A Simple Score Following System for Music Ensembles Using Chroma and Dynamic Time Warping

It is disruptive for instrumentalists to turn the page of music sheet when they are playing instruments. The purpose of this study is to investigate how real-time music score alignment can serve as a tool for a computer-assisted page turner. We proposed a simple system which can be set up easily and quickly for use to solve the problem. The framework of the system has two parts: off-line preprocessing stage and online alignment stage. In the first stage, the system extracts chroma feature vectors from the reference recording. In the second stage, the system receives audio signals of live performance and extracts chroma feature vectors from them. Finally, the system uses Dynamic Time Warping (DTW) to find an alignment between those two sets of chroma feature vectors to mark the current measure of the score. The prototype system was evaluated by musicians in different music ensembles like string quartet and orchestra. Most musicians agreed that the system is helpful and can indicate the current measure of a live performance correctly. Some musicians, however, disagreed that the system turned the page at right time. The user survey showed that the best timing for page turning is user-dependent because it is highly to do with musicians' sight reading skills and speed.