Image processing device for modifying tone characteristics of image data
US6125202A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 17, 1999 |
| Grant date | Sep 26, 2000 |
| Priority date | — |
| Expiry date | May 17, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/67
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Tone calculation for conversion from input image data X to produce converted data Y is performed in accordance with a functional formula including at least two of a first-order term of the input image data X, a second-order term of the input image data X, a third-order term of the input image data X, and a fraction term of the input image data X. In another aspect, color conversion from image data R, G and B to produce printing data C, M and Y by generating complementary color data Ci, Mi and Yi from the image data, determining a minimum value .alpha. and a maximum value .beta. of the complementary color data, generating hue data r, g, b, c, m and y from the complementary color data, the minimum value and the maximum value, generating predetermined matrix coefficients, and determining printing data C, M and Y in accordance with a predetermined matrix calculation using the minimum value, the hue data, and the matrix coefficients.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.