Rhythmic Similarity Carmine Casciato MUMT 611 Thursday, March 13, 2005

Overview  Music Tech research into rhythmic similarity  Representations  Problem of segmentation

Usage

 Computer accompaniment systems  Ethno-musicological research  Database management  Queries by humming  Genre classification  Speech processing

Paulus and Klapuri (2002)  Detects rhythmic similarity between musical samples containing arbitrary drum/percussive sounds  Removes sinusoidal components from sound to detect noisy percussive sounds, from this produces beat and measure estimations  Extracts loudness and brightness (mean square energy and spectral centroid, respectively) per measure  Dynamic Time Warping (DTW) finds optimal path between feature vectors  No training of system required

Foote, Cooper, and Nam (2002)  Derivation of ‘beat spectrum’  Feature used is power of FFT bins embedded into similarity matrix  Euclidean distance is used as similarity metric, tested against cosine angles between feature vectors, and FFT co- efficients

Ellis and Arroyo (2004)  Principal Component Analysis, a dimension reduction tool  Requires robust segmentation  Poor classification results

EigenRhythms (Ellis and Arroyo 2004)  Useful for generating variations?

Toussaint (2002)  Geometric representations of rhythms  Require extensive segmentation  Tests various distance metrics  Minimum Spanning Trees offer a framework for rhythmic development analysis

Toussaint Representations (2002)

Music Technology References  Ellis, D., and J. Arroyo Eigenrhythms: Drum pattern basis sets for classification and generation. In Proceedings of the International Conference on Music Information Retrieval.  Foote, J., M. Cooper, and U. Nam Audio retrieval by rhythmic similarity. In Proceedings of the International Conference on Music Information Retrieval.  Paulus, J., and A. Klapuri Measuring the similarity of rhythmic patterns. In Proceedings of the International Conference on Music Information Retrieval.  Toussaint, G A mathematical analysis of African, Brazilian, and Cuban clave rhythms. In Proceedings of BRIDGES: Mathematical Connections in Art, Music, and Science.

Other Disciplines  Gabrielsson, A Similarity ratings and dimension analyses of auditory rhythm patterns. Scandinavian Journal of Psychology 14: 138  60.  Lerdahl F., and R. Jackendoff A generative theory of tonal music. Cambridge: The MIT Press.  Powel, D., and P. Essens Perception of temporal patterns. Music Perception 2(4): 411  40.