This operations is a specialisation of the general signal processing operator sig.envelope focused on auditory models.

Same as in sig.envelope.

• aud.envelope(…,'Mu',mu) computes the logarithm of the envelope, before the eventual differentiation, using a mu-law compression.. Default value for mu when 'Mu' is called: 100

• aud.envelope(…,'Lambda',l) sums the half-wave rectified envelope with the non-differentiated envelope, using the respective weight 0<l<1 and (1-l). Default value for lambda: .8

• `aud.envelope(…,'Klapuri06') extracts the envelope following a modelling of human perception suggested in (Klapuri et al., 2006). This corresponds to

e = aud.envelope(…,'Spectro','UpSample','Mu','HalfwaveDiff','Lambda',.8);
sug.sum(e,'Adjacent',10)

Same as in sig.envelope.