Automatic white balance technique
US7146040B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 2002 |
| Grant date | Dec 5, 2006 |
| Priority date | — |
| Expiry date | Oct 11, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/88
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and a system for an automatic white balancing of color images being exposed to different illuminants have been achieved. The color information from the sensor color channels is measured and averaged over all pixels belonging to each of the colors of the color array used. The result is equivalent to what color a 1-pixel camera would see if pointed to the same scene. From this “statistical pixel” the ratios of the colors involved are calculated. Pictures taken in different illuminants as e.g. daylight, fluorescent light or incandescent light can then be separated due to their location in different categories in a space defined by said ratios of the colors involved. Each category has predefined white balance factors, which are applied to the image now.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.