Real-Time Pitch Spelling

  • Elaine ChewEmail author
Part of the International Series in Operations Research & Management Science book series (ISOR, volume 204)


This chapter describes and presents a real-time bootstrapping algorithm for pitch spelling based on the Spiral Array model [3]. Pitch spelling is the process of assigning appropriate pitch names that are consistent with the key context to numeric representations of pitch, such as MIDI or pitch class numbers. The Spiral Array model is a spatial model for representing pitch relations in the tonal system. It has been shown to be an effective tool for tracking evolving key contexts (see [4, 5]). Our pitch-spelling method derives primarily from a two-part process consisting of the determining of context-defining windows and pitch-name assignment using the Spiral Array. The method assigns the appropriate pitch names without having to first ascertain the key. The Spiral Array model clusters closely related pitches and summarizes note content by spatial points in the interior of the structure. These interior points, called centers of effect (CEs), approximate and track the key context for the purpose of pitch spelling. The appropriate letter name is assigned to each pitch through a nearest-neighbor search in the Spiral Array space. The algorithms utilize windows of varying sizes for determining local and long-term tonal contexts using the Spiral Array model.


Spelling Error Pitch Class Tonal Context Midi File Slide Window Algorithm 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We thank the referees and editors who have provided many detailed comments and helpful suggestions for improving this manuscript. The research has been funded by, and made use of shared facilities at, USCs Integrated Media Systems Center, an NSF ERC, Cooperative Agreement No. EEC-9529152. Any opinions, findings and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect those of NSF.


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.Centre for Digital MusicQueen Mary University of LondonLondonUK

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