Method and apparatus for hybrid coding of speech at 4KBPS having phase alignment between mode-switched frames
US6475245B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 5, 2001 |
| Grant date | Nov 5, 2002 |
| Priority date | — |
| Expiry date | Feb 5, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L2025/935
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for encoding speech for communication to a decoder for reproduction of the speech where the speech signal is classified into steady state voiced (harmonic), stationary unvoiced, and “transitory” or “transition” speech, and a particular type of coding scheme is used for each class. Harmonic coding is used for steady state voiced speech, “noise-like” coding is used for stationary unvoiced speech, and a special coding mode is used for transition speech, designed to capture the location, the structure, and the strength of the local time events that characterize the transition portions of the speech. The compression schemes can be applied to the speech signal or to the LP residual signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.