Index of /~echew/papers/SMC2004

Icon  Name                    Last modified      Size  Description
[DIR] Parent Directory                             -   
[   ] ec-smc04-paper.pdf      26-Aug-2004 05:32  811K  
[   ] ec-smc04-presentatio..> 25-Oct-2004 09:05  3.6M  
[TXT] references.txt          17-Aug-2004 16:35  367   

In this directory are the PDF file for the paper and presentation titled:

"REGARDS ON TWO REGARDS BY MESSIAEN:
Automatic Segmentation using the Spiral Array"

by Elaine Chew (echew@usc.edu)

The paper was presented at the 
Sound and Music Computing '04 Conference
Jim/Cim'04 - October 20-22 2004, Paris, France.

The paper appears in the Proceedings of the
Sound and Music Computing '04 Conference

The presentation took place 5:20PM at 
IRCAM in the Centre Georges Pompidou 

The conference website is at 
http://smc04.ircam.fr

The conference program is at
http://smc04.ircam.fr/PaperSessionSchedule.html

COMPLETE PAPER and POWERPOINT PRESENTATION 
Click on ec-smc04-paper.pdf if you wish to view the paper in PDF format.
Click on ec-smc04-presentation.pdf if you wish to view the presentation 
in PDF format

--'--,--'--,--'--,--'--,--'--,--'--,--'--,--'--,--'--,--'--,--'--,--'--

"REGARDS ON TWO REGARDS BY MESSIAEN:
Automatic Segmentation using the Spiral Array"

by Elaine Chew (echew@usc.edu)

ABSTRACT: Segmentation by pitch context is a fundamental process in
music cognition, and applies to both tonal and atonal music.  This
paper introduces a real-time, O(n), algorithm for segmenting music
automatically by pitch collection using the Spiral Array model.  The
segmentation algorithm is applied to Olivier Messiaen's Regard de la
Vierge (Regard IV) and Regard des prophetes, des bergers et des Mages
(Regare XVI) from his Vingt Regards sur l'Enfant Jesus.  The algorithm
uses backward and forward windows at each point in time to capture
local pitch context in the recent past and not-too-distant future.
The content of each window is mapped to a spatial point, called the
center of effect (c.e.), in the interior of the Spiral Array.  The
distance in the Spiral Array space between the c.e.'s of each pair of
forward and backward windows measures the difference in pitch context
between the future and past segments at each point in time.
Segmentation boundaries then correspond to peaks in these distance
values.  This paper explores and analyzes the algorithm's segmentation
of post-tonal music, namely, Messiaen's two Regards, using various
window sizes.  The computational results are compared to manual
segmentations of the pieces.  Taking into account the entire piece,
the best case computed boundaries are, on average, within 0.94% (for
Regard IV) and 0.08% (for Regard XVI) of their targets.