INFORMATION PROCESSING METHOD, INFORMATION PROCESSING APPARATUS, PROGRAM AND MEDIUM

Abstract

A patch image generating section 101 generates a patch image by resolving the RGB space into an arbitrary number of steps, and by converting into a CMYK space via an LUT. A patch image calorimetric section 102 outputs the patch image onto a recording medium via a printer, and carries out colorimetry of the output image with a calorimeter. As calorimetric values, calorimetric values represented in an L*a*b* space independent of the RGB space and CMYK space are obtained. A linear space generating section 104 calculates ideal spatial distribution in the color space of the LUT according to the calorimetric values supplied. A color separation evaluation value calculating section 105 compares the ideal spatial distribution in the color space of the LUT with actual measurement data of the LUT. According to the compared results, color separation evaluation values are calculated from differences between the ideal value and actual measurement values.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing an entire configuration of a color separation evaluation system of a color printer of a first embodiment in accordance with the present invention;

FIG. 2 is a view showing an example of a color separation evaluation system in individual embodiments in accordance with the present invention;

FIG. 3 is a block diagram showing individual modules of the system shown in FIG. 2;

FIG. 4 is a flowchart illustrating the operation of the color separation evaluation and modification of the first embodiment in accordance with the present invention;

FIG. 5 is a block diagram showing an entire configuration of a color separation evaluation system of a color printer of a second embodiment in accordance with the present invention;

FIG. 6 is a flowchart illustrating the operation of the color separation evaluation and modification of a third embodiment in accordance with the present invention;

FIG. 7 is a block diagram showing an entire configuration of a color separation evaluation system of a color printer of the third embodiment in accordance with the present invention;

FIG. 8 is a diagram illustrating a target point calculating method in the embodiment in accordance with the present invention;

FIG. 9 is a diagram illustrating another target point calculating method in the embodiment in accordance with the present invention; and

FIG. 10 is a diagram illustrating a linear space in the embodiment in accordance with the present invention.

Claims

1. An information processing apparatus for a data converting section for converting data of a first color space to data of a second color space, said information processing apparatus comprising: patch image generating section for resolving the first color space into a plurality of steps, and for generating, by using said data converting section, patch image data composed of color data in the second color space corresponding to color data of the individual steps after resolving;output section for outputting onto a recording medium a patch image corresponding to the patch image data generated;calorimetric section for carrying out colorimetry of the patch image output onto the recording medium by said output section, and for outputting measured data in a third color space independent of the first color space and the second color space;evaluation reference space generating section for extracting reference point data from the measured data output, and for calculating, by using the reference point data, coordinate data of spatial distribution points corresponding to an evaluation reference in the third color space corresponding to a remainder of the measured data; andcolor separation evaluation value calculating section for calculating color separation evaluation values from differences between the measured data and the coordinate data of the spatial distribution points corresponding to the evaluation reference in the third color space calculated, the coordinate data corresponding to the color data of the individual steps.

2. The information processing apparatus as claimed in claim 1, wherein the reference points are white, black and primaries of primary colors and secondary colors of said output section, and the coordinate data of the spatial distribution points corresponding to the evaluation reference in the third color space calculated are determined such that the gradation between the primaries become linear with respect to appropriate one of lightness, chroma and hue.

3. The information processing apparatus as claimed in claim 1, further comprising gamma space adjusting section, wherein said gamma space adjusting section adjusts, in accordance with a gamma value of lightness provided by said data converting section, the coordinate data of the spatial distribution points corresponding to the evaluation reference in the third color space calculated, and supplies to said color separation evaluation value calculating section.

4. The information processing apparatus as claimed in claim 1, further comprising calorimetric value mapping section and calorimetric value remapping section, wherein said colorimetric value mapping section absorbs curves of axes of primary colors of said output section, carries out mapping onto the coordinate data calculated by said evaluation reference space generating section, and supplies to said color separation evaluation value calculating section; andsaid colorimetric value remapping section carries out remapping of the color separation evaluation values calculated by said color separation evaluation value calculating section in a direction opposite to the mapping in accordance with the axes of the primary colors of said output section.

5. The information processing apparatus as claimed in claim 3, further comprising calorimetric value mapping section and calorimetric value remapping section, wherein said colorimetric value mapping section absorbs curves of axes of primary colors of said output section, carries out mapping onto the coordinate data calculated by said evaluation reference space generating section, and supplies to said gamma space adjusting section; andsaid colorimetric value remapping section carries out remapping of the color separation evaluation values calculated by said color separation evaluation value calculating section in a direction opposite to the mapping in accordance with the axes of the primary colors of said output section.

6. The information processing apparatus as claimed in claim 1, further comprising correcting section for correcting values of said data converting section in accordance with the differences calculated by said color separation evaluation value calculating section.

7. The information processing apparatus as claimed in claim 1, wherein said first color space is an RGB space.

8. The information processing apparatus as claimed in claim 1, wherein said first color space is an L*a*b* space.

9. The information processing apparatus as claimed in claim 1, wherein said first color space is an XYZ space.

10. The information processing apparatus as claimed in claim 1, wherein said first color space is a CMYK space.

11. The information processing apparatus as claimed in claim 1, wherein said second color space corresponds to color materials mounted on said output section.

12. The information processing apparatus as claimed in claim 1, wherein the measured data are L*a*b* values, and the third color space is an L*a*b* space.

13. The information processing apparatus as claimed in claim 1, wherein the measured data is XYZ values, and the third space is an XYZ space.

14. The information processing apparatus as claimed in any one of claims 1-11, wherein the measured data are Jab values, and the third space is a Jab space.

15. An information processing method for a data converting section for converting data of a first color space to data of a second color space, said information processing method comprising: a patch image generating step of resolving the first color space into a plurality of steps, and of generating, by using said data converting section, patch image data composed of color data in the second color space corresponding to color data of the individual steps after resolving;an output step of outputting, by output section, onto a recording medium a patch image corresponding to the patch image data generated;a calorimetric step of carrying out colorimetry of the patch image output onto the recording medium by said output section, and of outputting measured data in a third color space independent of the first color space and the second color space;an evaluation reference space generating step of extracting reference point data from the measured data output, and of calculating, by using the reference point data, coordinate data of spatial distribution points corresponding to an evaluation reference in the third color space corresponding to a remainder of the measured data; anda color separation evaluation value calculating step of calculating color separation evaluation values from differences between the measured data and the coordinate data of the spatial distribution points corresponding to the evaluation reference in the third color space calculated, the coordinate data corresponding to the color data of the individual steps after the resolving.

16. The information processing method as claimed in claim 15, wherein the reference points are white, black and primaries of primary colors and secondary colors of said output section, and the coordinate data of the spatial distribution points corresponding to the evaluation reference in the third color space calculated are determined such that the gradation between the primaries become linear with respect to appropriate one of lightness, chroma and hue.

17. The information processing method as claimed in claim 15, further comprising a gamma space adjusting step between the evaluation reference space generating step and the color separation evaluation value calculating step, wherein the gamma space adjusting step adjusts, in accordance with a gamma value of lightness provided by said data converting section, the coordinate data of the spatial distribution points corresponding to the evaluation reference in the third color space calculated, and supplies to the color separation evaluation value calculating step.

18. The information processing method as claimed in claim 15, further comprising a calorimetric value mapping step between the evaluation reference space generating step and the color separation evaluation value calculating step, and a calorimetric value remapping step after the color separation evaluation value calculating step, wherein the calorimetric value mapping step absorbs curves of axes of primary colors of said output section, carries out mapping onto the coordinate data calculated by the evaluation reference space generating step, and supplies to the color separation evaluation value calculating step; andthe calorimetric value remapping step carries out remapping of the color separation evaluation values calculated by the color separation evaluation value calculating step in a direction opposite to the mapping in accordance with the axes of the primary colors of said output section.

19. The information processing method as claimed in claim 17, further comprising a calorimetric value mapping step between the evaluation reference space generating step and the gamma space adjusting step, and a colorimetric value remapping step after the color separation evaluation value calculating step, wherein the calorimetric value mapping step absorbs curves of axes of primary colors of said output section, carries out mapping onto the coordinated at a calculated by the evaluation reference space generating step, and supplies to the gamma space adjusting step; andthe calorimetric value remapping step carries out remapping of the color separation evaluation values calculated by the color separation evaluation value calculating step in a direction opposite to the mapping in accordance with the axes of the primary colors of said output section.

20. The information processing method as claimed in claim 15, further comprising a correcting step of correcting values of said data converting section in accordance with the differences calculated by the color separation evaluation value calculating step.

21. The information processing method as claimed in claim 15, wherein said first color space is an RGB space.

22. The information processing method as claimed in claim 15, wherein said first color space is an L*a*b* space.

23. The information processing method as claimed in claim 15, wherein said first color space is an XYZ space.

24. The information processing method as claimed in claim 15, wherein said first color space is a CMYK space.

25. The information processing method as claimed in claim 15, wherein said second color space corresponds to color materials mounted on said output section.

26. The information processing method as claimed in claim 15, wherein the measured data are L*a*b* values, and the third color space is an L*a*b* space.

27. The information processing method as claimed in claim 15, wherein the measured data is XYZ values, and the third space is an XYZ space.

28. The information processing method as claimed in claim 15, wherein the measured data are Jab values, and the third space is a Jab space.

29. A program for causing a computer to execute the steps of the information processing method as defined in any one of claims 15-28.

30. A computer readable medium recording the program as defined in claim 28.

31. An information processing method for calculating an evaluation value of a data converting section for converting data of a first color space to data of a second color space, said information processing method comprising: an input step of resolving the first color space into a plurality of steps, of generating, by using said data converting section, patch image data composed of color data in the second color space corresponding to color data of the individual steps after resolving, and of inputting measured data in a third color space, the measured data obtained by carrying out colorimetry of a generated patch image;an evaluation reference space generating step of extracting reference point data from the measured data, and for calculating, by using the reference point data, coordinate data of spatial distribution points corresponding to an evaluation reference in the third color space corresponding to a remainder of the measured data; andan evaluation value calculating step of calculating the evaluation value of said data converting section from differences between the measured data and the coordinate data of the spatial distribution points corresponding to the evaluation reference in the third color space calculated, the coordinate data corresponding to the color data of the individual steps.

32. A program for causing a computer to execute the steps of the information processing method as defined in claims 31.

33. A computer readable medium recording the program as defined in claim 32.