Speech decoding method and apparatus to control the reproduction speed by changing the number of transform coefficients
US5899966A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 1996 |
| Grant date | May 4, 1999 |
| Priority date | — |
| Expiry date | Oct 25, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L25/27
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A signal decoding method and apparatus in which the speech signal reproducing speed is controlled without changing the phoneme or the pitch, in which the apparatus has a data number convertor for converting the number of orthogonal transform coefficients entering a transmission signal input terminal from N to M, an inverse orthogonal transform unit for inverse orthogonal-transforming the M number of the orthogonal transform coefficients obtained by the data number convertor, and a linear predictive coding synthesis filter for performing predictive synthesis based on the short-term prediction residuals obtained by the inverse orthogonal transform unit. For an input signal, short-term prediction residuals are found and are orthogonally transformed to form the orthogonal transform coefficients at a rate of N coefficients per transform unit. The frequency positions of the N transform coefficients may be rearranged to M values by M/N or by oversampling to change N to M. A portable radio terminal embodying the invention is described.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.