Audio decoder with core decoder and surround decoder
US9621990B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 24, 2016 |
| Grant date | Apr 11, 2017 |
| Priority date | — |
| Expiry date | Mar 24, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04S2420/03
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method performed by an audio decoder for reconstructing N audio channels from an audio signal containing M audio channels is disclosed. The method includes receiving a bitstream containing an encoded audio signal having M audio channels and a set of spatial parameters, the set of spatial parameters including an inter-channel intensity difference parameter and an inter-channel coherence parameter. The encoded audio bitstream is then decoded to obtain a decoded frequency domain representation of the M audio channels, and at least a portion of the frequency domain representation is decorrelated with an all-pass filter having a fractional delay. The all-pass filter is attenuated at locations of a transient. A matrixed version of the decorrelated signals are summed with a matrixed version of the decoded frequency domain representation to obtain N audio signals that collectively having N audio channels where M is less than N.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.