Voice transformations through instantaneous complex frequency modifications

The paper presents the possibilities of altering human voice by modifying instantaneous complex frequency (ICF) of the speech signal. The proposed algorithm is based on the factorization of a band-limited, analytic signal into two factors: one fully characterized by its envelope and the other with positive instantaneous frequency (PIF). ICFs of both factors are estimated and modified for different sound effects. The algorithm is tested on short speech utterances and the results of these experiments are presented in the paper.