"Method and device for coding an audio signal by ""forward"" and ""backward"" LPC analysis"
US6327562A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 24, 1999 |
| Grant date | Dec 4, 2001 |
| Priority date | — |
| Expiry date | May 24, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/06
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and device for encoding a digital audio-signal divided into a succession of blocks according to a LPC "forward" and "backward" analysis respectively under a choice criterion. For coding each current block, the choice criterion is established by defining the degree of stationarity of the digital audio-signal according to a stationarity parameter belonging to a maximum and a minimum stationarity range value. An analysis choice value is established from a decision function and this stationarity parameter and thus applied to the digital audio-signal to have this audio digital signal encoded by "backward" LPC filtering for stationary zones. The "forward" and "backward" filtering mode are thus performed in relation to the degree of stationarity of the audio digital signal, the amount of switching from one to the other filtering modes being thus limited.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.