Method and device for controlling the levels of voiced speech, unvoiced speech, and noise for transmission and reproduction
US5867815A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 15, 1995 |
| Grant date | Feb 2, 1999 |
| Priority date | — |
| Expiry date | Sep 15, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L21/0264
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An encoding apparatus provided at the transmission side includes a low pass filter, a high pass filter, a nonvoice band detecter, a switch and an adder for separating a speech component and a background noise component from an inputted signal. The low pass filter provides a voice band of the speech component and the high pass filter provides a nonvoice band of the speech component. The nonvoice band component is separated from the background noise portion of the output of the high pass filter and re-combined with the voice band to provide the separated speech component. The separated speech component and the background component are individually encoded by a speech encoder and a noise encoder, respectively, and transmitted. In a decoding apparatus at the reception side, the speech component and the background noise component are individually decoded by a speech decoder and a noise decoder, respectively. The decoded speech component and the background noise component are level-adjusted based upon an appropriate level ratio by level controllers, respectively, and then mixed by an adder and outputted as a reproduced signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.