Approach to Computer Speech Recognition by Direct Analysis of the Speech Wave
D. R. Reddy · The Journal of the Acoustical Society of America · 1966
A system for obtaining a phonemic transcription from a connected speech sample entered into the computer by a microphone and an analog-to-digital converter is described. The following features of the system are believed to be new: direct input of the speech signal to the computer without filters or spectrographs; the procedures for segmentation and pitch extraction; the procedure for prosodic parameter determination; and many procedures for phoneme classification. About 30 sounds of 1- to 2-sec duration were analyzed on an IBM-7090-PDP1 disk system. Correct identification of many vowel and consonanted phonemes was achieved for a single cooperative speaker. The time for analysis of each sound varied from 40 to 75 sec. For example, the sentence, “John has a book,” resulted in a phoneme string output “J AA M AE Z EH (B D G) U K.” The results encourage continuing the approach with a more powerful computer to achieve real-time recognition.