RHYTHM FEATURE EXTRACTOR

The invention relates to a method of extracting a representation of its rhythmic structure, from a given signal. The representation is designed to yield a similarity relation between item titles. There is thus provided a method of extracting the numeric representation of a rhythmic structure for a given item of audio signal, from a database including percussive sounds in an audio signal, comprising the steps of: a) defining said rhythmic structure as a superposition of time series, each of said time series representing a temporal contribution for one of said percussive sounds in an audio signal; b) processing said input signal through a spectral analysis technique, so as to select said rhythmic information contained in said input signal; c) constructing said numeric representation of a rhythmic structure of said input signal by combining a plurality of initial time series; and d) reducing said rhythmic information contained in said plurality of time series by analyzing correlations products thereof, thereby extracting a reduced rhythmic information for an item of audio signal. The method may be combined with the step of e) effecting a distance measure between the items of audio signal on the basis of said reduced rhythmic information, whereby an item of audio signal having similar rhythm is selected.