Color adjustment system, color adjustment device, color adjustment method and program

Abstract

To make color adjustments to specified colors skill-free even when printing on paper other than white.SOLUTION: A color adjustment device causes a printing device to print a color chart including multiple color patches in which the values of respective color components in the printing device are changed for the specified color (step S5). The color adjustment device then determines a printing specified color by shifting the specified color by the amount of the background color of the paper on which the color chart is printed, and calculates the values of the color components respectively corresponding to the multiple color patches so as to represent the printing specified color and its neighboring colors (step S3). The color adjustment device selects a color patch of a color closest to the specified color from the multiple color patches included in the printed color chart (step S6). The color adjustment device performs color adjustment of the specified color printed by the printing device on the basis of the value of each color component corresponding to the selected color patch (step S10).SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a color adjustment system, a color adjustment device, a color adjustment method, and a program. [Background technology]

[0002] Special colors are used for printing corporate colors, etc. To express special colors without using special color materials (special color toner, special color ink, etc.), it is necessary to mix cyan, magenta, yellow, and black color materials to reproduce a color similar to the special color. This color adjustment requires advanced skills, so only experienced workers can do it.

[0003] Therefore, for color adjustment of designated colors such as spot colors, there is a method that repeats the steps of printing a color chart on which multiple color patches close to the sample color (designated color) are arranged, and selecting the color patch of the color closest to the sample color from the multiple printed color patches.

[0004] For example, a technique has been proposed in which, before printing a color chart, the variation range of the printed color is predicted based on the type of input method for the specified color, and the number of color patches or color spacing is determined based on the variation range (see Patent Document 1). This reduces the number of color patches to be compared with the color sample and the number of times the color chart is printed, improving the efficiency of color adjustment work. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-114717 Summary of the Invention [Problem to be solved by the invention]

[0006] However, this color adjustment method, which involves printing multiple color patches (candidate colors) and selecting the color patch that is closest to the specified color, assumes that the background color of the paper is white. In other words, if the paper on which the color chart is printed is a color other than white, it is difficult to perform color adjustment using this method.

[0007] When printing multiple color patches (candidate colors) on paper other than white, the colors of each color patch end up being far from the specified color. This makes it difficult for the operator to select the color patch in the color chart that is closest to the specified color. In such cases, the operator must repeatedly print the color chart or make additional adjustments until a color close to the specified color appears on the color chart. This requires a lot of effort and skill from the operator.

[0008] The present invention has been made in consideration of the above-mentioned problems in the prior art, and aims to make color adjustments to designated colors skillless even when printing on paper other than white. [Means for solving the problem]

[0009] In order to solve the above problem, the invention described in claim 1 is a color adjustment system comprising: a chart creation means for causing a printing device to print a color chart including a plurality of color patches in which the values ​​of each color component in the printing device are changed for a specified color; a selection means for selecting a color patch of a color closest to the specified color from the plurality of color patches included in the printed color chart; and a color adjustment means for performing color adjustment of the specified color printed by the printing device based on the values ​​of each color component corresponding to the selected color patch, wherein the chart creation means determines a specified printing color obtained by shifting the specified color by an amount corresponding to the background color of the paper on which the color chart is printed, and calculates the values ​​of each color component corresponding to each of the plurality of color patches so as to represent the specified printing color and its neighboring colors.

[0010] The invention of claim 2 relates to the color adjustment system of claim 1, further comprising a storage means for storing absolute color values ​​of the specified color and absolute color values ​​of the base color, wherein the absolute color values ​​of the specified color and the base color stored in the storage means are data obtained by measuring the specified color and the base color, respectively, or data that has been registered in advance, and the chart creation means calculates values ​​of each color component corresponding to each of the plurality of color patches based on the absolute color values ​​of the specified color and the absolute color values ​​of the base color.

[0011] In a third aspect of the present invention, in the color adjustment system of the first aspect, the chart creation means automatically determines intervals between color components in the plurality of color patches based on the designated color and the base color.

[0012] The invention described in claim 4 is the color adjustment system described in claim 1, wherein the chart creation means determines whether the designated printing color is within the color gamut of the printing device or outside the color gamut, and if it determines that the designated printing color is outside the color gamut of the printing device, converts the designated printing color to a color within the color gamut of the printing device so as to maintain lightness, maintain saturation, or minimize the color difference before and after conversion.

[0013] The invention described in claim 5 is a color adjustment system described in claim 1, in which printing of the color chart and selection of a color patch of a color closest to the specified color are repeatedly performed, and the chart creation means automatically determines the spacing of each color component in the plurality of color patches included in the color chart to be printed next, based on the color patch selected by the selection means from the plurality of color patches included in the color chart printed in the previous stage.

[0014] The invention described in claim 6 is the color adjustment system described in claim 5, further comprising a history storage means for storing a history of the color patches selected by the selection means and the color charts including the color patches, wherein the chart creation means causes the printing device to reprint a specified color chart from the color charts stored in the history storage means, and the selection means reselects a color patch of a color closest to the specified color from the plurality of color patches included in the reprinted color chart.

[0015] The invention described in claim 7 is the color adjustment system described in claim 1, further comprising a colorimeter that measures the color of the plurality of color patches included in the printed color chart, and the selection means selects the color patch that has the smallest color difference from the specified color based on the color measurement values ​​corresponding to each of the plurality of color patches obtained by the colorimeter.

[0016] The invention of claim 8 is the color adjustment system of claim 1, which includes a colorimeter that measures the plurality of color patches included in the printed color chart, and a setting means that sets, as the selection means, a first selection means that selects a color patch with the smallest color difference from the specified color based on the colorimetric values ​​corresponding to each of the plurality of color patches obtained by the colorimeter, or a second selection means that selects a color patch with a color closest to the specified color by accepting the result of an operator's visual judgment.

[0017] The invention of claim 9 is the color adjustment system of claim 1, further comprising a colorimeter that measures the color of the plurality of color patches included in the printed color chart, and a setting means that sets a first mode or a second mode, wherein in the first mode, the chart creation means automatically determines the intervals of each color component in the plurality of color patches, and when the chart creation means determines that the specified color for printing is outside the color gamut of the printing device, the chart creation means automatically converts the specified color for printing into a color within the color gamut of the printing device according to a predetermined criterion, and the selection means selects the plurality of color patches obtained by the colorimeter. and automatically selects a color patch having the smallest color difference from the specified color based on the color measurement values ​​corresponding to each of the color patches, and in the second mode, the chart creation means determines the spacing between each color component in the plurality of color patches based on manual instructions from an operator, and when the chart creation means determines that the specified color for printing is outside the color gamut of the printing device, it converts the specified color for printing to a color within the color gamut of the printing device according to a standard manually set by the operator, and the selection means selects a color patch whose color is closest to the specified color by accepting the result of visual judgment by the operator.

[0018] The invention described in claim 10 is a color adjustment device comprising: a chart creation means for causing a printing device to print a color chart including a plurality of color patches in which the values ​​of each color component in the printing device are changed for a specified color; a selection means for selecting a color patch of a color closest to the specified color from the plurality of color patches included in the printed color chart; and a color adjustment means for performing color adjustment of the specified color printed by the printing device based on the values ​​of each color component corresponding to the selected color patch, wherein the chart creation means determines a specified printing color obtained by shifting the specified color by an amount corresponding to the background color of the paper on which the color chart is printed, and calculates the values ​​of each color component corresponding to each of the plurality of color patches so as to represent the specified printing color and its neighboring colors.

[0019] The invention described in claim 11 is a color adjustment method including: a chart creation step of causing a printing device to print a color chart including a plurality of color patches in which the values ​​of each color component in the printing device are changed for a specified color; a selection step of selecting a color patch of a color closest to the specified color from the plurality of color patches included in the printed color chart; and a color adjustment step of performing color adjustment of the specified color printed by the printing device based on the values ​​of each color component corresponding to the selected color patch. In the chart creation step, a printing specified color is determined by shifting the specified color by an amount corresponding to the background color of the paper on which the color chart is printed, and the values ​​of each color component corresponding to each of the plurality of color patches are calculated so as to represent the printing specified color and its neighboring colors.

[0020] The invention described in claim 12 is a program for causing a computer to function as: a chart creation means for causing a printing device to print a color chart including a plurality of color patches in which the values ​​of each color component in the printing device are changed for a specified color; a selection means for selecting a color patch of a color closest to the specified color from the plurality of color patches included in the printed color chart; and a color adjustment means for performing color adjustment of the specified color printed by the printing device based on the values ​​of each color component corresponding to the selected color patch, wherein the chart creation means determines a specified printing color by shifting the specified color by the amount of the background color of the paper on which the color chart is printed, and calculates the values ​​of each color component corresponding to each of the plurality of color patches so as to represent the specified printing color and its neighboring colors. [Effects of the Invention]

[0021] According to the present invention, color adjustment for a specified color can be performed without requiring skill even when printing on paper other than white. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a system configuration diagram of a printing system according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a block diagram showing the functional configuration of a color adjustment device and a printing device that constitute the printing system. [Figure 3] 1 is an example of a color chart. [Figure 4A] This is an example of a sample printout. [Figure 4B] This is an example of a sample printout in which the specified color and background color are dark. [Figure 4C] This is an example of a sample printout in which the specified color and background color are light. [Figure 5] 10A and 10B are diagrams for explaining an adjustment method when a specified printing color is outside the color gamut of a printing device. [Figure 6] 10 is a flowchart showing a color adjustment process executed by the color adjustment device. [Figure 7] 10 is a flowchart showing a first candidate color calculation process. [Figure 8] 10 is an example of an adjustment screen that is displayed before printing a color chart. [Figure 9] 10 is an example of an adjustment history table. [Figure 10] 10 is an example of an adjustment screen in which color patches are automatically selected based on the color measurement results. [Figure 11] 10 is an example of an adjustment screen when a color patch is manually selected by an operator. [Figure 12] 10 is a flowchart showing a second candidate color calculation process in the second embodiment. [Figure 13] 11 is a flowchart showing a third candidate color calculation process in the third embodiment. [Figure 14] 13 is an example of a designated color list screen in the fourth embodiment. [Figure 15] 13 is an example of a base color list screen in the fourth embodiment. [Figure 16] FIG. 13 is a diagram showing setting contents for a first mode and a second mode in the fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Advantages and features provided by the embodiments will be understood from the following detailed description and drawings. However, the scope of the present invention is not limited to the embodiments disclosed below or the examples shown in the drawings.

[0024] [First embodiment] First, a first embodiment of the present invention will be described. 1 shows the system configuration of a printing system 100 as a color adjustment system in the first embodiment. The printing system 100 is used in printing companies and the like. The printing system 100 includes a color adjustment device 10, a colorimeter 20, and a printing device 30. The color adjustment device 10 and the colorimeter 20 are connected via a cable 101 so as to be able to communicate data with each other. The color adjustment device 10 and the printing device 30 are connected via a communication line 102 so as to be able to communicate data with each other.

[0025] The color adjustment device 10 is used by an operator who performs color management and printing work, etc. The color adjustment device 10 is configured by a PC (Personal Computer) or the like. The colorimeter 20 measures the color of an object and outputs colorimetric values. The colorimetric values ​​include absolute color values ​​(L * a * b * Absolute color values ​​(such as values, XYZ values, etc.) are used. Absolute color values ​​are device-independent values. The printing device 30 prints on paper. For example, the printing device 30 prints on paper based on the print data sent from the color adjustment device 10.

[0026] FIG. 2 shows the functional configuration of the color adjustment device 10 and the printing device 30 that constitute the printing system 100. The color adjustment device 10 includes a control unit 11, an operation unit 12, a display unit 13, a communication unit 14, a storage unit 15, an IF unit 16, etc. The units constituting the color adjustment device 10 are connected via a bus.

[0027] The control unit 11 includes a CPU (Central Processing Unit), RAM (Random Access Memory), etc. The control unit 11 comprehensively controls the processing operations of each unit of the color adjustment device 10. Specifically, the CPU reads out various processing programs stored in the storage unit 15, loads them into the RAM, and performs various processes in cooperation with the programs.

[0028] The operation unit 12 includes a keyboard, a mouse, etc. The operation unit 12 outputs an operation signal input by operating the keyboard or the mouse to the control unit 11. The operation unit 12 may have a touch screen configured integrally with the display unit 13. In this case, the operation unit 12 outputs an operation signal to the control unit 11 according to the position of the touch operation.

[0029] The display unit 13 includes a monitor such as an LCD (Liquid Crystal Display), etc. The display unit 13 displays various screens in accordance with instructions of a display signal input from the control unit 11.

[0030] The communication unit 14 is configured by a network interface, etc. The communication unit 14 transmits and receives data to and from an external device (such as the printing device 30) connected via a communication line 102 including a LAN (Local Area Network), a WAN (Wide Area Network), etc. The color adjustment device 10 and the printing device 30 may be connected by a dedicated cable.

[0031] The storage unit 15 is configured with an HDD (Hard Disk Drive), an SSD (Solid State Drive), a non-volatile semiconductor memory, etc. The storage unit 15 stores various processing programs, data necessary for executing the programs, etc. For example, the storage unit 15 stores a color adjustment processing program 151 and an adjustment history table 152.

[0032] The IF unit 16 is an interface for connecting to the colorimeter 20. The control unit 11 acquires colorimetric values ​​from the colorimeter 20 via the IF unit 16 and the cable 101. The color adjustment device 10 and the colorimeter 20 may be connected to each other via a communication line so that data communication is possible.

[0033] The control unit 11 causes the printing device 30 to print a color chart. In other words, the control unit 11 functions as a chart creation means. The color chart includes a plurality of color patches in which the values ​​of each color component in the printing device 30 are changed for a specified color. The specified color is a color (such as a spot color) specified by a sample printout or the like. The color components in the printing device 30 are cyan (C), magenta (M), yellow (Y), and black (K). 3 shows an example of a color chart 40. The color chart 40 includes a plurality of color patches 41.

[0034] The control unit 11 determines the designated printing color by shifting the designated color by the amount of the background color of the paper on which the color chart is printed. The control unit 11 calculates the value of each color component corresponding to each of the multiple color patches so as to represent the designated printing color and colors neighboring the designated printing color. A neighboring color is a color that is close to a specified color (here, the designated printing color). The degree of closeness of a color that is considered a neighboring color can be set arbitrarily.

[0035] The control unit 11 selects a color patch of a color closest to the specified color from among a plurality of color patches included in the printed color chart, that is, the control unit 11 functions as a selection unit.

[0036] The control unit 11 performs color adjustment of the designated color to be printed by the printing device 30 based on the values ​​of each color component corresponding to the selected color patch. That is, the control unit 11 functions as a color adjustment unit. For example, the control unit 11 stores the designated color and the values ​​of each color component corresponding to the selected color patch in association with each other.

[0037] The control unit 11 acquires data obtained by measuring the designated color using the colorimeter 20 via the IF unit 16. The control unit 11 stores the absolute color value of the designated color acquired from the colorimeter 20 in the memory unit 15 (storage means). The control unit 11 acquires data obtained by measuring the base color using the colorimeter 20 via the IF unit 16. The control unit 11 stores the absolute color value of the base color acquired from the colorimeter 20 in the memory unit 15 (storage means). The control unit 11 calculates the value of each color component corresponding to each of the plurality of color patches based on the absolute color value of the designated color and the absolute color value of the base color.

[0038] FIG. 4A shows an example of a sample print 50A. The sample print 50A is brought to a printing company or the like by a print client, for example. The sample print 50A has a specified color portion 51A and a base color portion 52A. The specified color portion 51A is the portion of the paper that is printed in the specified color. The base color portion 52A is the portion of the paper where the specified color is not printed, and where the paper itself is exposed. By measuring the designated color portion 51A and the base color portion 52A of the sample print 50A with the colorimeter 20, the control unit 11 of the color adjustment device 10 obtains color values ​​necessary for color adjustment of the designated color.

[0039] Figures 4B and 4C show examples of sample prints 50B and 50C with different color intensities for the specified color and the base color. Sample print 50B shown in Figure 4B is an example where specified color portion 51B is dark and base color portion 52B is also dark. Sample print 50C shown in Figure 4C is an example where specified color portion 51C is light and base color portion 52C is also light.

[0040] The control unit 11 automatically determines the intervals (amounts of change) of each color component in the plurality of color patches based on the designated color and the background color.

[0041] The control unit 11 determines whether the specified printing color is within or outside the color gamut of the printing device 30. The range of the color gamut of the printing device 30 is stored in advance in the storage unit 15. If the control unit 11 determines that the specified printing color is outside the color gamut of the printing device 30, it converts the specified printing color into a color within the color gamut of the printing device 30. For example, the control unit 11 converts the designated printing color into a color within the color gamut of the printing device 30 so as to maintain the lightness of the designated printing color (maintaining lightness). "Maintaining lightness" means keeping the lightness as small as possible, and does not mean strictly not changing the lightness. Furthermore, the control unit 11 converts the designated printing color into a color within the color gamut of the printing device 30 so as to maintain the saturation of the designated printing color (maintaining saturation). "Maintaining saturation" means keeping the saturation as small as possible, and does not mean strictly leaving the saturation unchanged. Furthermore, the control unit 11 converts the designated printing color into a color within the color gamut of the printing device 30 so that the color difference before and after conversion is minimized (minimum color difference).

[0042] 5 shows an example in which a specified printing color 62 is outside the color gamut 61 of the printing device 30 in a color space 60. The control unit 11 adjusts the specified printing color 62 so that it is within the color gamut.

[0043] The control unit 11 repeatedly creates a color chart (prints the color chart using the printing device 30) and selects a color patch of a color closest to the specified color. The control unit 11 automatically determines the intervals between each color component in the plurality of color patches included in the color chart to be printed next, based on a color patch selected from the plurality of color patches included in the color chart printed in the previous step.

[0044] The control unit 11 causes the storage unit 15 (history storage means) to store the history of the selected color patch and the color chart containing the selected color patch. The control unit 11 causes the printing device 30 to reprint a designated color chart from among the color charts stored in the storage unit 15. The control unit 11 again selects a color patch of a color closest to the specified color from among the plurality of color patches included in the reprinted color chart.

[0045] The control unit 11 acquires colorimetric data measured by the inline colorimeter 35 from the printing device 30 via the communication unit 14. The colorimetric data includes colorimetric values ​​obtained by measuring each of the multiple color patches included in the color chart printed by the printing unit 32. The control unit 11 selects a color patch having the smallest color difference from the designated color based on the color measurement values ​​corresponding to each of the plurality of color patches obtained by the in-line colorimeter 35.

[0046] The control unit 11 sets the first selection unit (automatic selection) or the second selection unit (manual selection) as the selection unit. That is, the control unit 11 functions as a setting unit. When automatic selection is set, the control unit 11 selects the color patch with the smallest color difference from the designated color based on the color measurement values ​​corresponding to each of the multiple color patches obtained by the in-line colorimeter 35. When manual selection is set, the control unit 11 accepts the result of visual judgment by the operator and selects a color patch whose color is closest to the specified color.

[0047] The printing device 30 includes a control unit 31, a printing unit 32, a communication unit 33, a storage unit 34, an in-line colorimeter 35, etc. The units constituting the printing device 30 are connected by a bus.

[0048] The control unit 31 includes a CPU, RAM, etc. The control unit 31 comprehensively controls the processing operations of each unit of the printing device 30. Specifically, the CPU reads out various processing programs stored in the storage unit 34, loads them into the RAM, and performs various processes in cooperation with the programs.

[0049] The printing unit 32 prints on paper using color materials (toner, ink, etc.) of four color components (process colors): cyan, magenta, yellow, and black. The printing method of the printing unit 32 is not particularly limited and may be an electrophotographic method, an inkjet method, or the like.

[0050] The communication unit 33 is configured by a network interface, etc. The communication unit 33 transmits and receives data to and from an external device (such as the color adjustment device 10) connected via a communication line 102 including a LAN, a WAN, etc.

[0051] The storage unit 34 is configured with an HDD, SSD, non-volatile semiconductor memory, etc. The storage unit 34 stores various processing programs, data necessary for executing the programs, etc. For example, the storage unit 34 stores a specified color LUT 341. The specified color LUT 341 is a lookup table that associates, when the color to be printed is a specified color, with what combination of color components (CMYK values) the specified color is to be output.

[0052] The inline colorimeter 35 measures the color of the image on the paper printed by the printing unit 32 and outputs color measurement values. In particular, the inline colorimeter 35 measures the color of a plurality of color patches included in the printed color chart.

[0053] Next, the operation of the color adjustment device 10 will be described. 6 is a flowchart showing the color adjustment process executed by the color adjustment device 10. The color adjustment process is a process for finding device values ​​(CMYK values) corresponding to a specified color in order to match the specified color. The color adjustment process is realized by software processing through cooperation between the CPU of the control unit 11 and a color adjustment processing program 151 stored in the storage unit 15.

[0054] First, the operator measures the color of the designated color portion of the sample printout using the colorimeter 20. The control unit 11 of the color adjustment device 10 receives the colorimetric value (L * a * b *value) is acquired (step S1).

[0055] Next, the worker measures the color of the background color portion of the sample print using the colorimeter 20. The control unit 11 of the color adjustment device 10 receives the colorimetric value (L * a * b * value) is obtained (step S2).

[0056] Next, the control unit 11 executes a first candidate color calculation process (step S3). The first candidate color calculation process is a process for calculating the CMYK values ​​of each color patch in consideration of the background color.

[0057] Here, the first candidate color calculation process will be described with reference to Fig. 7. In the first candidate color calculation process, the control unit 11 calculates the lightness L of the base color and the designated printing color. * The color interval of each color patch included in the color chart is determined based on the lightness L * This is an example of determining whether the base color and the designated printing color are dark or light using the above formula.

[0058] First, the control unit 11 * a * b * value, the L of the base color * a * b * The color is converted into a color (designated printing color) that takes the value into consideration (step S11). In theory, the designated color is realized by placing the designated printing color on paper with the base color.

[0059] Next, the control unit 11 sets the designated printing color (L * a * b * It is determined whether the value is outside the color gamut of the printing device 30 (step S12). If the designated printing color is outside the color gamut of the printing device 30 (step S12; YES), the control unit 11 converts the designated printing color into a color within the color gamut of the printing device 30 according to predetermined criteria (step S13). Predetermined criteria include maintaining lightness, maintaining saturation, and minimizing color difference. The criteria used here are stored in the storage unit 15. If the designated printing color is converted into a color within the color gamut of the printing device 30 in step S13, the converted designated printing color is thereafter treated as the "designated printing color."

[0060] After step S13, or if the specified printing color is within the color gamut of the printing device 30 in step S12 (step S12; NO), the process proceeds to step S14. In step S14, the control unit 11 * is equal to or greater than a first threshold value. The first threshold value is a predetermined value and is stored in the storage unit 15.

[0061] Base color L * If the value is equal to or greater than the first threshold value (step S14; YES), the control unit 11 * It is determined whether or not the second threshold value is equal to or greater than the second threshold value (step S15). The second threshold value is a predetermined value and is stored in the storage unit 15. Printing color L * If the difference is equal to or greater than the second threshold (step S15; YES), the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 3% (step S16). That is, if both the base color and the designated printing color are relatively light, the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 3%. Specifically, the control unit 11 uses the printer profile of the printing device 30 to determine the L of the designated printing color. * a * b * The control unit 11 generates a plurality of combinations of CMYK values ​​by dividing the C, M, Y, and K values ​​by 3% intervals (step widths) with the CMYK value corresponding to the specified printing color as the center (reference).

[0062] In step S15, the L designated color for printing is * is less than the second threshold (step S15; NO), the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 5% (step S17). That is, when the base color is relatively light and the specified printing color is relatively dark, the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 5%. Specifically, the control unit 11 generates a plurality of combinations of CMYK values ​​by allocating values ​​at 5% intervals for each of the C, M, Y, and K values, centered around the CMYK value corresponding to the specified printing color.

[0063] In step S14, the base color L * If it is less than the first threshold value (step S14; NO), the control unit 11 * It is determined whether or not is equal to or greater than the second threshold value (step S18). Printing color L * is equal to or greater than the second threshold (step S18; YES), the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 7% (step S19). That is, if the base color is relatively dark and the specified printing color is relatively light, the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 7%. Specifically, the control unit 11 generates a plurality of combinations of CMYK values ​​by allocating values ​​at 7% intervals for each of the C, M, Y, and K values, centered around the CMYK value corresponding to the specified printing color.

[0064] In step S18, the L designated color for printing is * is less than the second threshold (step S18; NO), the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 10% (step S20). That is, when both the base color and the designated printing color are relatively dark, the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 10%. Specifically, the control unit 11 generates a plurality of combinations of CMYK values ​​by allocating values ​​at 10% intervals for each of the C, M, Y, and K values, centered around the CMYK value corresponding to the designated printing color. After step S16, step S17, step S19, or step S20, the first candidate color calculation process ends.

[0065] Returning to FIG. 6, the control unit 11 generates print data for the color chart (step S4). Specifically, the control unit 11 generates data for printing a color chart including each color patch based on the CMYK values ​​(candidate colors) of each color patch calculated in step S3. The arrangement of each color patch in the color chart is not particularly limited. For example, the control unit 11 may arrange each color patch so that the value of a certain color component gradually changes at predetermined intervals along one direction in the color chart.

[0066] 8 on the display unit 13. The adjustment screen 131 includes a color chart display area 71, a center color patch 72, a center color patch display area 73, a patch coordinate display area 74, a CMYK value display area 75, a step width display area 76, a print start button 77, etc.

[0067] The color chart display area 71 displays the color chart to be printed based on the print data generated in step S4. The center color patch 72 is a color patch of a color that is the center (reference) of the color chart. The center color patch 72 is a color patch that corresponds to a designated color for printing. The center color patch display area 73 displays the color of the center color patch. The coordinates of the center color patch in the color chart are displayed in the patch coordinate display area 74. Here, the coordinates of the center color patch are shown as a combination of columns A to I and rows 1 to 9. In the CMYK value display area 75, the CMYK values ​​corresponding to the center color patch are displayed. The step width (interval) of the CMYK values ​​based on the center color patch is displayed in the step width display area 76. The step width is a value that is automatically determined in the first candidate color calculation process. The print start button 77 is a button for instructing printing of a color chart. When the print start button 77 is pressed, the process proceeds to step S5.

[0068] Next, the control unit 11 transmits the print data to the printing device 30 via the communication unit 14, and causes the printing device 30 to print the color chart (step S5). The control unit 31 of the printing device 30 causes the printing unit 32 to print a color chart based on the print data. The color chart is printed on the same paper as the sample print.

[0069] Next, the control unit 11 of the color adjustment device 10 selects a color patch of a color closest to the designated color of the sample print from among the plurality of color patches included in the color chart (step S6).

[0070] When automatic selection (first selection means) is set, the control unit 11 of the color adjustment device 10 acquires colorimetric values ​​corresponding to each of the multiple color patches obtained by the inline colorimeter 35 from the printing device 30 via the communication unit 14. These colorimetric values ​​are values ​​measured by the inline colorimeter 35 when a color chart is printed on the printing device 30. For example, colorimetric data is transmitted from the printing device 30 to the color adjustment device 10 in a state in which the coordinates of the color patches correspond to the colorimetric values ​​of the color patches. The control unit 11 can identify the colorimetric values ​​of each color patch based on the coordinates of each color patch. Based on the colorimetric values ​​corresponding to each of the multiple color patches, the control unit 11 selects a color patch with the smallest color difference from the specified color. After automatic selection, if the operator finds a color patch that is more suitable than the color patch with the smallest color difference from the designated color, the operator may be able to manually select another color patch.

[0071] When manual selection (second selection means) is set or when the printing device 30 is not equipped with an inline colorimeter 35, the worker visually checks the printed color chart. The worker compares the color of each color patch with the specified color of the sample printout and finds the color patch whose color is closest to the specified color. The worker selects the color patch whose color is closest to the specified color via the operation unit 12. The control unit 11 accepts the result of the worker's visual judgment and selects the color patch whose color is closest to the specified color.

[0072] Next, the control unit 11 saves the adjustment history in the storage unit 15 (step S7). Specifically, the control unit 11 stores information about the printed color chart, information about the selected color patch, etc. in the adjustment history table 152.

[0073] 9 shows an example of the adjustment history table 152. The adjustment history table 152 stores, for each adjustment history, the color name, the CMYK value of the center color patch, the coordinates of the selected color patch, the CMYK value of the selected color patch, the step width of the color patch, the adjustment method for the out-of-gamut color, and the like, in association with each other. The color name is the name of the color to be adjusted. The color name can be arbitrarily specified by the user for the combination of the specified color and the background color. The CMYK values ​​of the center color patch are the CMYK values ​​corresponding to the color patch that is the center (reference) of the color chart. The coordinates of the selected color patch are the coordinates of the color patch selected as the color patch whose color is closest to the specified color. The CMYK values ​​of the selected color patch are the CMYK values ​​that correspond to the selected color patch. The step width of the color patch is the interval between the CMYK values ​​in each color patch included in the color chart. The method for adjusting colors outside the color gamut is the adjustment standard (maintaining brightness, maintaining saturation, minimizing color difference, etc.) for colors outside the color gamut when printing a color chart.

[0074] Next, the control unit 11 determines whether to end the adjustment (step S8). For example, the operator selects whether to end the adjustment or to perform additional adjustment via the operation unit 12. The control unit 11 determines whether to end the adjustment in accordance with the operator's selection. The control unit 11 causes the display unit 13 to display an adjustment screen 132 (see FIG. 10) or an adjustment screen 133 (see FIG. 11).

[0075] 10 is an example of a case where color patches are automatically selected based on the color measurement results obtained by the in-line colorimeter 35. The adjustment screen 132 includes a color chart display area 81, a selected color patch 82, a selected color patch display area 83, a patch coordinate display area 84, a CMYK value display area 85, and a L * a * b * It includes a value display area 86, a color difference display area 87, an adjustment end button 88, an additional adjustment button 89, and the like.

[0076] The color chart display area 81 displays the color chart printed in the most recent step S5. The selected color patch 82 is the color patch that was automatically selected in the most recent step S6 as the color patch with the smallest color difference from the designated color. The selected color patch display area 83 displays the color of the selected color patch. The patch coordinate display area 84 displays the coordinates of the selected color patch in the color chart. The CMYK value display area 85 displays the CMYK values ​​corresponding to the selected color patch. L * a * b * The value display area 86 displays the L value corresponding to the selected color patch. * a * b * The value is displayed. The color difference display area 87 displays the color difference between the selected color patch and the specified color. The end of adjustment button 88 is a button for instructing the end of adjustment. When the end of adjustment button 88 is pressed, the process proceeds to step S10. The additional adjustment button 89 is a button for instructing additional adjustment. When the additional adjustment button 89 is pressed, the process proceeds to step S9.

[0077] 11 is an example of a case where a color patch is manually selected by an operator. The adjustment screen 133 includes a color chart display area 91, a selected color patch 92, a selected color patch display area 93, a patch coordinate display area 94, a CMYK value display area 95, an adjustment end button 96, an additional adjustment button 97, etc.

[0078] The color chart display area 91 displays the color chart printed in the most recent step S5. The selected color patch 92 is the color patch selected by the operator in the most recent step S6 as the color patch whose color is closest to the specified color. The selected color patch display area 93 displays the color of the selected color patch. The patch coordinate display area 94 displays the coordinates of the selected color patch in the color chart. The CMYK value display area 95 displays the CMYK values ​​corresponding to the selected color patch. The end of adjustment button 96 is a button for instructing the end of adjustment. When the end of adjustment button 96 is pressed, the process proceeds to step S10. The additional adjustment button 97 is a button for instructing additional adjustment. When the additional adjustment button 97 is pressed, the process proceeds to step S9.

[0079] If the adjustment is not to be ended in step S8 (step S8; NO), that is, if the adjustment is not sufficient, the process proceeds to step S9. In step S9, the control unit 11 calculates candidate colors centered on the selected color patch. Specifically, the control unit 11 automatically determines the intervals between each color component in the multiple color patches based on the color patch selected in the most recent step S6. For example, the control unit 11 narrows the intervals between each color component in the multiple color patches. The control unit 11 generates multiple combinations of CMYK values ​​by allocating values ​​at the determined intervals for each of the C, M, Y, and K values, centered on the CMYK value corresponding to the selected color patch.

[0080] After step S9, the process returns to step S4, and the processes from step S4 onwards are repeated. Specifically, in step S4, the control unit 11 generates data for printing a color chart including each color patch based on the CMYK values ​​(candidate colors) of each color patch calculated in step S9. Here, the control unit 11 causes the display unit 13 to display the adjustment screen 131 shown in Fig. 8. Details of the adjustment screen 131 are as described above. However, the center color patch 72 is the color patch selected in the most recent step S6. The step width displayed in the step width display area 76 is the interval automatically determined in the most recent step S9.

[0081] In this way, the control unit 11 creates a new color chart including multiple color patches and repeats the process of selecting a color patch whose color is closest to the specified color. Specifically, the control unit 11 repeats the process until one of the color patches in the color chart becomes close to the specified color to an acceptable extent.

[0082] In step S8, if the adjustment is to be ended (step S8; YES), the control unit 11 registers the adjustment value (step S10). Specifically, the control unit 11 associates the specified color name with the CMYK value corresponding to the last selected color patch, and transmits them to the printing device 30 via the communication unit 14. The control unit 31 of the printing device 30 associates the designated color name with the CMYK values ​​corresponding to the most recently selected color patch, and stores them in the designated color LUT 341 of the storage unit 34. After this, when the control unit 31 receives an instruction to print a designated color, it uses the updated designated color LUT 341 to convert the designated color to CMYK values, and performs printing using these CMYK values. This completes the color adjustment process.

[0083] If the operator has already made adjustments multiple times, he or she can return to a previous color chart, which is the result of previous adjustments, and make further adjustments. When the operator instructs the use of the adjustment history through the operation unit 12, the control unit 11 reads the adjustment history table 152 (see FIG. 9 ) from the storage unit 15 and displays the adjustment history table 152 in tabular form on the display unit 13. Each record stored in the adjustment history table 152 corresponds to the color chart printed at that time. The operator operates the operation unit 12 to specify one of the adjustment histories (color charts) displayed on the display unit 13. The control unit 11 generates print data for the color chart based on the "CMYK values ​​of the center color patch" and "color patch step width" included in the record corresponding to the specified adjustment history (color chart). The control unit 11 transmits the print data to the printing device 30 via the communication unit 14 and causes the printing device 30 to reprint the color chart. The control unit 11 then selects a color patch of a color closest to the specified color of the sample print from the multiple color patches included in the reprinted color chart. The selection method may be automatic or manual, as in step S6. The subsequent processing is the same as in the color adjustment processing.

[0084] As described above, according to the first embodiment, the control unit 11 of the color adjustment device 10 determines a designated printing color by shifting the designated color by the amount of the background color of the paper on which the color chart is printed. The control unit 11 calculates the values ​​of each color component corresponding to each of the multiple color patches so as to represent the designated printing color and colors close to the designated printing color. In this manner, the control unit 11 causes the printing device 30 to print a color chart including multiple color patches. The printed multiple color patches are likely to be colors close to the designated color because the background color is taken into account. Therefore, the control unit 11 can achieve skill-free color adjustment of the designated color even when printing on paper other than white.

[0085] The control unit 11 calculates the value of each color component corresponding to each of the multiple color patches based on the absolute color values ​​of the specified color and the background color obtained by colorimetry, thereby enabling the control unit 11 to generate print data for a color chart that takes the background color into consideration.

[0086] The control unit 11 automatically determines the intervals between the color components in the plurality of color patches based on the designated color and the background color. For example, the control unit 11 automatically determines the intervals between the color components in the plurality of color patches based on the lightness L of the designated color for printing and the background color. * The control unit 11 can efficiently generate print data for a color chart according to the densities of the designated printing colors and the background colors.

[0087] If the control unit 11 determines that the specified printing color is outside the color gamut of the printing device 30, it converts the specified printing color into a color within the color gamut of the printing device 30. For example, the control unit 11 can convert the specified printing color into a color within the color gamut of the printing device 30 while maintaining the lightness of the specified printing color. The control unit 11 can also convert the specified printing color into a color within the color gamut of the printing device 30 while maintaining the saturation of the specified printing color. The control unit 11 can convert the specified printing color into a color within the color gamut of the printing device 30 while minimizing the color difference before and after conversion.

[0088] The control unit 11 automatically determines the spacing between each color component in the multiple color patches included in the color chart to be printed next, based on a color patch selected from the multiple color patches included in the color chart. This allows the control unit 11 to repeat printing of the color chart and selection of color patches while automatically changing the spacing between each color component in the multiple color patches.

[0089] The control unit 11 causes the printing device 30 to reprint the color chart specified by the operator from the color charts stored in the storage unit 15. The control unit 11 then reselects the color patch closest to the specified color from the multiple color patches included in the reprinted color chart. In this way, the control unit 11 can readjust the specified color using past history.

[0090] When automatic selection of color patches is set, the control unit 11 can select the color patch with the smallest color difference from the specified color based on the colorimetric values ​​corresponding to each of the multiple color patches obtained by the inline colorimeter 35. When manual selection of a color patch is set, the control unit 11 can select a color patch of a color closest to the specified color by accepting the result of visual judgment by the operator.

[0091] In step S6 of the color adjustment process, when automatic selection of color patches is set, the control unit 11 uses the colorimetric values ​​obtained by the inline colorimeter 35. Alternatively, the control unit 11 may obtain colorimetric values ​​obtained by measuring the color of each color patch included in the color chart with the colorimeter 20.

[0092] Furthermore, in step S8 of the color adjustment process, the control unit 11 may automatically determine whether or not to end the adjustment. For example, the control unit 11 determines to end the adjustment when the color difference between the color patch selected in step S6 and the designated color becomes equal to or less than a predetermined value.

[0093] [Second embodiment] Next, a second embodiment to which the present invention is applied will be described. The printing system in the second embodiment has a configuration similar to that of the printing system 100 shown in the first embodiment. Therefore, the same components as those in the first embodiment are designated by the same reference numerals, and illustrations and descriptions thereof will be omitted. The configuration and processing characteristic of the second embodiment will be described below.

[0094] The color adjustment process executed by the color adjustment device 10 of the second embodiment is the same as the color adjustment process in the first embodiment (see FIG. 6). However, the control unit 11 of the color adjustment device 10 executes a second candidate color calculation process instead of the first candidate color calculation process (see FIG. 7) in step S3. In the second candidate color calculation process, the control unit 11 calculates the absolute color value L * a * b * Using the value, it is determined whether the base color and the designated printing color are dark or light with white as the reference.

[0095] FIG. 12 is a flowchart showing the second candidate color calculation process. The processing of steps S21 to S23 is the same as the processing of steps S11 to S13 in the first candidate color calculation processing (see FIG. 7), and therefore a description thereof will be omitted.

[0096] After step S23, or in step S22, if the specified printing color is within the color gamut of the printing device 30 (step S22; NO), the process proceeds to step S24. In step S24, the control unit 11 determines whether the base color (L * a * b * The color difference ΔE1 between the color (value) and white is calculated. Next, the control unit 11 sets the designated printing color (L * a * b * The color difference ΔE2 between the color (value) and white is calculated (step S25).

[0097] Next, the control unit 11 determines whether the color difference ΔE1 between the background color and white is less than a third threshold value (step S26). The third threshold value is a predetermined value and is stored in the storage unit 15. If the color difference ΔE1 between the background color and white is less than the third threshold (step S26; YES), the control unit 11 determines whether the color difference ΔE2 between the designated printing color and white is less than a fourth threshold (step S27). The fourth threshold is a predetermined value stored in the storage unit 15. If the color difference ΔE2 between the specified printing color and white is less than the fourth threshold value (step S27; YES), the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 3% (step S28). That is, if both the base color and the specified printing color are relatively light, the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 3%. Specifically, the control unit 11 generates multiple combinations of CMYK values ​​by allocating values ​​at 3% intervals for each of the C, M, Y, and K values, centered around the CMYK value corresponding to the specified printing color.

[0098] In step S27, if the color difference ΔE2 between the specified printing color and white is equal to or greater than the fourth threshold value (step S27; NO), the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 5% (step S29). That is, if the base color is relatively light and the specified printing color is relatively dark, the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 5%. Specifically, the control unit 11 generates a plurality of combinations of CMYK values ​​by allocating values ​​at 5% intervals for each of the C, M, Y, and K values, centered around the CMYK value corresponding to the specified printing color.

[0099] In step S26, if the color difference ΔE1 between the background color and white is equal to or greater than the third threshold (step S26; NO), the control unit 11 determines whether the color difference ΔE2 between the specified printing color and white is less than the fourth threshold (step S30). If the color difference ΔE2 between the specified printing color and white is less than the fourth threshold value (step S30; YES), the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 7% (step S31). That is, if the base color is relatively dark and the specified printing color is relatively light, the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 7%. Specifically, the control unit 11 generates multiple combinations of CMYK values ​​by allocating values ​​at 7% intervals for each of the C, M, Y, and K values, centered around the CMYK value corresponding to the specified printing color.

[0100] In step S30, if the color difference ΔE2 between the specified printing color and white is equal to or greater than the fourth threshold value (step S30; NO), the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 10% (step S32). That is, if both the base color and the specified printing color are relatively dark, the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 10%. Specifically, the control unit 11 generates a plurality of combinations of CMYK values ​​by allocating values ​​at 10% intervals for each of the C, M, Y, and K values, centered around the CMYK value corresponding to the specified printing color. After step S28, step S29, step S31, or step S32, the second candidate color calculation process ends.

[0101] As described above, according to the second embodiment, similar to the first embodiment, the control unit 11 of the color adjustment device 10 can achieve skill-less color adjustment for a specified color even when printing on paper other than white.

[0102] The control unit 11 automatically determines the spacing between each color component in the multiple color patches based on the designated color and the background color. In the second embodiment, the control unit 11 determines whether the designated printing color and the background color are dark or light based on the color difference ΔE2 between the designated printing color and white and the color difference ΔE1 between the background color and white. The control unit 11 can efficiently generate print data for the color chart according to the darkness of the designated printing color and the background color.

[0103] [Third embodiment] Next, a third embodiment to which the present invention is applied will be described. The printing system in the third embodiment has a configuration similar to that of the printing system 100 shown in the first embodiment. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals, and illustrations and descriptions thereof will be omitted. The configuration and processing characteristic of the third embodiment will be described below.

[0104] The color adjustment process executed by the color adjustment device 10 of the third embodiment is similar to the color adjustment process of the first embodiment (see FIG. 6). However, the control unit 11 of the color adjustment device 10 executes a third candidate color calculation process instead of the first candidate color calculation process of step S3 (see FIG. 7). In the third candidate color calculation process, the control unit 11 converts the designated color (designated printing color) adjusted by the amount of the base color into a CMYK value, and uses this CMYK value to determine whether the designated printing color is dark or light.

[0105] FIG. 13 is a flowchart showing the third candidate color calculation process. The processing of steps S41 to S43 is the same as the processing of steps S11 to S13 in the first candidate color calculation processing, and therefore a description thereof will be omitted.

[0106] After step S43, or if the specified printing color is within the color gamut of the printing device 30 in step S42 (step S42; NO), the process proceeds to step S44. In step S44, the control unit 11 uses the printer profile of the printing device 30 to determine the specified printing color (L * a * b * values) into the values ​​of each color component (CMYK values) in the printing device 30.

[0107] Next, the control unit 11 selects the L * is equal to or greater than the first threshold value (step S45). Here, the same threshold value as in step S14 of the first candidate color calculation process (see FIG. 7) is used, but a different value may also be used. Base color L *If is equal to or greater than the first threshold (step S45; YES), the control unit 11 determines whether the sum of the CMYK values ​​of the specified printing color is less than a fifth threshold (step S46). The sum of the CMYK values ​​is the sum of the C value, M value, Y value, and K value. The fifth threshold is a predetermined value that is stored in the storage unit 15. If the sum of the CMYK values ​​of the specified printing color is less than the fifth threshold (step S46; YES), the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 3% (step S47). That is, if both the base color and the specified printing color are relatively light, the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 3%. Specifically, the control unit 11 generates multiple combinations of CMYK values ​​by allocating values ​​at 3% intervals for each of the C, M, Y, and K values, centered around the CMYK value corresponding to the specified printing color.

[0108] In step S46, if the sum of the CMYK values ​​of the specified printing color is equal to or greater than the fifth threshold (step S46; NO), the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 5% (step S48). That is, if the base color is relatively light and the specified printing color is relatively dark, the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 5%. Specifically, the control unit 11 generates a plurality of combinations of CMYK values ​​by allocating values ​​at 5% intervals for each of the C, M, Y, and K values, centered on the CMYK value corresponding to the specified printing color.

[0109] In step S45, the base color L * If the sum of the CMYK values ​​of the specified printing color is less than the fifth threshold (step S49), the control unit 11 determines whether the sum of the CMYK values ​​of the specified printing color is less than the fifth threshold (step S49). If the sum of the CMYK values ​​of the specified printing color is less than the fifth threshold (step S49; YES), the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 7% (step S50). That is, if the base color is relatively dark and the specified printing color is relatively light, the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 7%. Specifically, the control unit 11 generates multiple combinations of CMYK values ​​by allocating values ​​at 7% intervals for each of the C, M, Y, and K values, centered around the CMYK value corresponding to the specified printing color.

[0110] In step S49, if the sum of the CMYK values ​​of the specified printing color is equal to or greater than the fifth threshold (step S49; NO), the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 10% (step S51). That is, if both the base color and the specified printing color are relatively dark, the control unit 11 determines the interval between the CMYK values ​​of each color patch to be 10%. Specifically, the control unit 11 generates a plurality of combinations of CMYK values ​​by allocating values ​​at 10% intervals for each of the C, M, Y, and K values, centered on the CMYK value corresponding to the specified printing color. After step S47, step S48, step S50, or step S51, the third candidate color calculation process ends.

[0111] As described above, according to the third embodiment, similar to the first embodiment, the control unit 11 of the color adjustment device 10 can achieve skill-less color adjustment for a specified color even when printing on paper other than white.

[0112] The control unit 11 automatically determines the intervals between each color component in the multiple color patches based on the designated color and the background color. In the third embodiment, the control unit 11 determines whether the designated printing color is dark or light based on the sum of the CMYK values ​​of the designated printing color. The control unit 11 determines the lightness L of the background color. * The control unit 11 can efficiently generate print data for a color chart according to the specified printing color and the density of the background color.

[0113] In the third candidate color calculation process, the control unit 11 calculates the lightness L of the background color. * Alternatively, control unit 11 may determine whether the background color is dark or light using the color difference between the background color and white, as in the second candidate color calculation process (see FIG. 12).

[0114] [Fourth embodiment] Next, a fourth embodiment to which the present invention is applied will be described. The printing system in the fourth embodiment has a configuration similar to that of the printing system 100 shown in the first embodiment. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals, and illustrations and descriptions thereof will be omitted. The configuration and processing characteristic of the fourth embodiment will be described below.

[0115] In the first to third embodiments, the control unit 11 of the color adjustment device 10 has been described as acquiring the absolute color values ​​of the specified color and the absolute color values ​​of the base color from the colorimeter 20. In the fourth embodiment, the absolute color values ​​of the specified color and the absolute color values ​​of the base color are stored in the storage unit 15 of the color adjustment device 10 as pre-registered data.

[0116] The storage unit 15 of the color adjustment device 10 stores a designated color table and a base color table. The specified color table contains the color name, L, * a * b * The values ​​and CMYK values ​​are associated. The color name is the name given to each designated color. L * a * b * The values ​​are the absolute color values ​​for each specified color. The CMYK values ​​are the values ​​of each color component in the printing device 30 for reproducing each specified color in the printing device 30 .

[0117] The base color table contains the color name, L, and * a * b *The values ​​and CMYK values ​​are associated. The color name is the name of the color given to each base color. L * a * b * The values ​​are absolute color values ​​for each base color. The CMYK values ​​are values ​​of each color component in the printing device 30 for reproducing each base color in the printing device 30 .

[0118] The color adjustment process executed by the color adjustment device 10 of the fourth embodiment is similar to the color adjustment process in the first embodiment (see FIG. 6). However, the contents of the processes in steps S1 and S2 are different from the processes in the first embodiment.

[0119] In step S1, the control unit 11 of the color adjustment device 10 selects the L of the designated color selected by the operator from the designated color table stored in the storage unit 15. * a * b * Get the value.

[0120] For example, the control unit 11 causes the display unit 13 to display a designated color list screen 134 shown in Fig. 14 based on the designated color table. The designated color list screen 134 displays, for each designated color, a color name, L * a * b * The value, CMYK value, and color patch are displayed. Color name, L * a * b * The values ​​and CMYK values ​​are stored in the specified color table. * a * b * An image simulating a color patch of the specified color identified by the value is displayed.

[0121] The operator selects one of the designated colors from the designated color list screen 134 via the operation unit 12. The control unit 11 selects the L corresponding to the designated color selected by the operator. * a * b * The value is retrieved from the specified color table.

[0122] In step S2, the control unit 11 selects the L of the background color selected by the operator from the background color table stored in the storage unit 15. * a * b * Get the value.

[0123] For example, the control unit 11 causes the display unit 13 to display a background color list screen 135 shown in Fig. 15 based on the background color table. The background color list screen 135 displays, for each background color, a color name, L * a * b * The value, CMYK value, and color patch are displayed. Color name, L * a * b * The values ​​and CMYK values ​​are stored in the base color table. * a * b * An image simulating a color patch of the background color specified by the value is displayed.

[0124] The operator selects one of the background colors from the background color list screen 135 via the operation unit 12. The control unit 11 selects the L corresponding to the background color selected by the operator. * a * b * The value is taken from the base color table.

[0125] Color value of the specified color and the background color (L * a * b * The only difference is the method of acquiring the value, and other processing is the same as in the first embodiment.

[0126] As described above, according to the fourth embodiment, similar to the first embodiment, the control unit 11 of the color adjustment device 10 can achieve skill-less color adjustment for a specified color even when printing on paper other than white.

[0127] The operator can select a designated color and a background color from data pre-registered in the storage unit 15. The control unit 11 acquires the absolute color values ​​of the designated color and the background color from the data pre-registered in the storage unit 15. The control unit 11 calculates the values ​​of each color component corresponding to each of the multiple color patches based on the absolute color values ​​of the designated color and the absolute color values ​​of the background color. This allows the control unit 11 to generate print data for a color chart that takes the background color into consideration.

[0128] [Fifth embodiment] Next, a fifth embodiment to which the present invention is applied will be described. The printing system in the fifth embodiment has a configuration similar to that of the printing system 100 shown in the first embodiment. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals, and illustrations and descriptions thereof will be omitted. The configuration and processing characteristic of the fifth embodiment will be described below.

[0129] The control unit 11 of the color adjustment device 10 sets the first mode or the second mode. That is, the control unit 11 functions as a setting unit. The first mode is, for example, a mode for general operators. The second mode is, for example, a mode for color adjustment experts.

[0130] FIG. 16 shows the settings for the first mode and the second mode. In the first mode, the control unit 11 automatically determines the interval (step width) between each color component in the plurality of color patches. In the first mode, when the control unit 11 determines that the specified printing color is outside the color gamut of the printing device 30, it automatically converts the specified printing color to a color within the color gamut of the printing device 30 according to a predetermined standard. In the example shown in Fig. 16, it is set to convert an out-of-gamut color to a color within the color gamut so that the color difference before and after conversion is minimized. In the first mode, the control unit 11 automatically selects a color patch that has the smallest color difference from the designated color, based on the color measurement values ​​corresponding to each of the multiple color patches obtained by the in-line colorimeter 35.

[0131] In the second mode, the control unit 11 determines the interval (step width) between each color component in the plurality of color patches based on a manual instruction from the operator. In the second mode, if the control unit 11 determines that the specified printing color is outside the color gamut of the printing device 30, it converts the specified printing color into a color within the color gamut of the printing device 30 according to a standard manually set by the operator. In the example shown in Fig. 16, the operator can select one of the standards: maintain lightness, maintain saturation, or minimize color difference. In the second mode, the control unit 11 accepts the result of the worker's visual judgment and selects a color patch whose color is closest to the specified color.

[0132] The color adjustment process executed by the color adjustment device 10 of the fifth embodiment is basically the same as the color adjustment process in the first embodiment (see FIG. 6). However, in the color adjustment device 10, either the first mode or the second mode is set before the color adjustment process is executed. For example, when an operator selects the first mode or the second mode by operating the operation unit 12, the control unit 11 sets either the first mode or the second mode.

[0133] When the first mode is set, in step S13 of the first candidate color calculation process (see FIG. 7), the control unit 11 follows the criteria (see FIG. 16) set for the "out-of-gamut color adjustment method" of the first mode. For example, the control unit 11 converts the specified printing color to a color within the color gamut of the printing device 30 so that the color difference before and after conversion is minimized. When the first mode is set, the control unit 11 automatically determines the interval (step width) of each color component in the color patch, as shown in steps S14 to S20 of the first candidate color calculation process (see FIG. 7). When the first mode is set, in step S6 of the color adjustment process (see FIG. 6), the control unit 11 automatically selects the color patch with the smallest color difference from the specified color based on the colorimetric values ​​corresponding to each of the multiple color patches.

[0134] When the second mode is set, in step S13 of the first candidate color calculation process (see FIG. 7), control unit 11 causes display unit 13 to display options of maintaining lightness, maintaining saturation, and minimizing color difference. Control unit 11 accepts the operator's selection of criteria for adjusting colors outside the color gamut via operation unit 12. Control unit 11 converts the specified printing color into a color within the color gamut of printing device 30 according to the criteria selected by the operator. When the second mode is set, control unit 11 does not perform steps S14 to S20 of the first candidate color calculation process (see FIG. 7). Instead, control unit 11 prompts the operator to specify the interval (step width) of each color component in the color patch via operation unit 12. Control unit 11 generates a plurality of combinations of CMYK values ​​by allocating values ​​for each of the C, M, Y, and K values ​​at intervals specified by the operator, with the CMYK value corresponding to the specified printing color as the center (base). When the second mode is set, in step S6 of the color adjustment process (see FIG. 6), the control unit 11 causes the operator to select a color patch of a color closest to the designated color via the operation unit 12. The control unit 11 accepts the result of the operator's visual judgment and selects a color patch of a color closest to the designated color.

[0135] As described above, according to the fifth embodiment, when the first mode is set, the control unit 11 of the color adjustment device 10 can automatically adjust colors outside the color gamut, set the intervals between color components in color patches, and select color patches. Therefore, the control unit 11 can perform skill-less color adjustment of specified colors even when printing on paper other than white.

[0136] On the other hand, when the second mode is set, the control unit 11 can adjust colors outside the color gamut, set the intervals between each color component in the color patch, and select color patches according to manual instructions from the operator. The control unit 11 can provide color adjustment with a higher degree of freedom for color adjustment experts.

[0137] The above-described embodiments are merely examples of the color adjustment system, color adjustment device, color adjustment method, and program according to the present invention, and are not intended to limit the scope of the present invention. The detailed configuration and operation of each device constituting the system may also be modified as appropriate without departing from the spirit of the present invention. For example, characteristic processes in each embodiment may be combined.

[0138] In each of the above embodiments, the control unit 11 of the color adjustment device 10 determines the intervals between each color component in the color patch to be the same value for each color component. Alternatively, the control unit 11 may determine the intervals between each color component in the color patch to be different values ​​for each color component.

[0139] In the above embodiments, the color components of the printing device 30 are cyan, magenta, yellow, and black, but the present invention is not limited to this. The color components of the printing device 30 can be changed as appropriate depending on the color of the color material used in the printing device 30.

[0140] In each of the above embodiments, the processing performed by the color adjustment device 10 may be performed by another device. In each of the above embodiments, the processing performed by the color adjustment device 10 may be performed by a plurality of devices in cooperation with each other.

[0141] In the above embodiments, the storage unit 15 of the color adjustment device 10 functions as a storage unit that stores the absolute color values ​​of the specified color and the absolute color values ​​of the base color. Alternatively, the absolute color values ​​of the specified color and the absolute color values ​​of the base color may be stored in a storage device external to the color adjustment device 10. In addition, in each of the above embodiments, the storage unit 15 of the color adjustment device 10 functions as a history storage unit that stores the history of selected color patches and color charts that include the selected color patches. Alternatively, the history of selected color patches and color charts that include the selected color patches may be stored in a storage device external to the color adjustment device 10.

[0142] The computer-readable medium for storing the program for executing each process is not limited to the above examples. A carrier wave may also be used as a medium for providing program data via a communication line.

[0143] Although the embodiments of the present invention have been described and illustrated in detail above, the disclosed embodiments are intended for purposes of illustration and example only, and not for purposes of limitation. The scope of the present invention should be interpreted by the terms of the following claims. [Explanation of symbols]

[0144] 10 Color adjustment device 11 Control section 12 Control section 13 Display section 14 Communications Department 15 Storage section 16 IF Section 20 Colorimeter 30 Printing device 31 Control Unit 32 Printing Department 33 Communications Department 34 Storage section 35 Inline colorimeter 100 Printing Systems 151 Color adjustment processing program 152 Adjustment History Table 341 Specified color LUT

Claims

1. a chart creation means for causing the printing device to print a color chart including a plurality of color patches in which the values ​​of each color component in the printing device are changed for a specified color; a selection means for selecting a color patch of a color closest to the specified color from the plurality of color patches included in the printed color chart; a color adjustment unit that performs color adjustment of the designated color printed by the printing device based on the values ​​of each color component corresponding to the selected color patch; A color adjustment system comprising: The chart creation means determines a designated printing color by shifting the designated color by the amount of the background color of the paper on which the color chart is printed, and calculates the values ​​of each color component corresponding to each of the plurality of color patches so as to express the designated printing color and its neighboring colors.

2. a storage means for storing absolute color values ​​of the designated color and absolute color values ​​of the base color; the absolute color values ​​of the designated color and the absolute color values ​​of the base color stored in the storage means are data obtained by measuring the designated color and the base color, respectively, or data registered in advance; the chart creation means calculates a value of each color component corresponding to each of the plurality of color patches based on the absolute color value of the specified color and the absolute color value of the base color. The color adjustment system of claim 1 .

3. the chart creation means automatically determines intervals between the color components in the plurality of color patches based on the designated color and the base color. The color adjustment system of claim 1 .

4. The chart creation means determining whether the specified printing color is within or outside the color gamut of the printing device; When it is determined that the specified printing color is outside the color gamut of the printing device, the specified printing color is converted to a color within the color gamut of the printing device so as to maintain lightness, maintain saturation, or minimize the color difference before and after conversion. The color adjustment system of claim 1 .

5. The printing of the color chart and the selection of a color patch of a color closest to the specified color are repeated, the chart creation means automatically determines intervals between color components in the plurality of color patches included in the color chart to be printed next, based on the color patch selected by the selection means from the plurality of color patches included in the color chart printed in the previous stage; The color adjustment system of claim 1 .

6. a history storage means for storing a history of the color patch selected by the selection means and the color chart including the color patch; the chart creation means causes the printing device to reprint a designated color chart from the color charts stored in the history storage means; the selecting means reselects a color patch having a color closest to the specified color from the plurality of color patches included in the reprinted color chart; The color adjustment system according to claim 5 .

7. a colorimeter for measuring the color of the plurality of color patches included in the printed color chart; the selecting means selects a color patch having a minimum color difference from the designated color based on the colorimetric values ​​corresponding to each of the plurality of color patches obtained by the colorimeter. The color adjustment system of claim 1 .

8. a colorimeter that measures the color of the plurality of color patches included in the printed color chart; a setting means for setting, as the selecting means, a first selecting means for selecting a color patch having a minimum color difference from the designated color based on colorimetric values ​​corresponding to each of the plurality of color patches obtained by the colorimeter, or a second selecting means for selecting a color patch having a color closest to the designated color by receiving a result of visual judgment by an operator; Equipped with The color adjustment system of claim 1 .

9. a colorimeter that measures the color of the plurality of color patches included in the printed color chart; a setting means for setting the first mode or the second mode; Equipped with In the first mode, the chart creation means automatically determines the intervals between the color components in the plurality of color patches; when it is determined that the designated printing color is outside the color gamut of the printing device, the chart creation means automatically converts the designated printing color into a color within the color gamut of the printing device in accordance with a predetermined standard; the selecting means automatically selects a color patch having a minimum color difference from the designated color based on the colorimetric values ​​corresponding to each of the plurality of color patches obtained by the colorimeter; In the second mode, the chart creation means determines intervals between the color components in the plurality of color patches based on manual instructions from an operator; when it is determined that the designated printing color is outside the color gamut of the printing device, the chart creation means converts the designated printing color into a color within the color gamut of the printing device in accordance with a standard manually set by an operator; the selecting means selects a color patch having a color closest to the specified color by receiving a result of visual judgment by an operator. The color adjustment system of claim 1 .

10. a chart creation means for causing the printing device to print a color chart including a plurality of color patches in which the values ​​of each color component in the printing device are changed for a specified color; a selection means for selecting a color patch of a color closest to the specified color from the plurality of color patches included in the printed color chart; a color adjustment unit that performs color adjustment of the designated color printed by the printing device based on the values ​​of each color component corresponding to the selected color patch; A color adjustment device comprising: The chart creation means is a color adjustment device that determines a designated printing color by shifting the designated color by the amount of the background color of the paper on which the color chart is printed, and calculates the values ​​of each color component corresponding to each of the multiple color patches so as to express the designated printing color and its neighboring colors.

11. a chart creation step of causing the printing device to print a color chart including a plurality of color patches in which the values ​​of each color component in the printing device are changed for a specified color; a selection step of selecting a color patch having a color closest to the specified color from the plurality of color patches included in the printed color chart; a color adjustment step of performing color adjustment of the designated color to be printed by the printing device based on the values ​​of each color component corresponding to the selected color patch; A color adjustment method comprising: In the chart creation process, a designated printing color is determined by shifting the designated color by the amount of the background color of the paper on which the color chart is printed, and the color component values ​​corresponding to each of the plurality of color patches are calculated so as to represent the designated printing color and its neighboring colors.

12. Computer, a chart creation means for causing the printing device to print a color chart including a plurality of color patches in which the values ​​of each color component in the printing device are changed for a specified color; a selection means for selecting a color patch of a color closest to the specified color from the plurality of color patches included in the printed color chart; a color adjustment unit that performs color adjustment of the designated color printed by the printing device based on the values ​​of each color component corresponding to the selected color patch; A program for functioning as The chart creation means is a program that determines a designated printing color by shifting the designated color by the amount of the background color of the paper on which the color chart is printed, and calculates the values ​​of each color component corresponding to each of the multiple color patches so as to represent the designated printing color and its neighboring colors.

Images