Accession Number:

AD0639964

Title:

SYNTHETIC SPEECH STUDY.

Descriptive Note:

Final rept. 1 Jul 65-30 Jun 66,

Corporate Author:

PHILCO CORP BLUE BELL PA

Personal Author(s):

Report Date:

1966-06-30

Pagination or Media Count:

251.0

Abstract:

The report describes a technique to automatically evaluate the intelligibility of speech transmitted over a communication channel. The technique is called CORODIM Correlation Of the Recognition Of Degradation with Intelligibility Measurements. It transmits a test signal composed of speech-like sounds representative of phoneme consonants, and measures, by means of spectral channel analysis, the degradation suffered by each of the test signal constituents. The degradation manifests itself as an effective noise spectrum which is measured and matched to one of a library of reference noise spectra. By means of the spectrum matching operation and a measurement of signal-to-noise ratio each constituent sound of the test signal is assigned a probability of recognition. These values are weighted by phoneme probability of occurrence factors, summed, and normalized to obtain a score representative of word intelligibility based on either initial or final consonant recognition of CVC-type words. CORODIM evaluates scores for both initial and final consonants and takes their product for the overall word intelligibility score. The part of the CORODIM technique following the spectral analysis operation was computer simulated. The technique was checked against word articulation scores under identical speech link conditions. Two types of speech degradations were considered. The first was additive noise having the same spectral characteristics as that used in deriving the library of phoneme recognition probability data. The second type was degradation produced under laboratory simulated speech link conditions. Author

Subject Categories:

  • Linguistics
  • Voice Communications

Distribution Statement:

APPROVED FOR PUBLIC RELEASE