Noise suppression based on bark band wiener filtering and modified doblinger noise estimate
US7492889B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 23, 2004 |
| Grant date | Feb 17, 2009 |
| Priority date | — |
| Expiry date | Aug 10, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L21/0216
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In a noise suppresser, an input signal is converted to frequency domain by discrete Fourier analysis and divided into Bark bands. Noise is estimated for each band. The circuit for estimating noise includes a smoothing filter having a slower time constant for updating the noise estimate during noise than during speech. The noise suppresser further includes a circuit to adjust a noise suppression factor inversely proportional to the signal to noise ratio of each frame of the input signal. A noise estimate is subtracted from the signal in each band. A discrete inverse Fourier transform converts the signals back to the time domain and overlapping and combined windows eliminate artifacts that may have been produced during processing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.