Subject: Re: Can a timbre affected by a shifted virtual pitch evoked by From: Alain de =?iso-8859-1?Q?Cheveign=E9=27?= <Alain.de.Cheveigne(at)IRCAM.FR> Date: Tue, 25 Feb 2003 01:35:05 +0100>Just to understand the nomenclature here, by "autocorrelation" do we >mean autocorrelation of the pressure signal waveform? There are two types >that are used for pitch detection that I know of, multiplicative and >subtractive. Here is a nice review of these types: > >Alain de Cheveigne, "YIN, a fundamental frequency estimator for speech >and music", JASA 111(4), 1917-1930 (April 2002). > >de Cheveigne developed a refinement of the subtractive method which seems >to be very accuracte for speech and solo music. However, I don't think >it has been tested on inharmonic signals, like the ones Chen-Gia gives. I should warn that that paper describes an F0 estimation _method_ rather than a pitch perception _model_.Ý An earlier paper (JASA 103, 1261-1271) deals with pitch and is probably easier to read. Method and model have been tested on inharmonic signals.Ý They behave as expected from the quasi-periodic nature of the signals.Ý The various pitch shifts observed experimentally are well accounted for, as Meddis and Hewitt (1991) or Cariani and Delgutte (1996) have shown. As de Boer pointed out in his thesis (1956) and in a famous chapter (1976), autocorrelation and variants on one hand, and pattern matching (e.g. Terhard and others) on the other make essentially equivalent predictions.Ý The "first effect" results because the models follow the pseudoperiod (or pseudofundamental) of the stimulus.Ý The "second effect" results from (a) greater emphasis on components within a "dominant region" of the spectrum, and (b) combination tones. de Boer's (1976) chapter is hard to find but well worth searching for. Alain --- de Boer, E. (1956). On the "residue" in hearing. unpublished doctoral thesis, University of Amsterdam. de Boer, E. (1976). On the "residue" and auditory pitch perception. Handbook of sensory physiology. W. D. Keidel and W. D. Neff. Berlin, Springer-Verlag: 479-583. Cariani, P. A. and B. Delgutte (1996). ÅgNeural correlates of the pitch of complex tones. I. Pitch and pitch salience.Åh J. Neurophysiol. 76: 1698-1716. Cariani, P. A. and B. Delgutte (1996). ÅgNeural correlates of the pitch of complex tones. II. Pitch shift, pitch ambiguity, phase-invariance, pitch circularity, rate-pitch and the dominance region for pitch.Åh J. Neurophysiol. 76: 1717-1734. Meddis, R. and M. J. Hewitt (1991). ÅgVirtual pitch and phase sensitivity of a computer model of the auditory periphery. I: Pitch identification.Åh J. Acoust. Soc. Am. 89: 2866-2882. Meddis, R. and M. J. Hewitt (1991). ÅgVirtual pitch and phase sensitivity of a computer model of the auditory periphery. II: phase sensitivity.Åh J. Acoust. Soc. Am. 89: 2883-2894. --- -- Alain de Cheveigne' Ircam - CNRS, 1 place Igor Stravinsky, 75004, Paris, FRANCE. email: Alain.de.Cheveigne(at)ircam.fr, phone: +33 1 44 78 48 46