Audio signal coding and decoding methods and apparatus and recording media with programs therefor
US6658382B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 2000 |
| Grant date | Dec 2, 2003 |
| Priority date | — |
| Expiry date | Mar 23, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/0212
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An input signal is time-frequency transformed, then the frequency-domain coefficients are divided into coefficient segments of about 100 Hz width to generate a sequence of coefficient segments, and the sequence of coefficient segments is split into subbands each consisting of plural coefficient segments. A threshold value is determined based on the intensity of each coefficient segment in each subband. The intensity of each coefficient segment is compared with the threshold value, and the coefficient segments are classified into low- and high-intensity groups. The coefficient segments are quantized for each group, or they are flattened respectively and then quantized through recombination.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.