Noise suppression for low bitrate speech coder
US6122610A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 23, 1998 |
| Grant date | Sep 19, 2000 |
| Priority date | — |
| Expiry date | Sep 23, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L2021/02168
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Noise is suppressed in an input signal that carries a combination of noise and speech. The input signal is divided into signal blocks, which are processed to provide an estimate of a short-time perceptual band spectrum of the input signal. A determination is made at various points in time as to whether the input signal is carrying noise only or a combination of noise and speech. When the input signal is carrying noise only, the corresponding estimated short-time perceptual band spectrum of the input signal is used to update an estimate of an long term perceptual band spectrum of the noise. A noise suppression frequency response is then determined based on the estimate of the long term perceptual band spectrum of the noise and the short-time perceptual band spectrum of the input signal, and used to shape a current block of the input signal in accordance with the noise suppression frequency response.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.