Encoder/decoder for multidimensional sound fields
US5583962A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 1992 |
| Grant date | Dec 10, 1996 |
| Priority date | — |
| Expiry date | Sep 4, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04H20/91
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Two or more audio channels (i.e.--stereo, 4-channel surround, etc.) are each divided into frequency subbands to be coarsely quantized. An adaptive bit allocation scheme is then applied to subbands which are combined across channels such that equivalent subbands (i.e.--same frequency band) from each channel are grouped together to form a steered subband. The power from each subband is averaged across the channels to form a steered subband level. Bits are conserved by forming a vector in which each channel is represented by the difference between the steered subband level (average) and the actual subband level. Subbands which are not steered are represented by the coarse quantization and are considered unsteered channel subbands. Subbands which are steered are represented by vectors and are considered composite channel subbands. Vectors may be represented using a lookup table and the steered subband levels may be calculated using alternatives such as a peak level rather than an average.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.