Improving MIDI-audio alignment with acoustic features

This paper describes a technique to improve the accuracy of dynamic time warping-based MIDI-audio alignment. The technique implements a hidden Markov model that uses aperiodicity and power estimates from the signal as observations and the results of a dynamic time warping alignment as a prior. In addition to improving the overall alignment, this technique also identifies the transient and steady state sections of the note. This information is important for describing various aspects of a musical performance, including both pitch and rhythm.