A Real-time Equalizer of Harmonic and Percussive Components in Music Signals

In this paper, we present a real-time equalizer to control a volume balance of harmonic and percussive components in music signals without a priori knowledge of scores or included instruments. The harmonic and percussive components of music signals have much different structures in the power spectrogram domain, the former is horizontal, while the latter is vertical. Exploiting the anisotropy, our methods separate input music signals into them based on the MAP estimation framework. We derive two kind of algorithm based on a I-divergence-based mixing model and a hard mixing model. Although they include iterative update equations, we realized the real-time processing by a sliding analysis technique. The separated harmonic and percussive components are finally remixed in an arbitrary volume balance and played. We show the prototype system implemented on Windows environment.