Method for the tonal control or adjustment of reproduced color image and picture producing system making use of said method
US5841897A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 1996 |
| Grant date | Nov 24, 1998 |
| Priority date | — |
| Expiry date | May 22, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/60
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method is provided for the control of a color tone during production of a reproduced color image by tonal conversion of a light quantity of each pixel into a halftone. The method includes setting, at a position between a highlight area and a shadow area in a color original image, a color tone control point, defining adjustment conditions at the color tone control point in terms of dot percent values of desired plural color plates. The method also includes introducing a light quantity at the color tone control point, dot percent values of the plates and desired dot percent values set in advance for highlight areas and shadow areas in the plates into a tonal conversion formula to determine values .gamma. for the plates conversion formulas are provided for converting, into dot percent values, light quantities of all pixels ranging from the highlight areas to the shadow areas. The method also includes subjecting light quantities of individual pixels for the plates to tonal conversion and also controlling color tones of the individual pixels for the plates by using the tonal conversion formulas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.