Pitch modification method by glottal closure interval extrapolation
US6125344A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 21, 1998 |
| Grant date | Sep 26, 2000 |
| Priority date | — |
| Expiry date | Aug 21, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L21/013
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to an improved pitch modification method by glottal closure interval extrapolation. It is an object of the present invention to modify pitches of speech signals by the glottal closure interval extrapolation and to maintain quality of the modified speech, when concatenating original speech segments to synthesize speech. An input speech signal is converted into a digital speech signal. A glottal closure interval is detected in the digital speech signal so as to estimate vocal tract parameters by using pitch synchronous analysis. Vocal tract characteristic signals of the glottal closure interval and glottal characteristic signals of a glottal open interval are separated from each other according to the detected glottal closure interval. The separated vocal tract characteristic signals are extrapolated and reduced to a desired pitch length by the estimated vocal tract parameter. The extrapolated and reduced vocal tract characteristic signals are overlapped and added to the separated glottal characteristic signal so as to generate a synthetic speech signal which varies in a desired pitch length.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.