Codebook tables for multi-rate encoding and decoding with pre-gain and delayed-gain quantization tables
US6757649B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 2003 |
| Grant date | Jun 29, 2004 |
| Priority date | — |
| Expiry date | Apr 8, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/24
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A speech compression system capable of encoding a speech signal into a bitstream for subsequent decoding to generate synthesized speech is disclosed. The speech compression system optimizes the bandwidth consumed by the bitstream by balancing the desired average bit rate with the perceptual quality of the reconstructed speech. The speech compression system comprises a full-rate codec, a half-rate codec, a quarter-rate codec and an eighth-rate codec. The codecs are selectively activated based on a rate selection. In addition, the full and half-rate codecs are selectively activated based on a type classification. Each codec is selectively activated to encode and decode the speech signals at different bit rates emphasizing different aspects of the speech signal to enhance overall quality of the synthesized speech.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.