Frequency band extension in an audio signal decoder
US9911432B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 24, 2014 |
| Grant date | Mar 6, 2018 |
| Priority date | — |
| Expiry date | Jun 24, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/08
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The invention relates to a method for extending the frequency band of an audio signal during a decoding or improvement process comprising a step of decoding or extracting, in a first so-called low frequency band, an excitation signal and coefficients of a linear prediction filter. The method comprises the following steps: —obtaining a signal extended in at least a second frequency band higher than the first frequency band from an oversampled excitation signal extended in at least a second frequency band; —scaling the extended signal by means of a gain defined by subframe on the basis of an energy ratio of a frame and of a subframe; —filtering said scaled extended signal with a linear prediction filter of which the coefficients are derived from the coefficients of the low frequency band filter. The invention also relates to a frequency band extension device implementing the described method and a decoder comprising such a device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.