Method and apparatus for speech coding
US7792670B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 14, 2004 |
| Grant date | Sep 7, 2010 |
| Priority date | — |
| Expiry date | Jan 15, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/09
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for prediction in a speech-coding system is provided herein. The method of a 1st order long-term predictor (LTP) filter, using a sub-sample resolution delay, is extended to a multi-tap LTP filter, or, viewed from another vantage point, the conventional integer-sample resolution multi-tap LTP filter is extended to use sub-sample resolution delay. This novel formulation of a multi-tap LTP filter offers a number of advantages over the prior-art LTP filter configurations. Particularly, defining the lag with sub-sample resolution makes it possible to explicitly model the delay values that have a fractional component, within the limits of resolution of the over-sampling factor used by the interpolation filter. The coefficients of such a multi-tap LTP filter are thus largely freed from modeling the effect of delays that have a fractional component. Consequently their main function is to maximize the prediction gain of the LTP filter via modeling the degree of periodicity that is present and by imposing spectral shaping.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.