Fourth European Conference on Speech Communication and Technology

Madrid, Spain
September 18-21, 1995

Second- and Third-Order Wigner Distributions in Hierarchical Recognition of Speech Phonemes

Maria Rangoussi, Flemming Pedersen

Digital Signal Processing Group, Institute for Electronic Systems, Aalborg University, Aalborg, Denmark

In this paper we investigate the use of the time-frequency representation of speech signals, and more specifically of the second- and third-order Wigner distributions, for the hierarchical classification of speech phonemes. We focus on the obstruent rather than the sonorant class of speech phonemes. Our aim is to obtain a new set of recognition features, that are both well-suited to the non-stationary nature of these sounds and robust to noise present when speech is produced under real conditions. A three-level hierarchical classification scheme for obstruent sounds is implemented and tested on real speech data obtained from TIMIT/DARPA, either noise-free or with additive noise, recorded in the interior of a moving car. Satisfactory classification scores are obtained at all three levels, from both distributions; the advantage of third-order over second-order Wigner, however, is marginal, not justifying the extra computations required.

Full Paper

Bibliographic reference.  Rangoussi, Maria / Pedersen, Flemming (1995): "Second- and third-order wigner distributions in hierarchical recognition of speech phonemes", In EUROSPEECH-1995, 259-262.