Color cross reference selection system and method

• US 6,944,334 B2
• Filed: 02/01/2001
• Issued: 09/13/2005
• Est. Priority Date: 02/01/2001
• Status: Active Grant

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Mangan, Joseph, Piatt, Michael J., Wozniak, Terry
• Primary Examiner(s): Mehta, Bhavesh M.
• Assistant Examiner(s): Hung, Yubin
• Application Number:
  US09/775,454
• Publication Number:
  US 20020102019A1
• Time in Patent Office: 1,685 Days
• Field of Search: 382/162, 382/165, 382/167, 345589-592, 345600-602, 345606-610, 358501-505, 358518-520, 358/525
• US Class Current: 382/167
• CPC Class Codes: H04N 1/6058 Reduction of colour to a range of reproducible colours, e.g. to ink- reproducible colour gamut

Abstract

A system and method are proposed for the printing of all possible colors, including all permutations of primary inks used to make processed colors, in equal increments and of a size easily measurable with a device that will convert the colors into standard color coordinates. These colors are categorized and used to determine the ability of the output device to reproduce a source color. Each color printed within the gamut of an output device is identified and correlated to independent color coordinates. The primary color recipe necessary to reproduce a reference color within the gamut of the output device is identified. The magnitude of deviation of out of gamut source colors is determined, and the closest in gamut colors are specified through methods of interpolation and nearest neighbor. Furthermore, the alteration in gamut size can be predicted based upon image manipulation processes associated with the workflow. Source colors can be correlated to the altered destination gamut in order to determine the recipe of in gamut colors. An extension of this functionality teaches a method for determining the type, and the extent, of pre-process workflow alterations necessary to maintain or eliminate a source color from the color set of the output device. A set of source colors is correlated to a companion set of the output device in gamut colors, by dependent interpolated adjustment of the set with regard to hue, saturation, and lightness, rather than an absolute value nearest match.

Claims

1. A method for selecting a cross reference color match for outputting to an output device, the method comprising the steps of:

a. identifying a full color gamut of the output device;

b. reducing the full color gamut to a first reduced color gamut;

c. comparing a source color to the first reduced color gamut and the full color gamut to determine a value that is closest to the source color in each gamut;

d. determining if the value is outside the reduced gamut, but inside the full color gamut; and

e. forming a second reduced gamut that is larger in size than the first reduced gamut.

2. A method as claimed in claim 1 wherein the step of determining if the value is outside the reduced gamut, but inside the full color gamut comprises the step of comparing a modified source color and the reduced destination gamut.

3. A method as claimed in claim 1 further comprising the step of comparing the source color against the full color gamut of the output device to determine a closest match between the source color and the full color gamut.

12. A system using the method of claim 1 further comprising the step of correlating an individual color or a set of source colors with an appropriate individual or set of destination colors comprising:

a database of at least one destination color gamut;

means for applying predictive alteration of the at least one destination color gamut;

means for interpolating the database of at least one destination color gamut and predictive alteration of the at least one destination color gamut based on digital data manipulation processes, to determine a closest match between the individual color or set of source colors and the individual or set of destination colors.

13. A system as claimed in claim 12 wherein the matching of an individual color or a set of source colors is applicable to any destination device.

4. A method for identifying a primary color recipe necessary to reproduce a reference color within a gamut of an output device comprising the steps of:

a. using image data to modify the gamut of the output device using image processing;

b. using the modified gamut as a basis for cross-correlation to the reference color by comparing the modified gamut and the reference color;

c. determining magnitude of deviation of out of gamut source colors; and

d. specifying a closest match in gamut color.

5. A method as claimed in claim 4 wherein the step of specifying the closest match in gamut color comprises the step of applying a nearest neighbor evaluation.

6. A method as claimed in claim 4 wherein the step of specifying the closest match in gamut color comprises the step of applying perceptual color algorithms.

7. A method as claimed in claim 4 further comprising the step of printing all possible colors, including all permutations of primary inks used to make processed colors, in equal increments and of a size easily measurable with a devise capable of converting the all possible colors into standard color coordinates.

8. A method as claimed in claim 7 further comprising the steps of:

categorizing the all possible colors; and

using the all possible colors to determine ability of the output device to reproduce a source color.

9. A method as claimed in claim 8 further comprising the step of identifying each color printed within a gamut of the output device.

10. A method as claimed in claim 9 wherein the step of identifying each color printed within a gamut of the output device comprises the step of correlating each color printed to independent color coordinates.

11. A method as claimed in claim 4 further comprising the step of correlating a set of source colors to a companion set of output device in gamut colors using dependent interpolated adjustment of the set of output device in gamut colors with regard to hue, saturation, and lightness.