Long term modeling of phase trajectories within the speech sinusoidal model framework

In this paper, the problem of modeling the trajectory of the phase of speech signal is addressed within the context of the sinusoidal model of speech. A global or long-term model of the trajectory of the phase of the partials is proposed for each entire voiced section of speech, contrary to standard models, which are defined on a frame-by-frame basis. The complete analysis-modeling-synthesis process is presented. We compare two basic long-term models, namely a polynomial and a DCT-based model, with classical (frame-by-frame) interpolation schemes, given that the analysis process is the same in all cases. Promising results are given and the interest of the presented models for speech coding and speech watermarking applications is discussed.