Separation of a monaural audio signal into harmonic/percussive components by complementary diffusion on spectrogram

In this paper, we present a simple and fast method to separate a monaural audio signal into harmonic and percussive components, which is much useful for multi-pitch analysis, automatic music transcription, drum detection, modification of music, and so on. Exploiting the differences in the spectrograms of harmonic and percussive components, the objective function is defined in a quadrature form of the spectrogram gradients. Applying the auxiliary function approach to that, simple and fast update equations are derived, which guarantee the decrease of the objective function at each iteration. We show some experimental results by applying our method to popular and jazz music songs.