Circuit for performing white balance correction using two color temperature sensors
US4739393A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 3, 1986 |
| Grant date | Apr 19, 1988 |
| Priority date | — |
| Expiry date | Nov 3, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/88
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A circuit for performing white balance correction using two color temperature sensors includes an image sensor for converting an image of an object to a color image signal, a luminance signal/color signal separator for separating an output of the image sensor into a luminance signal and a color signal, and at least one level correction means for correcting a level of the color signal output from the luminance signal/color signal separator, based on a first white balance correction signal or a second white balance correction signal supplied through a switching or disabling means. A first white balance correction signal generator is provided independently of the image sensor and generates the first white balance correction signal correlating to a color temperature of the object. A second white balance correction signal generator generates the second white balance correction signal correlating to the color temperature of the object, based on the luminance signal output from the luminance signal/color signal separator and the color signal having the level corrected by the level correction means.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.