Analysis relies on selection of peaks of Short Time Fourier Transform
 

Harmonic sounds: peaks of Short Time Fourier Transform
close to a harmonic of local fundamental frequency (f0)
 

Inharmonic sounds: build trajectories of sinusoids with statistically optimal continuity of values (frequency, amplitude and phase) and/or of slopes:

                            hmm (Hidden Markov Model)

Implented in Diphone Sudio

Interpolator 

Morphing 
 

fft-1for real-time system FTS-jMax,
hundreds of arbitrary sinusoidal partials and noise

New research on additive theory

Credits: Ph. Depalle, G. Garcia, R. Woehrman, A. Lefèvre, Schwarz,  P. Chose, N. Schnell, X. Rodet,