Method and apparatus for speech recognition
US4984275A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 27, 1989 |
| Grant date | Jan 8, 1991 |
| Priority date | — |
| Expiry date | Jul 27, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L25/87
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Power information from an input signal is used to detect the presence of speech. A reference point is established as the moment of detection of the speech. During a period between the reference point and a subsequent point distant from the reference point by a predetermined range, the input signal is linearly changed to a corresponding signal having a predetermined period. Feature parameters are extracted from the signal with the predetermined period. The feature parameters are replaced by preset noise parameters in a portion having no speech component therein. Standard speech patterns of particular preset words are determined and similarities between the extracted feature parameters containing the noise parameters and the standard patterns are calculated and mutually compared. The foregoing steps are performed while the separations are varied within the predetermined range. Similar steps are performed as the reference point is shifted by a unit period, and similarities are calculated and mutually compared. Speech duration is detected by use of movement of the power information. A process end time is determined by use of the speech duration time and a time dependent variation in th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.