System and method for automatic image saturation, gamma, and exposure correction in a digitizing video capture system
US5265200A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 1, 1990 |
| Grant date | Nov 23, 1993 |
| Priority date | — |
| Expiry date | Nov 1, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/10016
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Analog video data input is received by a video capture system and digitized. From the pels of the captured image, a gray scale level histogram is constructed with the system processor, and normalized to established white-black references similar to the contrast control function at image capture time. Peaks likely attributable to image artifacts are limited. The image processor then performs a second order best fit regression of the histogram from which the image is thereafter corrected. An automatic correction of the image contrast is thereby effected, wherein capture artifacts are reduced while retaining those of the image. In an alternate embodiment, instead of limiting peaks, an iterative best fit is performed, wherein the peaks are weighted in a subsequent best fit pass as a function of their distances from the curve fit from a prior best fit pass.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.