A probabilistic method for tracking a vocalist
Lorin Grubb · The Journal of the Acoustical Society of America · 1999
When a musician gives a recital or concert, the music performed generally includes accompaniment. To render a good performance, the soloist and the accompanist must know the musical score and must follow the other musician’s performance. Both performing and rehearsing are limited by constraints on the time and money available for bringing musicians together. Computer systems that automatically provide musical accompaniment offer an inexpensive, readily available alternative. Computer accompaniment requires software that can listen to live performers and follow along in a musical score. An implemented system automatically accompanies a singer given a musical score. The focus is a method for robustly detecting the score position and tempo (performance rate) of the singer in real time. Robust score following requires combining information obtained both from analyzing a complex signal (the signer’s performance) and from processing symbolic notation (the score). The singer’s score position is characterized statistically using a model that combines the available musical information to produce a probabilistic position estimate. By making careful assumptions and estimating statistics from a set of actual vocal performances, a reasonable approximation of this model can be implemented in software and executed in real time during a performance.