Subject: Re: Robust method of fundamental frequency estimation. From: "Beerends, J.G. (John)" <john.beerends@xxxxxxxx> Date: Thu, 1 Feb 2007 08:56:33 +0100 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>The only comment I have is that pitch is indeed a stochastic property (described neatly by Goldstein) and thus a pitch algorihtm should not predict "THE PITCH" but the "PDF of the PITCH". In 1988 I wrote a stochastic subharmonic pitch extraction algorithm that uses the idea of generating gaussian subharmonic function from which the PITCH PDF can be predicted, the idea was patented by Philips, a description of the idea can be found in chapter 5 of my PhD. (see http://www.darenet.nl/nl/page/repository.item/show?saharaIdentifier=tue: 304393 ) John Beerends TNO Information and Communication Technology The Netherlands -----Original Message----- From: AUDITORY - Research in Auditory Perception [mailto:AUDITORY@xxxxxxxx On Behalf Of Fred Herzfeld Sent: Thursday, February 01, 2007 01:38 To: AUDITORY@xxxxxxxx Subject: Re: Robust method of fundamental frequency estimation. Hello Roisin, I am sure that you do not really want to calculate the "fundamental" frequency of your note. The fundamental frequency is a well defined mathematical concept while on the other hand "pitch" is what we hear and is defined by the receiver (the ear in your case). It is also unfortunate that many well known researchers use the word "inharmonic" erroneously. As part of a larger work on "hearing" I have written a small section entitled "The Fundamental Frequency of a Vibration" which I am sending as an attachment. I think you and others on this list will find it most interesting. One problem that I do not mention in the above section is that the pitch of a note actually changes with amplitude. It is something that you should consider. A section on "pitch" is not yet complete. If anyone on the list would like to comment on tne attachment I am ready to defend it. Fred------------------------------------------------------- Roisin Loughran wrote: > Dear list, > > I was wondering if any of you know the most robust way to calculate > the fundamental frequency of a note across the range of a variety of > instruments? > > I'm currently working on a matlab program and have tried using the > auto-correlation method and the cepstrum method but have found that > these both have difficulty in calculating f0 of timbre-rich tones such > as those from a piano - particularly in the lower pitch ranges. Does > anyone know of a method that is more reliable in these regions or is > it necessary that I investigate such complex tones by a different means? > From examining a number of the FFTs from these signals it is tempting > to just pick the first strongest partial - the complex overtones just > seem to confuse the more complicated algorithms, but I realise that > this is hardly a reliable approach. > > Any suggestion would be greatly appreciated, Thanks in advance, > > Roisin Loughran > > ---------------------------------------------------------------------- > -- New Yahoo! Mail is the ultimate force in competitive emailing. Find > out more at the Yahoo! Mail Championships > <http://uk.rd.yahoo.com/mail/uk/taglines/default/championships/games/*ht tp://uk.rd.yahoo.com/evt=44106/*http://mail.yahoo.net/uk/>. > Plus: play games and win prizes. -- Fred Herzfeld, MIT '54 78 Glynn Marsh Drive #59 Brunswick, Ga.31525 USA This e-mail and its contents are subject to the DISCLAIMER at http://www.tno.nl/disclaimer/email.html