “volume”
  • centroid mean : spectrum barycenter
  • spread mean : how the segment spread around the centroid (kind of noisiness)
  • skewness mean : kind of measure of the assymetry of spectrum around centroid
  • kurtosis mean : ?

If you can give some “perception or musical or more listener understandable” interpretations of skewness, kurtosis, periodicity and AC1, I’d be happy :slight_smile:

links allowed, we can read it :slight_smile:

#2

I’ll put this in pipo.descr help, if it is clear enough:

The first 4 descriptors are from yin pitch tracking:

  • Frequency: the f0 or fundamental frequency
  • Energy: linear signal energy
  • Periodicity [0…1]: f0 quality factor, pitch-ness
  • AC1 [0…1]: first order autocorrelation coefficient, corresponds to spectral tilt, related to vocal or instrumental effort. Very effective e.g. for trumpet “brassyness”.

The next descriptors are derived from the signal spectrum:

  • Loudness [cB]: ITU-R 468 weighted FFT to respect the frequency-specific sensitivity of the human ear.
  • Centroid: brilliance (1st spectral moment)
  • Spread: width of spectrum (2nd spectral moment)
  • Skewness: imbalance around centroid (3rd spectral moment)
  • Kurtosis:skirt width (4th spectral moment)
1 Like
#3

Clear enough.
I don’t know how to use AC1 btw.

Sorry for having missed the pipo.descr help…

#4

as always, many of these will be show fine nuances only when the big ones (loudness, pitch, brilliance, periodicity) are constant
for AC1, try shouting or trumpet from mf to fff: loudness saturates, but ac1 increases

#5

Can I second that we put these in pipo.descr help — or indeed in other places too?

I think there should be some clear link from cataRT-mubu-overview for instance