JP4375130B2 - Color output characteristic correction information calculation apparatus, color output characteristic correction information calculation method, color conversion apparatus, and color conversion method - Google Patents

Description

  The present invention relates to a color output characteristic correction information calculation apparatus and a color output characteristic correction information calculation method for calculating correction information used when approximately correcting the color output characteristic of one output device to the color output characteristic of the other color output device. The present invention also relates to a color conversion apparatus and a color conversion method for approximating output information with correction information.

As a method for approximately correcting a difference in color output characteristics between image output apparatuses (color output apparatuses) having different color output characteristics, a method for adjusting colors by adjusting a gradation reproduction curve (tone curve) is widely used. For example, between printing presses with different color output characteristics, the difference between the two color output characteristics is corrected using an output curve of a film setter, adjustment of the degree of printing during printing, and a CTP (Computer to Plate) curve. . In color matching by such curve correction, a method of correcting a difference in color output characteristics using a graph generally called a Jones diagram is employed.
JACYule, Tsutomu Mawatari, Tatsuro Kunishi, Theory of Color Production, Printing Society Press, February 5, 1971, p.88

  According to this method, the gradation reproduction of the primary color can be matched, but the color tone of the entire image cannot be matched only by matching the gradation reproduction of the primary color. This is considered to be mainly due to the fact that there are almost no primary color regions in an actual natural image, and most of them are composed of secondary colors and higher. In this case, it is necessary to further change the correction curve to correct the difference in color output characteristics. However, there is no clear method for adjusting the curve at this time, and the image output device is actually corrected by correcting the curve little by little. It is necessary to perform a trial and error search for a correction curve that finally produces the closest color tone of the entire image. This operation is not easy, and in addition to the time problem that it takes time to make a decision, it is necessary to actually repeat the output from the image output apparatus. It is possible to adjust the color tone of the entire image by adjusting the correction curve directly without using the Jones diagram to match the primary color. Repeated work was required and similar problems occurred.

  Accordingly, the present invention is made to solve the above-described problems of the conventional technology, and calculates correction information that can correct the color output characteristics between the color output devices in a short time without any effort. It is an object of the present invention to provide a color output characteristic correction information calculation apparatus and a color output characteristic correction information calculation method, and a color conversion apparatus and a color conversion method for approximating output information by correction information.

The present invention has been made to solve the above-described problem. The color output characteristics of a second color output device that performs color output for one color based on a combination of a plurality of color element signal values are described in the second. used when approximating the correction to the color output characteristic of the first color output device for performing color output color based on a combination of the color output device and the color element signal values in the same manner, it converts the color output characteristic of the pre-conversion in the approximation correction A color output characteristic correction information calculation apparatus for calculating correction information indicating a correspondence relationship with a subsequent color output characteristic , wherein the first color output apparatus determines a combination of color element signal values and a combination of the color element signal values. First color output device profile storage means for storing a first color output device profile that associates actual measured values of colors to be output, a combination of color element signal values, and a combination of the color element signal values. Color output device outputs Second color output device profile storage means for storing a second color output device profile in association with actual color values, first evaluation data holding a plurality of combinations of color element signal values, and the first color A first actual value calculation means for calculating an actual value of each color when the first color output device performs color output using the first evaluation data based on the output device profile; and the second evaluation data converted on the basis of the correction information of each combination of color component signal values which holds correspondence between the color output characteristic of the converted color output characteristic of the pre-conversion in the approximate correction different a second evaluation data calculation means for multiple calculated by the correction information, the second evaluation data and said second color output device profile, based on said second color output by the second evaluation data The second actual value calculation means for calculating the actual measurement value of each color when the device outputs a color, the actual measurement value of each color calculated by the first actual measurement value calculation means, and the second actual value calculation means A first color output device that performs output using the first evaluation data and a second color output device that performs output using the second evaluation data based on the relationship between the measured values of the respective colors. The correction information for calculating the second evaluation data when the color output characteristic difference information indicating the difference between the color output characteristics is calculated and the color output characteristic difference information having the smallest value is calculated by the optimization method is calculated. Color output characteristic correction information calculation comprising: correction information for determining the color output characteristic of the second color output device to be approximately corrected to the color output characteristic of the first color output device; and correction information determining means for determining the color output characteristic. Device.

  According to another aspect of the present invention, the color output characteristic correction information calculation apparatus includes a profile reading unit that reads one or both of the first color output apparatus profile and the second color output apparatus profile, and the first color output apparatus. One or both of a profile and a profile generation means for generating either or both of the second color output device profiles are provided.

The present invention also provides a color conversion device that approximates the color output characteristics of one color output device to the color output characteristics of the other color output device, and includes a combination of color element signal values and a combination of the color element signal values. A first color output device profile storage means for storing a first color output device profile in association with an actual color value output by the other color output device, a combination of color element signal values, and the color element A second color output device profile storage means for storing a second color output device profile that associates an actual measured value of the color output by the one color output device with a combination of signal values; and a combination of color element signal values. Based on the plurality of first evaluation data and the other color output device profile, an actual measurement value of each color when the other color output device outputs a color using the first evaluation data is calculated. Based on 1 and measured value calculation means, correction information indicating a correspondence relationship between the color output characteristic of the converted color output characteristics before conversion in the approximation correcting each combination of color component signal values held by the first evaluation data Second evaluation data calculation means for calculating a plurality of second evaluation data converted in accordance with a plurality of correction information in which the correspondence relationship between the color output characteristics before conversion and the color output characteristics after conversion in the approximate correction is different ; Based on the second evaluation data and the one output device profile, a second actual value calculation for calculating an actual measurement value of each color when the one color output device performs color output by the second evaluation data. And the first evaluation data based on the relationship between the actual measurement value of each color calculated by the first actual measurement value calculation unit and the actual measurement value of each color calculated by the second actual measurement value calculation unit. Calculating color output characteristic difference information indicating a difference in color output characteristics between the other color output device that performs output and the one color output device that performs output using the second evaluation data; The correction information for calculating the second evaluation data when the color output characteristic difference information having the smallest value is calculated by the optimization method, the color output characteristic of the one color output device, and the other color output device. Correction information determining means for determining and correcting the approximate color output characteristics, correction information applying means for applying the specified correction information to the color element signal value of the color output from the one color output device, A color conversion device comprising:

The present invention also provides a color output characteristic of a second color output device that performs color output for one color based on a combination of a plurality of color component signal values, as in the second color output device. The correspondence relationship between the color output characteristics before conversion and the color output characteristics after conversion in the approximate correction is used when approximate correction is performed to the color output characteristics of the first color output device that performs color output of colors based on the combination of A color output characteristic correction information calculation method for a color output characteristic correction information calculation apparatus for calculating correction information, wherein a first color output apparatus profile storage means uses a combination of color element signal values and a combination of the color element signal values. A first color output device profile that associates the actual color values output by the first color output device with each other is stored, and the second color output device profile storage means stores the combination of color element signal values and the color elements For combinations of signal values Thus, a second color output device profile in which the actual color values output by the second color output device are associated with each other is stored, and the first actual value calculation means stores a plurality of combinations of color element signal values. Based on one evaluation data and the first color output device profile, an actual measurement value of each color when the first color output device outputs a color is calculated based on the first evaluation data, and is used for the second evaluation. data calculating means, the second evaluation data converted on the basis of the correction information of each combination of color component signal values held by the first evaluation data, the converted color output characteristic of the pre-conversion in the approximate correction A plurality of correction information having different correspondence relations with the color output characteristics of the second color, and a second actual measurement value calculation unit is configured to perform the second measurement based on the second evaluation data and the second color output device profile. Depending on the evaluation data An actual measurement value of each color when the second color output device outputs a color is calculated, and a correction information determination unit calculates the actual measurement value of each color calculated by the first actual measurement value calculation unit and the second actual measurement value calculation unit. The first color output device that outputs using the first evaluation data based on the relationship between the actual measurement value of each color calculated by the above and the second color that outputs using the second evaluation data Color output characteristic difference information indicating a difference in color output characteristics with the output device is calculated, and the second evaluation data is calculated when the color output characteristic difference information having the smallest value is calculated by the optimization method. The color output characteristic correction information calculation method is characterized in that the correction information is determined as correction information for approximately correcting the color output characteristic of the second color output device to the color output characteristic of the first color output device.

  According to the present invention, in the above-described color output characteristic correction information calculation method, the process of reading one or both of the first color output device profile and the second color output device profile, the first color output device profile, And / or a process of generating either or both of the second color output device profiles.

The present invention also relates to a color conversion method for a color conversion device that approximates the color output characteristics of one color output device to the color output characteristics of the other color output device, wherein the first color output device profile storage means includes: A first color output device profile in which a combination of element signal values and an actual color value output by the other color output device according to the combination of the color element signal values is associated is stored, and a second color output device profile is stored A storage unit stores a second color output device profile in which a combination of color element signal values and an actual measurement value of a color output from the one color output device according to the combination of the color element signal values are associated, 1 actual measurement value calculation means based on the first evaluation data holding a plurality of combinations of color element signal values and the other color output device profile, the other color output device based on the first evaluation data Is the color Calculating a measured value of each color at the time of force, the converted second evaluation data calculating means, each combination of the color element signal values held by the first evaluation data and the color output characteristic before conversion in the approximate correction A plurality of corrections in which the correspondence between the color output characteristics before conversion and the color output characteristics after conversion in the approximate correction is different from the second evaluation data converted based on the correction information indicating the correspondence relation with the color output characteristics of A plurality of values are calculated based on the information , and the second actual value calculation means outputs the color from the one color output device by the second evaluation data based on the second evaluation data and the one output device profile. An actual measurement value of each color at the time, and the correction information determination means, the actual measurement value of each color calculated by the first actual measurement value calculation means, the actual measurement value of each color calculated by the second actual measurement value calculation means, In relation to Accordingly, a difference in color output characteristics between the other color output device that performs output using the first evaluation data and the one color output device that performs output using the second evaluation data. The color output characteristic difference information indicating the second evaluation data when the color output characteristic difference information having the smallest value is calculated by the optimization method, and the one color output device The color output characteristic of the second color output device is determined to be correction information that approximates the color output characteristic of the other color output device, and the correction information application unit uses the specified correction information as the color of the color output by the one color output device A color conversion method characterized by being applied to an element signal value.

  According to the present invention, the first evaluation data is obtained based on the relationship between the actual measurement value of each color calculated by the first actual measurement value calculation unit and the actual measurement value of each color calculated by the second actual measurement value calculation unit. Calculating and optimizing color output characteristic difference information indicating a difference in color output characteristics between the first color output device that performs output using the second color output device that performs output using the second evaluation data The correction information for calculating the second evaluation data when the color output characteristic difference information having the smallest value is calculated by the technique is approximated with the color output characteristic of the second color output device approximated to the color output characteristic of the first color output device. Since the correction information to be corrected is determined, correction information for approximately correcting the color output characteristic of the second color output device to the color output characteristic of the first color output device can be calculated.

  Further, according to the present invention, the color element signal value at the time of color output of one color output device is corrected by using the correction information that the color conversion device can approximate correct to the color output characteristics of the other color output device. The output of one color output device can be corrected without effort to a color close to the color output characteristics of the other color output device.

  A color output characteristic correction information calculation apparatus according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a color output characteristic correction information calculation apparatus according to the embodiment. In this figure, reference numeral 1 denotes a color output characteristic correction information calculation device. The color output characteristic correction information calculation device 1 includes an evaluation data storage unit 11, an evaluation data conversion processing unit (second evaluation data calculation unit) 12, and a first profile storage unit (first color output device profile storage unit). 12, second profile storage unit (second color output device profile storage unit) 13, first colorimetric value calculation unit (first actual measurement value calculation unit) 15, second colorimetry value calculation unit (second actual measurement value calculation unit) ) 16 and a correction information determination unit (correction information determination means) 17.

  The evaluation data storage unit 11 stores evaluation data (first evaluation data) that holds a plurality of combinations of color element signal values used for color output. FIG. 2 is a diagram showing evaluation data. As shown in FIG. 2, specifically, the evaluation data includes C (cyan), M (magenta), Y (yellow), and K (black) colors defined by a color chart called IT8.7 / 3 (ISO12642). Holds combinations of element signal values. Similar to the color chart of IT8.7 / 3 as evaluation data, if each color evenly distributed in the color space is used, a combination of color element signal values for outputting each color is retained, so that various color spaces can be used. The color output characteristic of the second color output device can be approximated to the color output characteristic of the first color output device with respect to the correct color. If a color obtained by collecting only multiplications of specific areas to be optimized is used as evaluation data, optimum correction information can be obtained for the specific areas. If image data actually output by the second color output device is used as evaluation data, optimum correction information can be obtained for the output image itself.

The evaluation data conversion processing unit 12 performs a process of converting the CMYK values of the evaluation data into C′M′Y′K ′ based on the correction information.
FIG. 3 is a diagram showing a spline curve of correction information.
Here, the correction information is a control when the central value of the straight line A in FIG. 3 indicating that the value before conversion of the color element signal value is the same as the value after conversion of the color element signal value is a control point. It is represented by a spline curve in which the color element signal value after conversion corresponding to a point is changed. The correspondence between the color element signal value before conversion and the color element signal value after conversion indicated by the curve represented by the spline curve is correction information. Then, the correction data is generated by the evaluation data conversion processing unit 12 for each color element signal value CMYK, and the evaluation data conversion processing unit 12 converts each CMYK value of the evaluation data based on the correction information. The converted evaluation data (second evaluation data) is calculated.

  The first profile storage unit 13 is a storage unit that stores a profile (hereinafter referred to as a first printing device profile) in which the color output characteristics of the first printing device are described. The first printing apparatus profile includes a combination CMYK value of color element signal values and a colorimetric value (actual measurement value: for example, output from the first printing apparatus when color output is performed using the CMYK value. 6 is a table in which CIELab values are associated with each other. The first printing device profile stored in the first profile storage unit 13 may be read and stored directly by the color output characteristic correction information calculation device 1 from the first printing device, or may be stored in advance via a recording medium. The user may record in the first profile storage unit 13. The color output characteristic correction information calculation device 1 includes a processing unit that generates a first printing device profile. The first profile storage unit 13 stores the first printing device profile generated by the processing unit that generates the first printing device profile. May be recorded.

  The second profile storage unit 14 is a storage unit that stores a profile (hereinafter referred to as a second printing device profile) in which the color output characteristics of the second printing device are described. This second printing device profile also includes a color component signal value combination CMYK value and a colorimetric value (for example, CIELab value) of a color output from the second printing device when color output is performed using the CMYK value. Is a table in which The second printing device profile stored in the second profile storage unit 14 may be read and stored by the color output characteristic correction information calculation device 1 directly from the second printing device, or may be stored in advance via a recording medium. The user may record in the second profile storage unit 14. The color output characteristic correction information calculation device 1 includes a processing unit that generates the second printing device profile, and the second printing device profile generated by the processing unit (profile generation unit) that generates the second printing device profile is the first printing device profile. The two-profile storage unit 14 may record.

  The first colorimetric value calculation unit 15 uses the evaluation data and the first printing device profile to calculate a colorimetric value for each color when the first printing device prints using the evaluation data. In addition, the second colorimetric value calculation unit 16 uses any one of the plurality of converted evaluation data calculated by the evaluation data conversion processing unit 12 and the second printing apparatus profile. A colorimetric value of each color when the second printing apparatus prints using the converted evaluation data is calculated for each of the evaluation data among a plurality of converted evaluation data.

  Then, the correction information determination unit 17 determines the relationship between the colorimetric value of each color calculated by the first colorimetric value calculation unit 15 and the colorimetric value of each color calculated by the second colorimetric value calculation unit 16. Between the first printing device that performs printing using the evaluation data and the second printing device that performs printing using any of the converted evaluation data among the plurality of converted evaluation data. Color output characteristic difference information indicating a difference in color output characteristics is calculated, and the post-conversion evaluation data used when calculating the color output characteristic difference information with the smallest value is specified. The correction information at the time of calculation is determined as correction information for approximately correcting the color output characteristic of the second printing apparatus to the color output characteristic of the first printing apparatus. If the color element signal value CMYK of each color of the image data input to the second printing apparatus is converted using this correction information, the second printing can be performed with a color tone that is approximately similar to that when printing is performed using the first printing apparatus. It can be done with a printing device.

FIG. 4 is a diagram showing an outline of data of the first printing device profile or the second printing device profile.
As shown in FIG. 4, the first printing device profile and the second printing device profile are the first (second) when color output is performed using the combination CMYK value of color element signal values and the value of the CMYK. ) Correlated colorimetric values (for example, CIELab values) of colors output from the printing apparatus.

FIG. 5 is a diagram showing a processing flow of the color output characteristic correction information calculation apparatus.
Next, the processing flow of the color output characteristic correction information calculation apparatus will be described with reference to FIG.
First, the control unit (profile reading unit) of the color output characteristic correction information calculation device 1 reads the evaluation data, the first printing device profile, and the second printing device profile, respectively, and the evaluation data storage unit 11, the first profile. It records in the memory | storage part 13 and the 2nd profile memory | storage part 14 (step S1).
Then, the first colorimetric value calculation unit 15 reads the first printing device profile from the first profile storage unit 13 and reads the evaluation data from the evaluation data storage unit 11. Then, the first colorimetric value calculation unit 15 calculates the colorimetric value of each combination based on the first printing apparatus profile based on the combination of the color element signal values held in the evaluation data (step S2). . At this time, the first printing apparatus profile includes a combination CMYK value of color element signal values and a colorimetric value of a color output from the first printing apparatus when color output is performed using the CMYK value. Since the relationship is held, the colorimetric value of each combination is calculated from the combination of each color element signal value held in the evaluation data by interpolation calculation or the like. Accordingly, when all the evaluation data are combined, that is, when the first printing apparatus prints a color chart called IT8.7 / 3 based on the evaluation data, the colorimetric values for all the colors of the color chart. Will be predicted.

  Further, the evaluation data conversion processing unit 12 converts the evaluation data by using different correction information (curve represented by the spline curve shown in FIG. 3) for each of the color element signal values CMYK. The post-conversion evaluation data is generated (step S3). Here, the evaluation data conversion processing unit 12 can generate a plurality of correction information in accordance with the movement width of the straight control points shown in FIG. 3, and accordingly generates correction information indicating various curves. Then, a plurality of post-conversion evaluation data is generated by a combination of correction information corresponding to each of CMYK.

  Then, the second colorimetric value calculation unit 16 reads a plurality of post-conversion evaluation data from the evaluation data conversion processing unit 12, and also reads the second printing device profile from the second profile storage unit 14, and the second printing device. However, when the color chart is printed using the post-conversion evaluation data, the colorimetric value of each combination included in the color chart is calculated (step S4). That is, the second printing apparatus calculates, for each color chart printed by each of the plurality of post-conversion evaluation data, a plurality of combinations of colorimetric values held by the color chart. This process is the same process as the first colorimetric value calculation unit 15.

  Next, the correction information determination unit 17 calculates the colorimetric values for each color of the evaluation data calculated by the first colorimetric value calculation unit 15 and the converted evaluation data calculated by the second colorimetric value calculation unit 16. The difference from the colorimetric value for each color is calculated for each color held in the evaluation data and the converted evaluation data. Then, a value obtained by averaging the total by the number of colors is calculated, and this value is used as color output characteristic difference information (step S5). Then, the correction information determination unit 17 calculates color output characteristic difference information for each of a plurality of post-conversion evaluation data. Then, the post-conversion evaluation data when the color output characteristic difference information having the smallest value is calculated is specified (step S6). Further, the correction information obtained by calculating the specified conversion evaluation data is acquired from the evaluation data conversion processing unit 12. Then, the correction information determination unit 17 uses the correction information acquired from the evaluation data conversion processing unit 12 as the correction information that can most approximately correct the color output characteristic of the second printing apparatus to the color output characteristic of the first printing apparatus. Determine (step S7).

Note that the color output characteristic difference information calculation method is not limited to the above-described method, and may be calculated by another method.
For example, the evaluation data conversion processing unit 12 generates post-conversion evaluation data, and the colorimetric values of each color calculated by the first colorimetric value calculation unit 15 and the second colorimetric value calculation unit 16 are calculated. Based on the relationship between the colorimetric values of each color, the color output characteristics between the first printing apparatus that outputs using the evaluation data and the second printing apparatus that outputs using the converted evaluation data Correction information for calculating post-conversion evaluation data when the color output characteristic difference information having the smallest value is calculated by the optimization method is calculated. The color output characteristic is determined as correction information that approximates the color output characteristic of the first printing apparatus. As the optimization method, there are methods such as Simplex method, simulated annealing, and brute force method.

Then, the color output is converted by applying the correction information specified by the color output characteristic correction information calculating device 1 to the second printing device profile or applying the correction information to the output image information. Then, color output processing approximated to the color output characteristics of the first printing apparatus is performed. Thereby, the first printing apparatus can output an image with the second printing apparatus in a color similar to the color used when outputting an image, for example. In addition, for each color in which the evaluation data is evenly distributed in the color space, a combination of color element signal values for outputting each color is held, so that the user can save correction information for many colors in the color space without any effort. By using this, it is possible to approximate the color output characteristics of the first printing apparatus.
Further, using the above method, the correction of the second printing device is performed so that the computer storing the evaluation data, the first printing device profile, and the second printing device profile approximates the color output characteristics of the first printing device. Information may be calculated and actually applied to the second printing apparatus profile.

  The processing of the color output characteristic correction information calculation apparatus 1 has been described above. However, instead of calculating correction information that approximates the color output characteristic of one printing apparatus to the color output characteristic of the other printing apparatus, for example, a monitor Correction information for performing approximate correction between image output devices such as projectors and projectors may be calculated. At this time, RGB signal values are used as color element signal values instead of CMYK.

In this embodiment, a spline curve having a single control point at the median is used as correction information. However, correction information and mathematical expressions described in the form of a spline curve having a plurality of control points or a lookup table are used. Other correction information such as correction information represented by the following may be used.
Further, the color output characteristic difference information may be calculated by a color difference calculation formula using CIELab, or other color difference calculation formulas such as CMC, CIE94, and CIEDE2000 may be used. Further, the actual measurement value of the color output by the color output device may be a density value, for example, instead of a colorimetric value such as Lab.
The color output characteristic correction information calculation apparatus 1 according to the present embodiment may output the correction information as a text file, output only the control points in the correction information curve, or output the mathematical formula and its parameters. As long as the correction information can be specified, it may be output in any format.

  The color output characteristic correction information calculation apparatus described above has a computer system inside. The process described above is stored in a computer-readable recording medium in the form of a program, and the above process is performed by the computer reading and executing this program. Here, the computer-readable recording medium means a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like. Alternatively, the computer program may be distributed to the computer via a communication line, and the computer that has received the distribution may execute the program.

  The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

It is a block diagram which shows the structure of a color output characteristic correction information calculation apparatus. It is a figure which shows the data for evaluation. It is a figure which shows the spline curve of correction information. FIG. 4 is a diagram illustrating an outline of data of a first printing device profile or a second printing device profile. It is a figure which shows the processing flow of a color output characteristic correction information calculation apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Color output characteristic correction information calculation apparatus, 11 ... Evaluation data storage part, 12 ... Evaluation data conversion process part, 13 ... 1st profile storage part, 14 ... 2nd profile Storage unit, 15 ... first colorimetric value calculation unit, 16 ... second colorimetric value calculation unit, 17 ... correction information determination unit

Claims (6)

The color output characteristic of the second color output device that performs color output for one color based on a combination of a plurality of color element signal values is based on the combination of the color element signal values as in the second color output device. Correction information indicating the correspondence between the color output characteristics before conversion and the color output characteristics after conversion in the approximate correction is used to approximate correction to the color output characteristics of the first color output device that performs color output of the color. A color output characteristic correction information calculation device comprising:
A first color output device profile for storing a first color output device profile in which a combination of color element signal values and an actual measurement value of a color output by the first color output device according to the combination of the color element signal values are associated with each other Storage means;
A second color output device profile that stores a second color output device profile in which a combination of color element signal values and an actual measurement value of a color output by the second color output device according to the combination of the color element signal values are associated with each other Storage means;
Each color when the first color output device outputs a color using the first evaluation data based on the first evaluation data holding a plurality of combinations of color element signal values and the first color output device profile. First measured value calculation means for calculating the measured value of
The second evaluation data, respectively combinations of color component signal values converted on the basis of the correction information held by the first evaluation data, and color output characteristic of the converted color output characteristic of the pre-conversion in the approximate correction Second evaluation data calculating means for calculating a plurality of correction information with a plurality of correction information different from each other ,
Based on the second evaluation data and the second color output device profile, a second actual measurement value for calculating an actual measurement value of each color when the second color output device performs color output by the second evaluation data. A calculation means;
Based on the relationship between the actual measurement value of each color calculated by the first actual measurement value calculation means and the actual measurement value of each color calculated by the second actual measurement value calculation means, output using the first evaluation data Color output characteristic difference information indicating a difference in color output characteristics between the first color output device that performs output and the second color output device that performs output using the second evaluation data is calculated by an optimization method. The correction information for calculating the second evaluation data when the color output characteristic difference information with the smallest value is calculated, the color output characteristic of the second color output device, and the color output characteristic of the first color output device. Correction information for approximate correction and correction information determination means for determining,
A color output characteristic correction information calculation apparatus comprising: Profile reading means for reading either or both of the first color output device profile and the second color output device profile;
Profile generation means for generating one or both of the first color output device profile and the second color output device profile;
The color output characteristic correction information calculation apparatus according to claim 1, comprising either or both of: A color conversion device that approximately corrects the color output characteristics of one color output device to the color output characteristics of the other color output device,
A first color output device profile that stores a first color output device profile in which a combination of color element signal values and an actual measurement value of a color output by the other color output device according to the combination of the color element signal values are associated with each other Storage means;
A second color output device profile that stores a second color output device profile in which a combination of color element signal values and an actual measurement value of a color output from the one color output device according to the combination of the color element signal values are associated with each other Storage means;
Each color when the other color output device outputs a color using the first evaluation data based on the first evaluation data holding a plurality of combinations of color element signal values and the other color output device profile First measured value calculation means for calculating the measured value of
Each combination of color element signal values held in the first evaluation data is converted based on correction information indicating a correspondence relationship between the color output characteristics before conversion and the color output characteristics after conversion in the approximate correction. Second evaluation data calculation means for calculating a plurality of pieces of data based on a plurality of pieces of correction information having different correspondence relationships between color output characteristics before conversion and color output characteristics after conversion in the approximate correction ;
Based on the second evaluation data and the one output device profile, a second actual value calculation for calculating an actual measurement value of each color when the one color output device performs color output by the second evaluation data. Means,
Based on the relationship between the actual measurement value of each color calculated by the first actual measurement value calculation means and the actual measurement value of each color calculated by the second actual measurement value calculation means, output using the first evaluation data Calculating and optimizing color output characteristic difference information indicating a difference in color output characteristics between the other color output device that performs the output and the one color output device that performs the output using the second evaluation data The correction information for calculating the second evaluation data when the color output characteristic difference information having the smallest value is calculated by the method, the color output characteristic of the one color output device, and the color of the other color output device. Correction information for approximate correction to output characteristics and correction information determination means for determining;
Correction information applying means for applying the specified correction information to a color element signal value of a color output from the one color output device;
A color conversion device comprising: The color output characteristic of the second color output device that performs color output for one color based on a combination of a plurality of color element signal values is based on the combination of the color element signal values as in the second color output device. Correction information indicating the correspondence between the color output characteristics before conversion and the color output characteristics after conversion in the approximate correction is used to approximate correction to the color output characteristics of the first color output device that performs color output of the color. A color output characteristic correction information calculation method for a color output characteristic correction information calculation apparatus, comprising:
The first color output device profile storage means associates a combination of color element signal values with an actual color value output by the first color output device according to the combination of the color element signal values. Remember the profile,
A second color output device in which the second color output device profile storage means associates a combination of color element signal values with an actual color value output by the second color output device based on the combination of the color element signal values. Remember the profile,
Based on the first evaluation data holding a plurality of combinations of color element signal values and the first color output device profile, the first actual value calculation means calculates the first color output by the first evaluation data. Calculate the actual value of each color when the device outputs color,
A second evaluation data calculating means, said second evaluation data converted on the basis of the correction information of each combination of color component signal values held by the first evaluation data, before conversion of a color output at the approximate correction A plurality of correction information having different correspondences between the characteristics and the color output characteristics after conversion are calculated,
Based on the second evaluation data and the second color output device profile, the second actual measurement value calculation means measures the respective colors when the second color output device outputs a color using the second evaluation data. Calculate the value,
The correction information determination unit is configured to perform the first evaluation based on the relationship between the actual measurement value of each color calculated by the first actual measurement value calculation unit and the actual measurement value of each color calculated by the second actual measurement value calculation unit. Calculating color output characteristic difference information indicating a difference in color output characteristics between the first color output device that performs output using the data for use and the second color output device that performs output using the second evaluation data The correction information for calculating the second evaluation data when the color output characteristic difference information having the smallest value is calculated by the optimization method is used as the color output characteristic of the second color output device. A method for calculating color output characteristic correction information, characterized in that the correction information is determined to approximate correction to the color output characteristic of an output device. Reading one or both of the first color output device profile and the second color output device profile;
Generating one or both of the first color output device profile and the second color output device profile;
5. The color output characteristic correction information calculation method according to claim 4, further comprising: A color conversion method of a color conversion device for approximating the color output characteristics of one color output device to the color output characteristics of the other color output device,
The first color output device profile storage means associates a combination of color element signal values with an actual measured value of a color output from the other color output device according to the combination of the color element signal values. Remember the profile,
A second color output device in which the second color output device profile storage means associates a combination of color element signal values with an actual color value output from the one color output device according to the combination of the color element signal values. Remember the profile,
Based on the first evaluation data in which a plurality of combinations of color element signal values are held and the other color output device profile, the first actual value calculation means calculates the other color output by the first evaluation data. Calculate the actual value of each color when the device outputs color,
Correction information indicating a correspondence relationship between color output characteristics before conversion and color output characteristics after conversion in approximate correction for each combination of color element signal values held by the first evaluation data A plurality of pieces of second evaluation data converted based on a plurality of pieces of correction information having different correspondence relationships between color output characteristics before conversion and color output characteristics after conversion in the approximate correction ,
Based on the second evaluation data and the one output device profile, the second actual measurement value calculation means measures the actual value of each color when the one color output device outputs a color using the second evaluation data. To calculate
The correction information determination unit is configured to perform the first evaluation based on the relationship between the actual measurement value of each color calculated by the first actual measurement value calculation unit and the actual measurement value of each color calculated by the second actual measurement value calculation unit. Output characteristic difference information indicating a difference in color output characteristics between the other color output device that performs output using the data for use and the one color output device that performs output using the second evaluation data The correction information for calculating the second evaluation data when the color output characteristic difference information having the smallest value is calculated by the optimization method, the color output characteristic of the one color output device as the other Determined as correction information to be approximated to the color output characteristics of the color output device,
A color conversion method, wherein the correction information application means applies the specified correction information to a color element signal value of a color output from the one color output device.

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