Re: Rhythm perception

[Henkjan Honing <honing@xxxxxx>]

On 15 Nov 2005, at 15:27, Dan Ellis wrote:

> > >  We were discussing rhythm patterns the other day and the  
> > > question came
> > >  up about how one determined the start of a pattern.
>
> I think this is the "downbeat detection" problem, which is distinct  
> from
> the problem of deciding the main repetitive period of the rhythm
> i.e. the spacing between downbeats.

"beat induction" (footapping, beat tracking, tempo tracking etc) has  
(at least) two components: phase and period.  Longuet-Higgins & Lee  
(1984) determine both of a given rhythm, Large & Kolen do a  similar  
thing using a couple oscillator model.

Ed with probably join is as well ...:-)

Henkjan



> I'm not a musicologist, but I've
> tried to build a system to align downbeats in different rhythm  
> patterns,
> so I've thought about it a little.
>
> Here's one piece of evidence: Tristan Jehan presented a poster at the
> recent Mohonk WASPAA on a machine learning approach for predicting
> the downbeats, which he tested on a style of Brazilian music called
> maracatu.  He played the maracatu examples to listeners familiar with
> northern-hemisphere western music, and they could not identify the
> downbeat - but of course maracatu fans have no problem indicating the
> appropriate downbeat.
>
>   http://web.media.mit.edu/~tristan/Papers/WASPAA05_Tristan.pdf
>
> That to me is powerful evidence that downbeat is a cultural norm  
> and not
> strongly based on some universal.
>
>   DAn.



************************************

Henkjan Honing
E honing@xxxxxx
I http://www.hum.uva.nl/mmm/hh/

Music Cognition Group
I http://www.hum.uva.nl/mmm/
F feed://www.hum.uva.nl/mmm/news.rss

************************************