Method and apparatus for automatic brightness and contrast control in an image capture system
US5282063A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 6, 1992 |
| Grant date | Jan 25, 1994 |
| Priority date | — |
| Expiry date | Aug 6, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/76
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus are disclosed for automatic brightness and contrast control in a digital image capture system. A video camera is utilized to scan an image and generate an analog output signal indicative thereof which is utilized to create rows and columns of picture elements. The image is initially scanned utilizing a trial brightness and contrast level and then analyzed to determine the number of saturated picture elements within the scanned image. Thereafter, the brightness and contrast levels are adjusted so that the number of saturated picture elements tends toward a selected small number. In a preferred embodiment of the present invention, the analog output signal is digitized and each picture element created therefrom has a digital value associated therewith. Analysis of the scanned image is accomplished by counting the number of picture elements having a selected digital value. Additionally, once the brightness and contrast levels have been adjusted to substantially achieve the desired number of selected picture elements the signal level is increased by the amount of one digital state at each end of the spectrum to avoid wasting the final digital state at each saturat…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.