Audio decoding apparatus and method for band expansion with aliasing adjustment
US7069212B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Sep 11, 2003 |
| Grant date | Jun 27, 2006 |
| Priority date | — |
| Expiry date | Sep 11, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/0204
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An audio decoding apparatus decodes high frequency component signals using a band expander that generates multiple high frequency subband signals from low frequency subband signals divided into multiple subbands and transmitted high frequency encoded information. The apparatus is provided with an aliasing detector and an aliasing remover. The aliasing detector detects the degree of occurrence of aliasing components in the multiple high frequency subband signals generated by the band expander. The aliasing remover suppresses aliasing components in the high frequency subband signals by adjusting the gain used to generate the high frequency subband signals. Thus occurrence of aliasing can be suppressed and the resulting degradation in sound quality can be reduced, even when real-valued subband signals are used in order to reduce the number of operations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.