Voice synthesis utilizing multi-level filter excitation
US4890328A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Aug 28, 1985 |
| Grant date | Dec 26, 1989 |
| Priority date | — |
| Expiry date | Aug 28, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/08
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A speech analysis and synthesis system where pitch information for excitation is transmitted during voice segments of speech and pulse excitation or noise excitation is transmitted during unvoiced speech segments along with linear predictive coding (LPC) parameters. The decision of whether to transmit noise excitation or pulse excitation is performed by comparing the variance of the residual to the square of the mean amplitude of the rectified residual for each frame. If the result of this comparison is greater than a threshold value, pulse excitation is utilized otherwise noise excitation is used. The pulse excitation comprises a subset of samples of the LPC residual as determined by the relative amplitudes and spacing of the local maxima in the LPC residual.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.