Coding device and decoding device of speech signal, coding method and decoding method
US5974375A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 25, 1997 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | Nov 25, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L2019/0005
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A noise codebook selects a code most suitable to the characteristics of an input speech vector from an inside quantification table. Furthermore, a codebook renewal circuit determines a correlative value between a noise code selected by the noise codebook and the input speech vector, subsequently calculates a multiplication value for each of noise codes to generate a renewal code by using the multiplication value with respect to the code selected most frequently by the coding processing at the time of voice. Renewal processing is preformed by replacing a desired code of the codebook with the renewal code. Furthermore, the renewal code is sent to a multiplexing circuit together with a renewal flag value to be sent to a decoding device by using the superfluous bit portion of an unvoice frame.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.