Method and audio noise suppressor using nonlinear gain smoothing for reduced musical artifacts
US10043530B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 8, 2018 |
| Grant date | Aug 7, 2018 |
| Priority date | — |
| Expiry date | Feb 8, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2499/11
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A noise suppressor has a band extractor to separate signal by frequency band; and per-band units for each of band including noise estimator and SNR computation units. The per-band unit has a histogrammer to give histograms of current and past SNRs, and a gain-curve updater computes gain curves from the histogram. Gain curves are used to determine raw gains from current SNRs, raw gain is filtered and controls a variable gain unit to provide band-specific gain-adjusted, signals that are recombined into a noise-reduced frequency-domain output. Raw gain filtering may include finite-impulse-response filtering and weighted averaging of intermediate gains of a current and adjacent-band per-band unit. The method includes separating an input into frequency bands, estimating in-band noise, and deriving a band SNR. Then, histogramming the SNR and updating a gain curve from the histogram, and finding a raw gain using the gain curve and current SNR.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.