Image processing apparatus, image processing method, and storage medium for color matching

• US 6,897,988 B1
• Filed: 07/27/2000
• Issued: 05/24/2005
• Est. Priority Date: 07/28/1999
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Matsuoka, Hirochika, Saito, Kazuhiro, Makita, Takeshi
• Primary Examiner(s): Coles, Edward
• Assistant Examiner(s): Gibbs, Heather D.
• Application Number:
  US09/624,376
• Time in Patent Office: 1,762 Days
• Field of Search: 358/515, 358/1.8, 358/505, 358/523, 358/1.13, 358/1.15, 358/518, 358/525, 358/522, 358/1.9, 358/500, 382/167
• US Class Current: 358/515
• CPC Class Codes: H04N 1/6072 adapting to different types of images, e.g. characters, graphs, black and white image portions

Abstract

An image processing apparatus comprises a color matching processing unit for performing color matching processing according to color reproduction characteristics of input and output devices, a color separation unit for separating image data subjected to the color matching processing, into color components corresponding to recording agents used by the output device, and a control means for controlling a method of the color matching processing and a method of the image data separation, according to a kind of input image. Thus, it is possible to perform the color matching processing and the color component separation according to the kind of input image, thereby realizing the color matching in consideration of how to use the recording agents and the satisfactory color matching according to a human'"'"'s sight characteristic.

Claims

1. An image processing apparatus comprising:

color matching processing means for performing a color matching processing of mapping an input color signal into a color reproduction range of an output apparatus;

color separation means for separating image data, subjected to the color matching processing, into color components corresponding to recording agents used by the output apparatus;

setting means for setting a kind of input image;

control means for controlling a method of the color matching processing and a method of the image data separation, according to the kind of input image set by said setting means;

synthesis means for generating a lookup table by synthesizing output of said color matching means and said color separation means, both controlled by said control means; and

image processing means for converting the input color signal using the generated lookup table.

2. An apparatus according to claim 1, wherein said control means sets a UCR (under color removal) quantity used by said color separation means, according to the kind of input image set by said setting means.

3. An apparatus according to claim 1, wherein said control means sets a UCR quantity used a kind of input apparatus, a profile corresponding to the kind of output apparatus, and a kind of a recording sheet used by the output apparatus.

4. An apparatus according to claim 1, wherein the kind of input image includes a photograph and a graphic.

5. An apparatus according to claim 1, wherein said image processing means performs a multidimensional interpolation processing.

6. An image processing method comprising:

a color matching processing step, of performing a color matching processing of mapping an input color signal into a color reproduction range of an output apparatus;

a color separation step, of separating image data, subjected to the color matching processing, into color components corresponding to recording agents used by the output apparatus;

a setting step, of setting a kind of input image;

a control step, of controlling a method of the color matching processing and a method of the image data separation, according to the kind of input image set in said setting step;

a synthesis step, of generating a lookup table by synthesizing output of said color matching processing step and said color separation step, both controlled in said control step; and

an image processing step, of converting the input color signal using the generated lookup table.

7. An image processing method comprising:

an obtaining step, of obtaining a color matching processing condition to realize color matching between a first apparatus and a second apparatus; and

a generating step, of generating a multidimensional table based on the color matching processing condition obtained in said obtaining step,

wherein the color matching processing condition of mapping a color reproduction range of the first apparatus to a color reproduction range of the second apparatus is obtained based on an equal-interval hue line of the Atlas of the Munsell Color System,

wherein the color matching processing condition of each plural representative colors is independently obtained, and

wherein the mapping condition concerning a color other than the plural representative colors is obtained based on the color matching processing condition obtained for the plural representative colors.

8. A method according to claim 7, wherein

an achromatic-color target value is set for each of the plural representative colors, and

the color matching processing condition is based on the achromatic-color target value.

9. A method according to claim 8, wherein the obtained color matching processing condition is set as the color matching processing condition used when a kind of input image is a photograph.

10. A method according to claim 8, wherein the plural representative colors are red, green, blue, cyan, magenta and yellow.

11. A method according to claim 7, wherein the color matching processing condition for one of the plural representative colors corresponding to a recording agent used in the second apparatus is obtained based on a reproduction line of the recording agent used in the second apparatus.

12. A storage medium which stores a program for executing an image processing method, said program comprising:

code for an obtaining step, of obtaining a color matching processing condition to realize color matching between a first apparatus and a second apparatus; and

code for a generating step, of generating a multidimensional table based on the color matching processing condition obtained in said obtaining step,

wherein the color matching processing condition of mapping a color reproduction range of the first apparatus to a color reproduction range of the second apparatus is obtained based on an equal-interval hue line of the Atlas of the Munsell Color System,

wherein the color matching processing condition of each plural representative colors is independently obtained, and

wherein the mapping condition concerning a color other than the plural representative colors is obtained based on the color matching processing condition obtained for the plural representative colors.

13. An image processing method of mapping an input color signal into a color reproduction range of an output device, said method comprising:

a providing step, of providing a hue line of the Atlas of the Munsell Color System;

a setting step, of setting a target color in regard to each of plural representative colors; and

a mapping step, of mapping a color signal outside the color reproduction range of the output device into the color reproduction range by using the hue line of the Atlas of the Munsell Color System, provided in said providing step, and the target color set in said setting step, both corresponding to the color signal outside the color reproduction range of the output device.

14. A storage medium which stores a program for executing an image processing method of mapping an input color signal into a color reproduction range of an output device, said program comprising:

code for a providing step, of providing a hue line of the Atlas of the Munsell Color System;

code for a setting step, of setting a target color in regard to each of plural representative colors; and

code for a mapping step, of mapping a color signal outside the color reproduction range of the output device into the color reproduction range by using the hue line of the Atlas of the Munsell Color System, provided in said providing step, and the target color set in said setting step, both corresponding to the color signal outside the color reproduction range of the output device.

15. An image processing apparatus comprising:

an obtaining unit adapted to obtain a color matching processing condition to realize color matching between a first apparatus and a second apparatus; and

a generating unit adapted to generate a multidimensional table based on the color matching processing condition obtained by said obtaining unit;

wherein the color matching processing condition of mapping a color reproduction range of the first apparatus to a color reproduction range of the second apparatus is obtained based on an equal-interval hue line of the Atlas of the Munsell Color System,

wherein the color matching processing condition of each plural representative colors is independently obtained, and

wherein the mapping condition concerning a color other than the plural representative colors is obtained based on the color matching processing condition obtained for the plural representative colors.

16. An image processing apparatus for mapping an input color signal into a color reproduction range of an output device, said apparatus comprising:

a providing unit adapted to provide a hue line of the Atlas of the Munsell Color System;

a setting unit adapted to set a target color in regard to each of plural representative colors; and

a mapping unit adapted to map a color signal outside the color reproduction range of the output device into the color reproduction range by using the hue line of the Atlas of the Munsell Color System, provided by said providing unit, and the target color set by said setting unit, both corresponding to the color signal outside the color reproduction range of the output device.

17. An image processing apparatus comprising:

a color matching processing unit adapted to perform a color matching processing of mapping an input color signal into a color reproduction range of an output apparatus;

a color separation unit adapted to separate image data, subjected to the color matching processing, into color components corresponding to recording agents used by the output apparatus;

a setting unit adapted to set a kind of input image;

a control unit adapted to control a method of the color matching processing and a method of the image data separation, according to the kind of input image set by said setting unit,

a synthesis unit adapted to generate a lookup table by synthesizing output of said color matching unit and said color separation unit, both controlled by said control unit; and

a image processing unit adapted to convert the input color signal using the generated lookup table.