Performance Following: Real-Time Prediction of Musical Sequences Without a Score

This paper introduces a technique for predicting harmonic sequences in a musical performance for which no score is available, using real-time audio signals. Recent short-term information is aligned with longer term information, contextualizing the present within the past, allowing predictions about the future of the performance to be made. Using a mid-level representation in the form of beat-synchronous harmonic sequences, we reduce the size of the information needed to represent the performance. This allows the implementation of real-time performance following in live performance situations. We conduct an objective evaluation on a database of rock, pop, and folk music. Our results show that we are able to predict a large majority of repeated harmonic content with no prior knowledge in the form of a score.