A nonlinear algorithm for epoch marking in speech signals using poincare maps

A novel nonlinear epoch marking algorithm is proposed for use with voiced speech signals. Epoch detection is useful for speech coding, synthesis and recognition purposes, as it provides both the moment of glottal closure and the instantaneous pitch. Our technique functions entirely in state space, by operating on a three dimensional reconstruction of the speech signal which is formed by embedding. By using the fact that one revolution of this reconstructed attractor is equal to one pitch period, we are able to find points which are pitch synchronous by the use of a Poincare section. Evidently the epoch pulses are pitch synchronous and therefore can be marked. Results using real speech signals are presented to illustrate the performance of the technique.