7. The method of claim 1 , wherein the generating comprises associating ones of the candidate harmonic segments having harmonic content levels satisfying the harmonic content predicate with respective classification records comprising an assignment to a harmonic segment class.
1. A method, comprising: estimating respective pitch values for an audio signal; identifying candidate harmonic segments of the audio signal from the estimated pitch values; determining respective levels of harmonic content in the candidate harmonic segments; and generating an associated classification record for each of the candidate harmonic segments based on a harmonic content predicate defining at least one condition on the harmonic content levels.