Method and apparatus for searching for combined fixed codebook in CELP speech codec
US7496504B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 2003 |
| Grant date | Feb 24, 2009 |
| Priority date | — |
| Expiry date | Aug 28, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L2019/0013
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Provided are a combined, fixed codebook searching method and apparatus used in a code excited linear prediction (CELP) speech codec. The method is used in a code excited linear prediction (CELP) speech codec, and includes searching for a fixed codebook using a full search method that searches for the fixed codebook at all pulse positions; selecting a fixed codebook searching method by counting the number of users who are accessing a gateway, comparing the number of users with a predetermined threshold, and selecting a proper fixed codebook searching method based on the result of comparison; searching for the fixed codebook using the selected fixed codebook searching method; and checking whether the search for the fixed codebook is complete for all tracks of the CELP speech codec, terminating a routine of searching for the fixed codebook when it is determined the search is complete for all the tracks, and selecting a fixed codebook searching method again in consideration of the number of gateway users when there remains a track to be searched for. Accordingly, a fixed codebook searching method is selected in consideration of the number of users who are accessing a gateway, thereby e…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.