Auditory Speech Features: The Sounds of English as Processed by a Model of the Ear.
Technical rept. 1 Aug 72-1 Feb 74,
DAYTON UNIV OHIO RESEARCH INST
Pagination or Media Count:
The model of the peripheral auditory system developed at the Neurophysiology Branch in conjunction with a PDP-1120 computer is being used to process and recognize speech by identifying the phonetic features of each sound. This report describes the first stage of research aimed at identification of these features in terms of the auditory model. The English vowels were found to be identifiable with the auditory model by features corresponding quite closely with the well-known spectral formants. Final temporal detail was preserved as well, and this is shown to be a significant advantage for certain sounds characterized by rapid changes in the signal. The model also proved capable of registering such secondary features of vowels as duration, pitch and diphthongalization, which are essential to identification where different speakers and different word contexts are involved. For those consonants studied, the auditory model produced patterns for particular features as specific as those reported for other processing systems, again with the preservation of fine temporal structure. For detection of some consonant features, special purpose circuitry was designed and tested. The report also discusses strategies, based on the phonetic composition of some sounds, for writing integrated phonemic recognition algorithms, and presents the results of some preliminary tests of such algorithms.
- Voice Communications