Methods and apparatus for generating noise signals from speech signals
US5893056A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 17, 1997 |
| Grant date | Apr 6, 1999 |
| Priority date | — |
| Expiry date | Apr 17, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/06
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In methods and apparatus for generating an LPC-encoded noise signal from an LPC-encoded speech signal, excitation parameters of the LPC-encoded speech signal for a current frame are randomized upon detection of speech in the current frame. For frames in which no speech is detected, LPC coefficients and frame energy for the current frame may be replaced with respective averages calculated over the current frame and a plurality of preceding frames. For frames in which speech is detected, LPC coefficients for the current frame may be replaced with respective averages of LPC coefficients used to replace LPC coefficients of an immediately previous frame. The comfort noise generation technique is particularly suitable for use in echo suppressors for digital cellular radio systems.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.