Multipulse LPC speech processing arrangement
US4701954A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 16, 1984 |
| Grant date | Oct 20, 1987 |
| Priority date | — |
| Expiry date | Mar 16, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/10
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A multipulse-code approximation of of one frame of a predictive residual signal may lose the frame-to-frame redundancy. Accordingly, pitch redundancy removal during the iterative process of forming the multipulse sequence, rather than frame-to-frame code comparison, provides reduction of excitation signal bit rate, substantially independent of voice pitch. A speech pattern predictive coding arrangement includes forming a prescribed format multipulse excitation signal for each successive time frame of the pattern. The multipulse excitation signal corresponds to the frame predictive residual. The redundancy in the multipulse excitation signal is reduced by forming a signal representative of the similarities between the current frame speech pattern and the speech pattern of preceding frames and removing such similarities from the multipulse excitation signal. Advantageously, the bit rate of the multipulse excitation signal is reduced and the excitation signal is rendered substantially independent of voice pitch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.