Sam Roweis, Ph.D.
Assistant Professor
Department of Computer Science
University of Toronto
MIT CSAIL

"A Segment-Based Probabilistic Generative Model of Speech"

Abstract:
Although processing speech signals directly in the time domain has a bad reputation, a clean speech wave exhibits a lot of amazing structure. I'll talk about a radical approach to speech processing which operates purely in the time domain and breaks the speech into "atomic units" by identifying waveform samples at the boundaries between glottal pulse periods (in voiced speech) or at the boundaries of unvoiced segments. An efficient algorithm for inferring these boundaries and estimating the average spectra of voiced and unvoiced regions is derived from a simple probabilistic generative model. Results are presented on pitch tracking, voiced/unvoiced detection and timescale modification; all these tasks and several others can be performed using the single segmentation provided by inference in the model.