Pitch Estimation by the Pair-Wise Evaluation of Spectral Peaks

In this paper, a new approach for pitch estimation in polyphonic musical audio is presented. The algorithm is based on the pair-wise analysis of spectral peaks. The idea of the technique lies in the identification of partials with successive (odd) harmonic numbers. Since successive partials of a harmonic sound have well defined frequency ratios, a possible fundamental can be derived from the instantaneous frequencies of the two spectral peaks. Consecutively, the identified harmonic pairs are rated according to harmonicity, timbral smoothness, the appearance of intermediate spectral peaks, and harmonic number. Finally, the resulting pitch strengths are added to a pitch spectrogram. The pitch estimation was developed for the identification of the predominant voice (e.g. melody) in polyphonic music recordings. It was evaluated as part of a melody extraction algorithm during the Music Information Retrieval Evaluation eXchange (MIREX 2006 and 2009), where the algorithm reached the best overall accuracy as well as very good performance measures.