Method and apparatus for improved quality voice transcoding
US7263481B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 9, 2004 |
| Grant date | Aug 28, 2007 |
| Priority date | — |
| Expiry date | Dec 19, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/173
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for a voice transcoder that converts a bitstream representing frames of data encoded according to a first voice compression standard to a bitstream representing frames of data according to a second voice compression standard using perceptual weighting that uses tuned weighting factors, such that the bitstream of a second voice compression standard to produce a higher quality decoded voice signal than a comparable tandem transcoding solution. The method includes pre-computing weighting factors for a perceptual weighting filter optimized to a specific source and destination codec pair, pre-configuring the transcoding strategies, mapping CELP parameters in the CELP parameter space according to the selected coding strategy, performing Linear Prediction analysis if specified by the transcoding strategy, perceptually weighting the speech using with tuned weighting factors, and searching for adaptive codebook and fixed-codebook parameters to obtain a quantized set of destination codec parameters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.