Color enhancement
US4647963A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 9, 1985 |
| Grant date | Mar 3, 1987 |
| Priority date | — |
| Expiry date | Sep 9, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/6027
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Methods of electronically enhancing one or more color components (C, Y, M) which together represent the chromatic components of a pixel of an image are described. The methods comprise subtracting from each color component respective quantities which when combined correspond to a grey level (4) to generate reduced color components. These reduced color components are then multiplied by a factor and the modified reduced color components are then added back to the subtracted quantities or to the original color components to generate enhanced color components (13,14), whereby the factor is chosen such that the hue of the original pixel is not substantially changed after enhancement. In one method, the magnitude of the maximum reduced color component is determined and a factor is chosen which is related to the determined magnitude. In another method, the color components are ranked in order of magnitude and compared to derive two equivalent color component values. The magnitude of the maximum equivalent color component is determined and the factor chosen is related to the determined magnitude of a maximum equivalent color component.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.