Emergent Formal Structures of Factor Oracle-Driven Musical Improvisations

  • Isaac Schankler
  • Jordan B. L. Smith
  • Alexandre R. J. François
  • Elaine Chew
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6726)


In this article, improvisations created with the factor oracle, a commonly used data structure in machine models of musical improvisation, are shown to exhibit certain formal structures independent of the musical content. We posit that these structures are in fact emergent properties of the behavior of the factor oracle itself. An expert improviser (the first author) performed a series of improvisations with Mimi, a factor oracle-driven multimodal system for human-machine improvisation, and the formal structures of each performance was independently analyzed by the performer and an experienced music structure annotator (the second author). Quantitative assessment of the similarity between the performer’s and the listener’s analyses was carried out using techniques from the field of automatic structure analysis. Supported by a comparison to baseline analysis approaches, the results suggest a high level of agreement between the two sets of analyses. Drawing upon this foundation of evidence, we discuss these analyses and their relationship to common classical forms, including canon- and rondo-like forms, as well as forms based on the juxtaposition of rhythmic cells.


Improvisation Factor oracle Musical structure Emergent structure 


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  1. 1.
    Allauzen, C., Crochemore, M., Raffinot, M.: Factor oracle: A new structure for pattern matching. In: Bartosek, M., Tel, G., Pavelka, J. (eds.) SOFSEM 1999. LNCS, vol. 1725, pp. 295–310. Springer, Heidelberg (1999)CrossRefGoogle Scholar
  2. 2.
    Assayag, G., Bloch, G., Chemillier, M., Cont, A., Dubnov, S.: OMax brothers: A dynamic topology of agents for improvization learning. In: Proceedings of the ACM Workshop on Music and Audio Computing, pp. 125–132 (2006)Google Scholar
  3. 3.
    Assayag, G., Dubnov, S.: Using factor oracles for machine improvisation. Soft Computing 8(9), 604–610Google Scholar
  4. 4.
    François, A.R., Chew, E., Thurmond, D.: Visual feedback in performer-machine interaction for musical improvisation. In: Proceedings of the International Conference on New Interfaces for Musical Expression, pp. 277–280 (2007)Google Scholar
  5. 5.
    François, A.R.: Time and perception in music and computation. In: Assayag, G., Gerzso, A. (eds.) New Computational Paradigms for Computer Music, pp. 125–146. IRCAM, Delatour (2009)Google Scholar
  6. 6.
    Lévy, B.: Visualising OMax. Technical report, Ircam (2009)Google Scholar
  7. 7.
    Smith, J.B.: A comparison and evaluation of approaches to the automatic formal analysis of musical audio. Master’s thesis, McGill University (2010)Google Scholar
  8. 8.
    Lerdahl, F., Jackendoff, R.: A Generative Theory of Tonal Music. MIT Press, Cambridge (1983)Google Scholar
  9. 9.
    Yorgason, B., Halliday, J., Colvard, C.: Variations Timeliner [computer software] (2008),
  10. 10.
    Lukashevich, H.: Towards quantitative measures of evaluating song segmentationu. In: Proceedings of the International Conference on Music Information Retrieval, pp. 375–380 (2008)Google Scholar
  11. 11.
    Boivin, J.: Musical analysis according to Messiaen: A critical view of a most original approach. In: Dingle, C., Simeone, N. (eds.) Olivier Messiaen: Music, Art and Literature, pp. 137–157. Ashgate Publishing, Ltd, Burlington (2007)Google Scholar
  12. 12.
    Boulez, P.: Stravinsky remains. In: Stocktakings from an Apprenticeship. Trans. Stephen Walsh, pp. 55–110. Clarendon Press, Oxford (1991)Google Scholar
  13. 13.
    Assayag, G., Bloch, G.: Navigating the oracle: A heuristic approach. In: Proceedings of the International Conference on Music Computing, pp. 405–412 (2007)Google Scholar
  14. 14.
    Cont, A., Dubnov, S., Assayag, G.: A framework for anticipatory machine improvisation and style imitation. In: Proceedings of Anticipatory Behavior in Adaptive Learning Systems, ABiALS (2006)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Isaac Schankler
    • 1
  • Jordan B. L. Smith
    • 1
  • Alexandre R. J. François
    • 2
  • Elaine Chew
    • 1
  1. 1.University of Southern CaliforniaLos AngelesUSA
  2. 2.Harvey Mudd CollegeClaremontUSA

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