Improved Score-performance Matching Using Both Structural and Temporal Information from MIDI Recordings

Automated score-performance matching is a complex problem due to the use of expressive timing by performers and the presence of notes that are unspecified in the score, such as performance errors and ornaments. Automated matchers typically use performance data extracted from MIDI recordings. For the most part, these algorithms use structural information, such as pitch and chronological succession, but do not use timing information. As a result, most matchers cannot deal satisfactorily with ornamented performances or performances that exhibit extreme variations in tempo. The matcher presented here relies both on structural and temporal information, allowing it to generate an accurate match even for heavily ornamented performances. Hand-made score-performance matches on a corpus of 80 MIDI recordings of organ performances of two pieces were used as ground truth data for a comparison with matcher results. The matcher achieved a nearly perfect accuracy rate. In addition, the matcher performed equally well or better than matchers previously described in the literature on a set of piano performances of two pieces by Chopin, thus demonstrating its versatility and robustness. We also propose a heuristic for the identification of ornaments and errors that is based on perceptual principles, and which could theoretically be amenable to empirical study. Finally, this matcher is designed to accommodate multi-channel MIDI recordings of performances from keyboard instruments with multiple manuals, such as organ or harpsichord. This feature makes it a potentially valuable tool for the investigation of ensemble performances of MIDI instruments.