Method and apparatus for processing picture image signals
US4845550A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 11, 1986 |
| Grant date | Jul 4, 1989 |
| Priority date | — |
| Expiry date | Sep 11, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/6075
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and process for processing picture image signals detects color separation signals of a color original image and then respectively converts these color separation signals into digital color separation signals. These digital color separation signals are then multiplied by predetermined coefficients and the results of these multiplications are sequentially accumulated for equalizing the levels of the digital color separation signals at a grey point of the original image so as to thereby obtain digital color separation signals which are converted to equivalent neutral densities. Hue signals of yellow, green, cyan, blue, magenta, and red which divide a color space into six hues are obtained from the digital color separation signals which are converted to the equivalent neutral densities. The hue signals are multiplied by predetermined color correction coefficients and the results thereof accumulated for color correction signals on yellow, magenta, and cyan. The digital color separation signals which are converted to the equivalent neutral densities are added to the color correction signals so as to thereby obtain selective color correction signals for recording the original ima…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.