Patent · US Expired

Sound analyzing apparatus

US4075423A · kind A · utility

11Cited by
1References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 14, 1977
Grant dateFeb 21, 1978
Priority date
Expiry dateApr 14, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG10L25/00
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Sound Analyzing Apparatus is described for extracting from a speech signal certain basic formant waveforms present in the signal and then examining the formant waveforms to identify the frequency components of the waveforms, using a histogram format in a digital processor. This frequency analysis is accomplished by rectifying the formant waveform, detecting the occurrence of peaks in the resultant waveform and evaluating the time intervals between successive peaks. The apparatus is also biased to reject as invalid those time intervals when peaks of less than a predetermined magnitude occur. Since the formant waveform is typically a succession of damped waves, the frequencies detected are classified into ranges and a running average of the allocation of the frequency components over the ranges is developed over successive sampling periods in order to provide a histogram output illustrative of the final analysis.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.