LPC-harmonic vocoder with superframe structure
US7315815B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 22, 1999 |
| Grant date | Jan 1, 2008 |
| Priority date | — |
| Expiry date | Sep 22, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/087
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An enhanced low-bit rate parametric voice coder that groups a number of frames from an underlying frame-based vocoder, such as MELP, into a superframe structure. Parameters are extracted from the group of underlying frames and quantized into the superframe which allows the bit rate of the underlying coding to be reduced without increasing the distortion. The speech data coded in the superframe structure can then be directly synthesized to speech or may be transcoded to a format so that an underlying frame-based vocoder performs the synthesis. The superframe structure includes additional error detection and correction data to reduce the distortion caused by the communication of bit errors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.