A Partial Searching Algorithm and Its Application for Polyphonic Music Transcription

This paper proposes an algorithm for studying spectral contents of pitched sounds in real-world recordings. We assume that the 2-order difference, w.r.t. partial index, of a pitched sound is bounded by some small positive value, rather than equal to 0 in a perfect harmonic case. Given a spectrum and a fundamental frequency f0, the algorithm searches the spectrum for partials that can be associated with f0 by dynamic programming. In section 3 a background-foreground model is plugged into the algorithm to make it work with reverberant background, such as in a piano recording. In section 4 we illustrate an application of the algorithm in which a multipitch scoring machine, which involves special processing for close or shared partials, is coupled with a tree searching method for polyphonic transcription task. Results are evaluated on the traditional note level, as well as on a partial-based sub-note level.