Encoding and decoding of audio signals using complex-valued filter banks
US8255231B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Oct 31, 2005 |
| Grant date | Aug 28, 2012 |
| Priority date | — |
| Expiry date | Mar 17, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/0204
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An encoder (109) comprises a receiver (201) which receives a time domain audio signal. A filter bank (203) generates a first subband signal from the time domain audio signal where the first subband signal corresponds to a non-critically sampled complex subband domain representation of the time domain signal. A conversion processor (205) generates a second subband signal from the first subband signal by subband processing. The second subband signal corresponds to a critically sampled complex subband domain representation of the time domain audio signals. An encode processor (207) then generates a waveform encoded data stream by encoding data values of the second subband signal. The conversion processor (205) generates the second subband signal by direct subband conversion without converting back to the time domain. The invention allows an oversampled subband signal typically generated in parametric encoding to be waveform encoded with reduced complexity. A decoder performs the inverse operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.