JP2008060637A - Apparatus, method and program of generating color correction profile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus, a method and a program of generating a color correction profile enabling a user to easily know an accuracy result of color correction by a color correction profile. <P>SOLUTION: The apparatus of generating a color correction profile is provided with an acquiring means for acquiring target colorimetric values obtained by applying colorimetry of a colorimetric machine, to each of printing colors of a target color chart printed by a target printer on the basis of color chart data; a generating means for comparing a reference colorimetric value with each of the target colorimetric values, and generating a color correction profile for correctiong the printed colors of the target printer on the basis of results of comparison; a calculating means for comparing corrected colorimetric values obtained by colorimetry of the colorimetric machine to each of the printed colors of the correction color chart printed, on the basis of color chart data by applying the color correction profile by the target printer with the reference colormetric value, and calculating the accuracy of color correction by the color correction profile from results of comparison; and an output means for outputting the accuracy of color correction by the color correction profile. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a color correction profile generation apparatus, a color correction profile generation method, and a color correction profile generation program.

  Conventionally, it is known that a color reproducibility of a printing apparatus such as a printer is deteriorated due to a change in aged characteristics. Further, it is known that the color reproducibility of a printing apparatus varies depending on individual differences even in a state where there is no change in aging characteristics. For example, it is assumed that there are a reference printer in which color reproducibility has not deteriorated and a target printer in which color reproducibility has deteriorated. In this case, the standard colorimetric value obtained by measuring the color chart data with the standard printer using the colorimeter and the target color chart obtained by printing the same color chart data with the target printer were measured using the colorimeter. The color reproducibility of the target printer can be corrected by comparing the target colorimetric value and generating a color correction profile for correcting the print color of the target printer based on the comparison result (see, for example, Patent Document 1). .)

  By the way, in general, when a color correction profile is generated, the user checks how accurately the color can be corrected by using the generated color correction profile. In other words, the user confirms the correction accuracy of the color correction profile. To check the correction accuracy, apply the color correction profile to the color chart data described above, reprint the target color chart with the target printer, measure the color of the reprinted target color chart with the colorimeter, and measure the color. This is done by comparing the color value with a reference colorimetric value.

JP 2003-291327 A

  However, according to the confirmation method described above, accurate color correction accuracy is not required, and even if the accuracy of approximate color correction is confirmed, the colorimetric values measured for each color are obtained and the reference measurement is performed. There is a problem in that it takes time and time to confirm the accuracy of color correction because it requires a numerical calculation process such as calculating a difference from each color value and obtaining an average of these differences.

In order to solve the above-described problems, the color correction profile generation device of the present invention performs colorimetry on the color chart data and each print color of the reference color chart printed by the reference printing device serving as a reference based on the color chart data. Storage means for storing the reference colorimetric values measured by the color measuring machine, and target measurement by measuring each print color of the target color chart printed by the target printing device based on the color chart data by the color measuring machine. An acquisition means for acquiring a color value from the colorimeter, the reference colorimetric value and the target colorimetric value are compared in the same color space, and the print color of the target printing device is determined based on the comparison result. Generating means for generating a color correction profile for correction, and a correction color chart printed by the target printing apparatus based on the color chart data by applying the color correction profile; The colorimetric values measured by the colorimeter and the reference colorimetric values are compared with each other in the color space, and the accuracy of color correction using the color correction profile is calculated from the result of the previous comparison. It is characterized by comprising a calculation means and an output means for outputting the accuracy of color correction by the color correction profile.
According to the present invention, the accuracy of the color correction is calculated and output by comparing the corrected colorimetric value printed by applying the generated color correction profile and the reference colorimetric value. The user can easily and quickly know the correction accuracy of the generated color correction profile from the output result without the user himself / herself obtaining and measuring the colorimetric value.

The color correction profile generation device of the present invention outputs an estimation unit that estimates a correction accuracy of the color correction profile based on a result of comparing the reference colorimetric value and the target colorimetric value, and the estimated correction accuracy. It is preferable to further comprise a second output means.
According to the present invention, since the correction accuracy is estimated and output, the user can know the correction accuracy of the generated color correction profile without reprinting the target color chart.

In the color correction profile generation device of the present invention, each pixel value constituting the color chart data is printed with only one of the color materials of the reference printing device and the target printing device. It is preferable to represent the color.
According to the present invention, when a color correction profile is generated using a color (single color) printed with only one color material, the data amount of the color correction profile can be reduced as compared with a case where the color correction profile is generated. The time required for generation can be shortened.

In the color correction profile generation device of the present invention, it is preferable that the same color space is a CIE L * a * b * color space.
According to the present invention, since the CIE L * a * b * color space is a uniform color space, the difference between two colors perceived by humans (color difference) can be expressed by the distance between the two colors.

In the color correction profile generation device of the present invention, it is preferable that the output means displays on the display means the accuracy of color correction based on the color correction profile.
According to the present invention, the accuracy of the color correction by the color correction profile is displayed on the display means, so that the user can easily know the accuracy of the color correction by the color correction profile.

In the color correction profile generation device of the present invention, it is preferable that the display unit displays the accuracy of color correction by the color correction profile in association with at least one of green, yellow, and red colors.
According to the present invention, by displaying the color correction accuracy based on the color correction profile in association with the color, the user can visually recognize the color correction accuracy by color.

  In the color correction profile generation device of the present invention, the display unit arranges the regions representing the respective colors in series, and the accuracy of color correction by the color correction profile is set to any position of the arranged regions. You may display correspondingly.

In the color correction profile generation device of the present invention, among the regions representing the respective colors, the region associated with excellent color correction accuracy according to the color correction profile is wider than other regions. Is preferred.
According to the present invention, a plurality of color correction profiles having excellent color correction accuracy can be compared in detail.

In order to solve the above-described problems, the color correction profile generation method of the present invention measures color chart data and each print color of the reference color chart printed by the reference printing apparatus serving as a reference based on the color chart data. A storage step for storing a reference colorimetric value measured by a color measuring machine, and a target color measurement for measuring each print color of a target color chart printed by a target target printing device based on the color chart data with a colorimeter. The acquisition step of acquiring a color value from the colorimeter, the reference colorimetric value and the target colorimetric value are compared in the same color space, and the print color of the target printing device is determined based on the comparison result. A generation step of generating a color correction profile for correction, and a correction color chart printed based on the color chart data by applying the color correction profile by the target printing apparatus The colorimetric values measured by the colorimeter and the reference colorimetric values are compared with each other in the color space, and the accuracy of color correction using the color correction profile is calculated from the result of the previous comparison. And a calculation step and an output step of outputting the accuracy of color correction by the color correction profile.
According to the present invention, the accuracy of the color correction is calculated and output by comparing the corrected colorimetric value printed by applying the generated color correction profile and the reference colorimetric value. The user can easily and quickly know the correction accuracy of the generated color correction profile from the output result without the user himself / herself obtaining and measuring the colorimetric value.

In order to solve the above-described problem, the color correction profile generation program according to the present invention measures color chart data and each print color of the reference color chart printed by the reference printing apparatus serving as a reference based on the color chart data. A storage function for storing a reference colorimetric value measured by a color measuring machine, and a target color measurement by measuring a color of each print color of a target color chart printed by the target target printing device based on the color chart data. The acquisition function for acquiring a color value from the colorimeter, the reference colorimetric value and the target colorimetric value are compared in the same color space, and the print color of the target printing device is determined based on the comparison result. A generation function for generating a color correction profile for correction, and a correction color printed based on the color chart data by applying the color correction profile by the target printing device Compare the measured color values of each print color of the print with the colorimeter with the reference colorimetric values in the color space, and calculate the accuracy of color correction using the color correction profile from the results of the previous comparison. And a calculation function for outputting and an output function for outputting the accuracy of color correction based on the color correction profile.
According to the present invention, the accuracy of the color correction is calculated and output by comparing the corrected colorimetric value printed by applying the generated color correction profile and the reference colorimetric value. The user can easily and quickly know the correction accuracy of the generated color correction profile from the output result without the user himself / herself obtaining and measuring the colorimetric value.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment)

  FIG. 2 shows a personal computer (PC) 10 as a color correction profile generation apparatus according to an embodiment of the present invention, a target printer 11 as a target printing apparatus, and a target color chart printed by the target printer 11 based on color chart data. 4 is a schematic diagram showing a colorimeter 12 that measures color 47, a reference printer 13 as a reference printing device, and a colorimeter 14 that measures the reference color chart 46 printed by the reference printer 13 based on color chart data. . The target printer 11 and the reference printer 13 are the same model, and the reference printer 13 and the target printer 11 use four color inks of C (cyan), M (magenta), Y (yellow), and K (black) as color materials. I have. In addition, the kind of ink is not restricted to this, You may provide the ink of 6 colors or 7 colors.

  FIG. 3 is a block diagram illustrating a hardware configuration of the PC 10. The PC 10 includes a CPU 21, a ROM 22, a RAM 23, a display controller 24, an interface unit 25, a removable memory controller (RMC) 26, an external storage unit 27, and an operation unit 28, which are connected to each other via a bus 30.

  The CPU 21 controls the entire PC 10 by executing programs stored in the ROM 22 and the external storage unit 27. Further, the CPU 21 causes the PC 10 to function as a storage unit, an acquisition unit, a generation unit, a calculation unit, and an output unit by executing a color correction profile generation program. The ROM 22 is a memory that stores various programs and data in advance, and the RAM 23 is a memory that temporarily stores various programs and data. These various programs and data may be downloaded and input from a predetermined server via a communication network, or may be read from a removable memory and input.

  The display controller 24 as output means is controlled by the CPU 21 to display various information on a display 31 such as a CRT (Cathode Ray Tube), LCD (Liquid Crystal Display), and FPD (Flat Panel Display) as display devices.

  The interface unit 25 as an acquisition unit includes a USB controller, a USB connector, and the like for communicating with an external system such as the colorimeter 12 such as a spectrophotometer and the target printer 11. The communication standard is not limited to USB, but may be any standard such as IEEE 1394, infrared, Ethernet (registered trademark).

  The RMC 26 as an acquisition unit is connected to a removable memory via a connector (not shown), and controls data transfer between the removable memory and the RAM 23. The removable memory may be a card-type flash memory (so-called memory card), or any other non-volatile storage medium that can be repeatedly written.

  The external storage unit 27 as a storage unit includes a hard disk, a hard disk controller, and the like, and performs colorimetry on the operating system (OS), the color correction profile generation program, and the reference color chart 46 printed by the reference printer 13 based on the color chart data. The standard colorimetric values measured by the machine 14, the same color chart data as the color chart data used by the standard printer 13 for printing the standard color chart 46, and the digital image represented in the sRGB color space are separated into the CMYK color space. A three-dimensional look-up table (3DLUT) and other various programs and data are stored. The reference colorimetric value is generated by, for example, the manufacturer of the reference printer 13, and the generated reference colorimetric value may be distributed attached to the target printer 11, or may be distributed to the PC 10 by downloading via a communication network. good.

  The operation unit 28 includes a keyboard controller to which a keyboard 29 is connected, a mouse controller to which a mouse (not shown) is connected, and the like.

  Each function provided in the present invention is realized by a hardware resource whose function is specified by the configuration itself, a hardware resource whose function is specified by a program, or a combination thereof. Further, each of these functions is not limited to those realized by hardware resources that are physically independent of each other.

  Next, color chart data will be described. FIG. 4 is a schematic diagram showing a color chart printed based on the color chart data. The color chart is an image representing a plurality of colors, and a plurality of frames 41 in the figure are each filled with only one ink of CMYK. In the frame 41, pixel values (C, M, Y, K) used for printing the color (print color) printed in the frame are shown. For example, the plurality of print colors included in the C column shown in FIG. 4 are colors printed using only C ink, and the pixel values used for printing the color printed in the C column are C components. Are set to change at 10 intervals such as 10, 20,... As shown in the figure, the C column pixel values are set to 0 for the gradation values of the M component, Y component, and K component. The same applies to the M, Y, and K columns.

  Next, correction of color reproducibility will be described. FIG. 5A is a schematic diagram showing printing by the reference printer 13, FIG. 5B is a schematic diagram showing printing before correction by the target printer 11, and FIG. 5C is correction by the target printer 11. It is a schematic diagram which shows subsequent printing. In the illustrated color chart data 45, (10, 0, 0, 0) is set as the pixel value of the color printed in the nth area of the color chart, and the color of the color printed in the mth area of the color chart. (20, 0, 0, 0) is set as the pixel value, and (30, 0, 0, 0) is set as the pixel value of the color printed in the p-th area. When the color chart data 45 is printed by the reference printer 13 as shown in FIG. 5A, dark cyan is printed in the nth area of the reference color chart 46, and medium density cyan is printed in the mth area. Suppose that light cyan is printed in the p-th region.

  As shown in FIG. 5B, when the color chart data 45 is printed by the target printer 11, color misregistration occurs due to deterioration of color reproducibility due to a change in characteristics over time, and the above-described n-th region of the target color chart 47 is described above. Assume that another color different from the color is printed, dark cyan is printed in the mth area, medium density cyan is printed in the pth area, and light cyan is printed in another area (not shown). In the case of a color shift as shown in FIG. 5B, in order to correct the color shift, for example, in the case of the nth area, the color printed in the nth area when printing with the target printer 11 The pixel value of (10, 0, 0, 0) may be replaced with (20, 0, 0, 0). As shown in FIG. 5C, if (10, 0, 0, 0) is replaced with (20, 0, 0, 0) and printing is performed, the target color chart 48 printed by the target printer 11 is also in the nth position. Dark cyan is printed in the area.

  That is, not only the color chart data 45 but also a digital image expressed in the CMYK color space is printed by the target printer 11 as long as the digital image includes a pixel value of (10, 0, 0, 0). By replacing it all with (20, 0, 0, 0), it is possible to print dark cyan with no color misregistration. Similarly, if a pixel value of (20, 0, 0, 0) is included, by replacing it all with (30, 0, 0, 0), printing with no color misregistration can be performed for medium density cyan. . For light cyan, the area where it is printed is found, and the pixel value (30, 0, 0, 0) contained in the digital image is the pixel value (Cx, Mx) of the color printed in the found area. , Yx, Kx), light cyan can be printed without color misregistration. The same applies to all other colors.

  As described above, in order to correct the color reproducibility, each pixel value of the color chart data is replaced by comparing the reference color chart 46 printed by the reference printer 13 with the target color chart 47 printed by the target printer 11. When a pixel value to be specified is specified and a digital image is printed by the target printer 11, each pixel value constituting the digital image may be replaced in accordance with the association.

  In the comparison described above, specifically, the reference colorimetric value obtained by measuring the reference color chart 46 with the colorimeter 14 and the target colorimetric value obtained by measuring the object color chart 47 with the colorimeter 12 are the same color space. Do by comparing in. In this embodiment, the colorimeter 12 and the colorimeter 14 output colorimetric values (L, a, b) expressed in the CIE L * a * b * color space. For example, the color values (L1, a1, b1) of print colors obtained by printing the pixel values (10, 0, 0, 0) with the reference printer 13 and the pixel values (20, 0, 0, 0) with the target printer 11 are obtained. Assume that the measured color values (L2, a2, b2) of the printed colors match. In this case, the pixel value (10, 0, 0, 0) is printed by the reference printer 13 by associating the pixel value (10, 0, 0, 0) with the pixel value (20, 0, 0, 0). The target printer 11 can print the same print color as the print color.

  However, it is rare that a matching colorimetric value is found, and it can be said that there is almost no colorimetric value. Therefore, in the present embodiment, for each print color of the reference color chart 46, printing of the print color having the smallest color difference from the print color of the target color chart 47 as the pixel value used for printing the print color. The pixel values used in are associated with each other. Here, the color difference is the distance between two colors in the L * a * b * color space. In the L * a * b * color space, which is a uniform color space, the difference between the two colors perceived by a person is represented by the distance. be able to. The color difference ΔE (CIE ΔE1994) can be obtained by the following equation (1).

  However, if the pixel values used for printing the printing color with the smallest color difference are associated with each other, the color deviation corresponding to the color difference remains, although it is small, the correction accuracy is lowered. Here, the correction accuracy refers to a colorimetric value obtained by measuring the print color and a reference color for each print color of the target color chart that is reprinted by the target printer 11 by replacing the pixel values of the color chart data 45 according to the correspondence. In the chart, it means a value obtained by averaging color differences from a reference colorimetric value obtained by measuring a print color printed in the same area as the print color. When the correction accuracy is defined as described above, the correction accuracy is approximately proportional to a value obtained by averaging the “smallest color difference” obtained for each color in the association described above. That is, the correction accuracy may be estimated by using the color difference obtained at the time of association.

Next, processing for generating a color correction table will be described. The color correction table is a table for associating different pixel values as described above, and is generated in advance as a color correction table in this embodiment. FIG. 6 is a flowchart showing a flow of processing for generating a color correction table.
In S105, the CPU 21 prints the target color chart by the target printer 11 based on the color chart data.
In S110, the CPU 21 inputs a target colorimetric value obtained by measuring the target color chart with the colorimeter 12. Specifically, the user measures the printed target color chart with the colorimeter 12, and the CPU 21 acquires the target colorimetric value from the colorimeter 12 via a removable memory or a communication cable.

In S115, the CPU 21 sets a colorimetric value table that associates the color chart data stored in the HDD, the target colorimetric value input in S110, and the reference colorimetric value stored in the HDD with respect to each CMYK component. Generate. An example of a C component colorimetric value table is shown below.
FIG. 7 is a schematic diagram illustrating an example of a C component colorimetric value table. The first column of the color measurement value table stores the pixel values of column C shown in FIG. 4, and the second column measures the print color printed by the reference printer 13 using the pixel values of the first column. A reference colorimetric value measured by the color machine 14 is stored.
The third column stores the target colorimetric values obtained by measuring the print colors printed by the target printer 11 using the pixel values in the first column by the colorimeter 12.

  In S120, the CPU 21 generates a color correction table for each component based on each colorimetric value table. Specifically, the CPU 21 selects one row from the color measurement value table, and calculates the reference color measurement value stored in the second column of the selected row and all the target color measurement values stored in the third column. Find the color difference. Next, the CPU 21 stores the gradation value of the component corresponding to the colorimetric value table of the pixel value stored in the first column of the selected row and the row in which the target colorimetric value having the smallest color difference is stored. The gradation values of the components corresponding to the colorimetric value table of the pixel values stored in the first column are associated with each other and stored in the color correction table shown in FIG. More specifically, the C component is stored in the second column of the second row among the target colorimetric values stored in the third column in the case of the second row of the colorimetric value table shown in FIG. It is assumed that the target colorimetric value having the smallest color difference from the reference colorimetric value is the target colorimetric value in the fourth row. In this case, the gradation value of the C component of the pixel value stored in the first column of the second row is associated with the gradation value of the C component of the pixel value stored in the first column of the fourth row. And stored in the color correction table as shown in FIG. The color correction table corresponds to a “color correction profile” recited in the claims.

In the process of generating the color correction table, the CPU 21 stores the “smallest color difference” obtained for each row of each colorimetric value table in the RAM 23 as shown in FIG.
In S125, the CPU 21 estimates the color reproducibility correction accuracy. Specifically, for example, the CPU 21 estimates the correction accuracy by obtaining an average value of all the color differences. Note that the CPU 21 may obtain an average value of color differences for each color component.

  In S130, the CPU 21 outputs the estimated correction accuracy. Specifically, for example, as shown in FIG. 9, the CPU 21 displays a correction accuracy prediction screen 50 having a scale representing low to high on the display 31, and displays a pointer 51 at a position corresponding to the average value of color differences. The right end of the scale indicates that the average value of the color difference is 0, and the average value of the color difference increases toward the left end. The red, yellow and blue of the scale correspond to the color of the traffic light, and the user can know the approximate correction accuracy by showing the pointer 51 at a position corresponding to the average value of the color difference. The average value of the color difference may be an average value for each component, and in that case, the correction accuracy prediction screen 50 shown in FIG. 9 may be displayed for each component.

  Next, color correction using the color correction table will be described. FIG. 10 is a flowchart showing the flow of color correction using the color correction table. In S205, the CPU 21 separates the digital image to be printed expressed in the sRGB color space into the CMYK color space with reference to the three-dimensional lookup table (3DLUT).

  In S210, the color of the digital image separated into the CMYK color space is corrected based on the color correction table. Specifically, for each pixel value constituting the digital image, the CPU 21 replaces the gradation value of each CMYK component constituting the pixel value with reference to the corresponding color correction table. For example, if the gradation value of the C component is “10”, the C component color correction table is referred to and replaced with “20”. However, in the color chart data, since the gradation values are selected at 10 intervals, the gradation value corresponding to each gradation value may not exist in the color correction table. In that case, the color correction table may be appropriately interpolated by linear interpolation, curve interpolation, or the like to obtain the replacement destination gradation value. Next, in S215, the CPU 21 causes the target printer 11 to print the target color chart based on the correction in S210.

  In S220, the CPU 21 measures the printed target color chart with the colorimeter 12, and acquires the target color value. Specifically, the user measures the color of the printed target color chart with the colorimeter 12.

  In S225, the CPU 21 calculates the accuracy of color correction by the color correction table from the target colorimetric value and the reference colorimetric value. Specifically, the calculation means that the CPU 21 functions is based on the colorimetric value obtained by measuring the print color and the reference color chart for each print color of the target color chart actually reprinted by the target printer 11 according to the color correction table. A value obtained by averaging the color differences from the reference colorimetric value obtained by measuring the print color printed in the same area as the print color is calculated as the color correction accuracy by the color correction table. That is, as in the process of generating the color correction table, the “smallest color difference” is obtained for each row of each colorimetric value table, stored in the RAM 23, and the average value of the color differences stored in the RAM 23 is calculated. Thus, the accuracy of color correction is calculated.

  In S230, the CPU 21 outputs the calculated accuracy of color correction. Specifically, as shown in FIG. 1, a color correction accuracy screen 60 having areas representing “excellent” to “caution” to “bad” is displayed on the display 31 and is positioned at a position corresponding to the average value of color differences. A pointer 61 is displayed. The right end of the scale indicates that the average value of the color difference is 0, and the average value of the color difference increases toward the left end. The inside of the area is divided by a reference value for quality determination regarding the average value of color differences set in advance, and each inside is filled with red, yellow and blue. These colors are associated with the accuracy of color correction according to the color correction table and also correspond to the color of the traffic light. Therefore, by indicating the pointer 61 at a position corresponding to the average value of the color difference, the user can You can visually know the accuracy of approximate color correction. Note that the colors to be filled are not limited to the three colors of red, yellow, and blue, and other colors may be further added. In addition, in the blue area where the color correction accuracy based on the color correction table indicates “excellent”, this blue area is compared with the red area and the yellow area in order to display the average value of color differences in detail. May be displayed. Further, when the calculated average value of the color difference indicates “attention” (yellow region) and “bad” (red region) as the accuracy of color correction, the pointer 61 is displayed in order to inform the user more visually. The approximate center portion of each area may be indicated without depending on the average value. The correction accuracy prediction screen 50 and the color correction accuracy screen 60 may be in the same mode.

  According to the color correction profile generation device according to the embodiment of the present invention described above, since the accuracy of color correction by the color correction table is indicated by color on the display 31, the user can perform color correction of the generated color correction profile. Can see the level of accuracy.

  In the present embodiment, the case where a color correction profile is generated using only a single color printed with one ink has been described as an example. However, a color correction profile may be generated using mixed colors. If a color correction profile is generated using a single color, a single color can be printed more correctly, so that mixed colors can also be corrected more correctly. However, when a color correction profile is generated using only a single color, the correction accuracy for the mixed color is inferior compared to the case where the color correction profile is generated using a mixed color. If it is desired to further improve the correction accuracy for color mixing, a color correction profile may be generated using color mixing. However, when color mixing is used, the data amount of the color correction profile increases and more time is required to generate the color correction profile. On the other hand, if a color correction profile is generated using only a single color, the data amount of the color correction profile can be reduced and the color correction profile can be generated in a short time.

  In addition, this invention is not limited to the said embodiment, In the range which does not deviate from the summary, it is applicable to various embodiment.

The schematic diagram of the screen which shows the precision of the color correction which concerns on embodiment of this invention. 1 is a schematic diagram of a color correction profile generation apparatus according to an embodiment of the present invention. 1 is a block diagram of a color correction profile generation apparatus according to an embodiment of the present invention. The schematic diagram which shows the color chart which concerns on embodiment of this invention. FIG. 4 is a schematic diagram for explaining correction of color reproducibility according to an embodiment of the present invention. The flowchart which concerns on embodiment of this invention. The schematic diagram which shows the table which concerns on embodiment of this invention. FIG. 3 is a schematic diagram showing a color correction profile according to an embodiment of the present invention. The schematic diagram of the screen which shows the correction | amendment precision prediction which concerns on embodiment of this invention. The flowchart which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Personal computer (color correction profile generation apparatus), 11 ... Target printer (target printing apparatus), 12 ... Colorimeter, 13 ... Standard printer (reference printing apparatus), 14 ... Colorimeter, 21 ... CPU (storage means) Acquisition means, generation means, estimation means, output means), 22 ... ROM
DESCRIPTION OF SYMBOLS 23 ... RAM, 24 ... Display controller (output means), 25 ... Interface part (acquisition means), 26 ... Removable memory controller (acquisition means), 27 ... External storage part (storage means), 28 ... Operation part, 29 ... Keyboard , 30 ... bus, 31 ... display (display device), 45 ... color chart data, 46 ... reference color chart, 47 ... target color chart, 50 ... correction accuracy prediction screen, 51 ... pointer, 60 ... color correction accuracy screen, 61 ... Guidelines.

Claims (10)

Storage means for storing color chart data and reference colorimetric values obtained by measuring each print color of the reference color chart printed by the reference printing apparatus serving as a reference based on the color chart data with a colorimeter;
An acquisition unit for acquiring, from the colorimeter, a target colorimetric value obtained by measuring a color of each print color of the target color chart printed by the target target printing device based on the color chart data with a colorimeter;
Generating means for comparing the reference colorimetric value and the target colorimetric value in the same color space and generating a color correction profile for correcting the print color of the target printing device based on the comparison result;
The target printing device applies the color correction profile, and the correction colorimetric value obtained by measuring each print color of the correction color chart printed based on the color chart data by the colorimeter, the reference colorimetric value, Calculating means for calculating the accuracy of color correction according to the color correction profile from the result of the previous comparison,
Output means for outputting the accuracy of color correction by the color correction profile;
A color correction profile generation apparatus comprising: The color correction profile generation device according to claim 1,
An estimation means for estimating the correction accuracy of the color correction profile based on a result of comparing the reference colorimetric value and the target colorimetric value;
A color correction profile generation apparatus, further comprising: a second output unit that outputs the estimated correction accuracy. The color correction profile generation device according to claim 1,
Each pixel value constituting the color chart data represents a color that is printed with only one of a plurality of color materials included in the reference printing device and the target printing device, respectively. Correction profile generation device. The color correction profile generation device according to any one of claims 1 to 3,
The color correction profile generation apparatus according to claim 1, wherein the same color space is a CIE L * a * b * color space. The color correction profile generation device according to any one of claims 1 to 4,
The output means causes the display means to display the accuracy of color correction based on the color correction profile. The color correction profile generation device according to claim 5,
The display means displays the color correction accuracy by the color correction profile in association with at least one of green, yellow and red colors. The color correction profile generation device according to claim 6,
The display means arranges areas representing the respective colors in series, and displays the accuracy of color correction according to the color correction profile in association with any position of the arranged areas. Color correction profile generation device. The color correction profile generation device according to claim 7,
The color correction profile generation apparatus characterized in that, among the regions representing the respective colors, a region associated with excellent accuracy of color correction by the color correction profile is wider than other regions. A storage step of storing color chart data and a reference colorimetric value obtained by measuring each print color of the reference color chart printed by the reference printing apparatus based on the color chart data with a colorimeter;
An acquisition step of acquiring, from the colorimeter, a target colorimetric value obtained by measuring a color of each print color of the target color chart printed by the target target printing device based on the color chart data with a colorimeter;
Generating the color correction profile for comparing the reference colorimetric value and the target colorimetric value in the same color space, and correcting the print color of the target printing device based on the comparison result;
The target printing device applies the color correction profile, and the correction colorimetric value obtained by measuring each print color of the correction color chart printed based on the color chart data by the colorimeter, the reference colorimetric value, Calculating in the color space, and calculating the accuracy of color correction by the color correction profile from the result of the previous comparison,
An output step of outputting the accuracy of color correction by the color correction profile;
A color correction profile generation method comprising: A storage function for storing color chart data and a reference colorimetric value obtained by measuring each print color of the reference color chart printed by the reference printing apparatus based on the color chart data with a colorimeter;
An acquisition function for acquiring, from the colorimeter, a target colorimetric value obtained by measuring a color of each print color of the target color chart printed by the target target printing device based on the color chart data with a colorimeter;
A function of comparing the reference colorimetric value and the target colorimetric value in the same color space, and generating a color correction profile for correcting the print color of the target printing device based on the comparison result;
The target printing device applies the color correction profile, and the correction colorimetric value obtained by measuring each print color of the correction color chart printed based on the color chart data by the colorimeter, the reference colorimetric value, A calculation function for calculating the accuracy of the color correction by the color correction profile from the result of the previous comparison,
An output function for outputting the accuracy of color correction by the color correction profile;
A color correction profile generation program that causes a computer to execute the above.

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