Method of determining and storing color printing information
Patent 4481532 Issued on November 6, 1984. Estimated Expiration Date: July 8, 2002. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
A method of determining a set of color correction values includes generating a set of three gray mapper, or gamma, curves and determining from these curves the amount of color correction required to duplicate a sample set of color chips utilizing the particular inks and paper to be used in the final printing process. A set of correction percentages is generated from the correction determination for each of the colors of the set of color chips and these percentages are used in conjunction with input color values to generate corrected color values. The corrected color values may be modified to permit the variable substitution of black ink for a combination of the three colored inks or may be used to compensate for variations in hue of different black inks.
Paper to Technical Association of Graphic Arts entitled "A Proposed Engineering Approach to Color Reproduction" by Irving Pobbaravsky, Jul., 1977