H {seewave} | R Documentation |
This function estimates the total entropy of a time wave.
H(wave, f, wl = 512, smooth = NULL)
wave |
data describing a time wave
or a Sample object generated loading a wav file
with loadSample (package sound). |
f |
sampling frequency of wave (in Hz).
Does not need to be specified if wave is a Sample object. |
wl |
window length for spectral entropy analysis
(even number of points). See sh . |
smooth |
envelope smoothing by floating average. See th . |
This function computes the product between the values obtained with
sh
and th
functions.
This then gives a global (time and frequency) estimation of signal entropy.
The frequency mean spectrum and the amplitude envelope needed for computing
respectively sh
and th
are automatically generated.
They can be controlled through wl
and smooth
arguments respectively.
See examples below and examples in sh
and th
for implications on the results.
A single value varying between 0 and 1 is returned. The value has no unit.
The entropy of a noisy signal will tend towards 1 whereas the entropy of a pure tone signal will tend towards 0.
Jérôme Sueur sueur@mnhn.fr
Sueur, J., Pavoine, S., Hamerlynck, O. & Duvail, S., in preparation.
data(orni) H(orni,f=22050) # [1] 0.766589 # changing the spectral parameter (wl) H(orni,f=22050,wl=1024) # [1] 0.7785917 # changing the temporal parameter (smooth) H(orni,f=22050,smooth=20) # [1] 0.7491108