Reduced real-time processing in stochastic celp encoding
US6044339A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 1997 |
| Grant date | Mar 28, 2000 |
| Priority date | — |
| Expiry date | Dec 2, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/12
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Methods are presented for reducing the processing required for CELP speech encoders which have multiple fixed stochastic codebook subframes corresponding to a single adaptive codebook subframe. The search for the optimum excitation vector in the fixed stochastic codebook requires calculating terms involving correlation of the target speech sample and the fixed stochastic codebook excitation vector as well as energy terms involving only the fixed stochastic codebook excitation vector, and for this class of CELP encoders it is possible to simplify the calculations to reduce their complexity and to make advantageous use of an adaptive energy lookup table. In addition, linear interpolation may be employed to estimate values for the adaptive energy lookup table and further reduce the computational burden.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.