Image processing method and apparatus therefor
US5742296A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1995 |
| Grant date | Apr 21, 1998 |
| Priority date | — |
| Expiry date | Jun 7, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/6058
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image processing method for executing image data conversion between different types of input and output devices having different color reproduction ranges, and an apparatus therefor are disclosed. A device independent color reproduction range is calculated in, e.g., a CIE L*a*b* uniform color space, and a color reproduction range depending on a device such as a binary recording color printer is calculated. Only a saturation is compressed at a compression ratio corresponding to the ratio of the two calculated color reproduction ranges. Thus, when an output device outputs a color image, image qualities (color reproducibilities) of input and output images can be equalized. Even when a color outside the color reproduction range of the output device is to be output, a satisfactory output which preserves gradation characteristics can be obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.