An evaluation of score-informed methods for estimating fundamental frequency and power from polyphonic audio

Abstract

Robust extraction of performance data from polyphonic musical performances requires precise frame-level estimation of fundamental frequency (f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> ) and power. This paper evaluates a new score-guided approach to f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> and power estimation in polyphonic audio and compares the use of four different input features: the central bin frequencies of the spectrogram, the instantaneous frequency, and two variants of a high resolution spectral analysis. These four features were evaluated on four-part multi-track ensemble recordings, consisting of either four vocalists or bassoon, clarinet, saxophone, and violin (the Bach10 data set) created from polyphonic mixes of the monophonic tracks both with and without artificial reverberation. Score information was used to identify time-frequency regions of interest in the polyphonic mixes for each note in a corresponding aligned score, from which f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> and power estimates were made. The approach was able to recover ground truth f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> within 20 cents on average in reverberation and power within 5 dB for anechoic mixtures, but only within 10 dB for reverberant.