Error diffusion on moderate numbers of output colors
US6483606B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 26, 1998 |
| Grant date | Nov 19, 2002 |
| Priority date | — |
| Expiry date | Aug 26, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/52
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of error diffusion selects colorants, from a plurality of colorants defining a color space, to obtain an actual color which represents a desired color for respective pixels. The actual colors are output by an output apparatus. The process first determines the desired color for a pixel. Next, undercolor removal is performed for the desired color, thereby dividing the desired color into first and second components. A scalar error diffusion is then performed for the first component of the desired color, resulting in a first component of the actual color. A vector error diffusion is performed for the second component of the desired color. The vector error diffusion calculates an error as a negative of a distance in the color space between a closest available colorant in a subset of the plurality of colorants and the desired color. The error is added to the desired color to obtain a second component of the actual color. The first and second components of the actual color are combined to achieve the final actual color. The final actual color is output to a color output apparatus.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.