Color management system

• US 8,184,349 B2
• Filed: 06/18/2008
• Issued: 05/22/2012
• Est. Priority Date: 06/20/2007
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Yamazoe, Manabu
• Primary Examiner(s): Safaipour, Houshang
• Application Number:
  US12/141,226
• Publication Number:
  US 20080316513A1
• Time in Patent Office: 1,434 Days
• Field of Search: 358/518, 358/1.9, 358/522, 358/523
• US Class Current: 358/518
• CPC Class Codes: H04N 1/6033 using test pattern analysis H04N1/6055 takes precedence

Abstract

The present invention provides a color conversion device that can be applied to a color management system. The color conversion device provides a color conversion device capable of generating a color conversion table used for color reproduction with high precision. The color conversion device generates a color conversion table that describes a correspondence relationship between color data in a first color space and color data in a second color space and corrects the correspondence relationship described in the color conversion table based on calorimetric values of color sample charts obtained by the reading of a plurality of the color sample charts. The color conversion device according to the present invention can correct the output values based on the calorimetric values of the color sample charts.

Claims

1. A color conversion device comprising:

a color conversion table for describing a correspondence relationship between first color data in a first color space and second color data in a second color space; and

a correction component for correcting the correspondence relationship described in the color conversion table based on colorimetric values of a color sample chart obtained by reading a plurality of the color sample charts,

wherein in the color conversion table, specific grid point data of a color space generated from the color sample chart and output values corresponding to the specific grid point data are described based on a color conversion matrix or a mapping that links the first color space to the second color space, and

wherein the specific grid point data, intervals of grid points of which are not uniform, is located in the first color space.

2. The color conversion device of claim 1, wherein the correction component corrects the second color data described in the color conversion table based on the colorimetric values.

3. The color conversion device of claim 1, wherein the first color space is a color space that depends on a device and the second color space is a color space that does not depend on a device.

4. The color conversion device of claim 2, wherein the first color space is a color space that depends on a device and the second color space is a color space that does not depend on a device.

5. The color conversion device of claim 1, wherein the color sample chart indicates a gray region or a specific memory color.

6. The color conversion device of claim 2, wherein the color sample chart indicates a gray region or a specific memory color.

7. The color conversion device of claim 3, wherein the color sample chart indicates a gray region or a specific memory color.

8. The color conversion device of claim 1, wherein the correction component corrects the output values based on the colorimetric values of the color sample chart.

9. A color conversion method comprising the steps of:

generating a color conversion table for describing a correspondence relationship between first color data in a first color space and second color data in a second color space; and

correcting the correspondence relationship described in the color conversion table based on colorimetric values of a color sample chart obtained by reading a plurality of the color sample charts,

wherein the color conversion table describes specific grid point data of a color space generated from the color sample chart and output values corresponding to the specific grid point data, based on a color conversion matrix or a mapping that links the first color space to the second color space, and

wherein the specific grid point data, intervals of grid points of which are not uniform, is located in the first color space.

10. The color conversion method of claim 9, wherein in the correction step, the second color data described in the color conversion table is corrected based on the colorimetric values.

11. The color conversion method of claim 9, wherein the first color space is a color space that depends on a device and the second color space is a color space that does not depend on a device.

12. The color conversion method of claim 10, wherein the first color space is a color space that depends on a device and the second color space is a color space that does not depend on a device.

13. The color conversion method of claim 9, wherein the color sample chart indicates a gray region or a specific memory color.

14. The color conversion method of claim 10, wherein the color sample chart indicates a gray region or a specific memory color.

15. The color conversion method of claim 11, wherein the color sample chart indicates a gray region or a specific memory color.

16. The color conversion method of claim 9, wherein in the correction step, the output values are corrected based on the colorimetric values of the color sample chart.

17. A non-transitory computer-readable recording medium having computer-executable instructions for performing a color conversion method, the method comprising the steps of:

generating a color conversion table for describing a correspondence relationship between first color data in a first color space and second color data in a second color space; and

correcting the correspondence relationship described in the color conversion table based on colorimetric values of a color sample chart obtained by reading a plurality of the color sample charts,

wherein in the color conversion table, specific grid point data of a color space generated from the color sample chart and output values corresponding to the specific grid point data are described based on a color conversion matrix or a mapping that links the first color space to the second color space, and

wherein the specific grid point data, intervals of grid points of which are not uniform, is located in the first color space.

18. A color conversion device comprising:

a generating component constructed to generate a color conversion table for describing a correspondence relationship between first color data in a first color space that depends on a device and second color data in a second color space that does not depend on a device, by using a mapping based on scanned data in the first color space scanned by a scanner and colorimetric data in the second color space performed colorimetry by a colorimeter; and

a correction component constructed to correct a correspondence relationship of specific grid point data and output values corresponding to the specific grid point data described in the color conversion table based on colorimetric values of a color sample chart of gray, memory colors or corporate colors obtained by performing colorimetry of the color sample chart of gray, memory colors or corporate colors, and

wherein the specific grid point data, intervals of grid points of which are not uniform, is located in the first color space.

19. A color conversion method comprising:

generating a color conversion table for describing a correspondence relationship between first color data in a first color space that depends on a device and second color data in a second color space that does not depend on a device, by using a mapping based on scanned data in the first color space scanned by a scanner and colorimetric data in the second color space performed colorimetry by a colorimeter; and

correcting a correspondence relationship of specific grid point data and output values corresponding to the specific grid point data described in the color conversion table based on colorimetric values of a color sample chart of gray, memory colors or corporate colors obtained by performing colorimetry of the color sample chart of gray, memory colors or corporate colors, and

wherein the specific grid point data, intervals of grid points of which are not uniform, is located in the first color space.