Method and apparatus in a telecommunications system
US6873954B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 5, 2000 |
| Grant date | Mar 29, 2005 |
| Priority date | — |
| Expiry date | Jan 16, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J3/0632
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Audio artifacts due to overrun or underrun in a playout buffer caused by the sampling rates at a sending and receiving side not being at the same rate are reduced. An LPC-residual is modified on a sample-by-sample basis. The LPC-residual block, which includes N samples, is converted to a block comprising N+1 or N−1 samples. A sample rate controller decides whether samples should be added to or removed from the LPC-residual. The exact position at which to add respective remove samples is either chosen arbitrarily or found by searching for low energy segments in the LPC-residual. A speech synthesiser module then reproduces the speech. By using the proposed sample rate conversion method the playout buffer can be continuously controlled. Furthermore, since the method works on a sample-by-sample basis the buffer can be kept to a minimum and hence no extra delay is introduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.