Pitch Period Determination of Speech Sounds A computer procedure which determines pitch periods by the recognition of the peak structure of the speech waveform is described. Speech sounds were sampled by a microphone and an analog-to-digital converter attached to an interconnected IBM 7090-PDP-1 system. These utterances were recorded at the normal noise level of the computer room but were not band-compressed or phase-distorted in any manner. A sequence of operations defined on the speech wave selects a list of points along the waveform as candidates for pitch markers. These markers are validated by an error detection and correction procedurebout 95 percent of the pitch periods were recognized correctly within 1 to 2 times real-time on the IBM 7090. CACM June,1967 Reddy, D. R. CA670602 JB February 28, 1978 9:42 AM 1590 5 1590 1590 5 1590 1590 5 1590