Method and device for preprocessing an acoustic signal upstream of a speech coder
US5644679A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 5, 1995 |
| Grant date | Jul 1, 1997 |
| Priority date | — |
| Expiry date | Jun 5, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/06
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The input acoustic signal is subjected to high-pass filtering. The energy of the high-pass filtered signal is compared with that of the unfiltered signal in order to determine a state of the signal from among a first state for which the energy of the high-pass filtered signal is above a predetermined fraction of the energy of the unfiltered signal and a second state for which the energy of the high-pass filtered signal is below the predetermined fraction of the energy of the unfiltered signal. The high-pass filtered signal subjected to pre-emphasis of the high frequencies is addressed to the input of the coder when the signal is in its second state.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.