Automatic alignment of a musical score to performed music

Abstract

This paper presents several methods for the alignment of a music score (given in MIDI form) to a human performance of the same musical piece. Two distinct cases are considered: first, MIDI-to-MIDI alignment, where rhythm changes, note time shifts, and player errors are handled by a Dynamic-Programming (DP) algorithm. Next, a method for MIDI-to-audio alignment is presented, incorporating spectral data into the DP method. Experiments on a music database showed the effectiveness of the alignment algorithms. For cases where the alignment process gets trapped in a wrong local minimum, an efficient manual bootstrapping method was developed and shown to lead to the selection of the correct alignment.