Voice disguise and automatic detection: Review and perspectives

Abstract

This study focuses on the question of voice disguise and its detection. Voice disguise is considered as a deliberate action of the speaker who wants to falsify or to conceal his identity; the problem of voice alteration caused by channel distortion is not presented in this work. A large range of options are open to a speaker to change his voice and to trick a human ear or an automatic system. A voice can be transformed by electronic scrambling or more simply by exploiting intra-speaker variability: modification of pitch, modification of the position of the articulators as lips or tongue which affect the formant frequencies. The proposed work is divided in three parts: the first one is a classification of the different options available for changing one's voice, the second one presents a review of the different techniques in the literature and the third one describes the main indicators proposed in the literature to distinguish a disguised voice from the original voice, and proposes some perspectives based on disordered and emotional speech. © Springer-Verlag Berlin Heidelberg 2007.