JP2020047970A - Color chart for color selection, color chart generation method for color selection, color chart generation program for color selection, and color chart generation apparatus for color selection - Google Patents

Abstract

To provide a technology to reduce work to search for a color patch matching a target color.SOLUTION: A first patch group includes a plurality of color patches that include a first color patch and a second color patch and are arranged at a first color difference interval. A second patch group and a third patch group include a plurality of color patches that are arranged at a second color difference interval narrower than the first color difference interval. Provided that color values are coordinate values in a device independent color space, the color values of the first color patch are included in a first range of the color values that may be taken by the plurality of color patches included in the second patch group, and the color values of the second color patch are included in a second range of the color values that may be taken by the plurality of color patches included in the third patch group. At least a part of the first range does not overlap with the second range, and at least a part of the second range does not overlap with the first range.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a color chart for color selection and a technique for generating a color chart for color selection.

A color selection color chart is used to select a color patch that matches a target color from a plurality of color patches. Patent Literature 1 discloses a color chart having 27 color patches printed on a medium. The 27 color patches are 3 × 3 color patches in which the a ^* value and b ^* value are respectively changed at the set color interval with the reference color as the center, and the L ^* value is more than the reference color by the set color interval. 3 * 3 color patches in which the a ^* value and b ^* value are respectively changed at the set color intervals with the reduced color as the center, and the L ^* value is increased by the set color interval from the reference color. The color patches are divided into 3 × 3 color patches in which the a ^* value and the b ^* value are each changed at a set color interval. Here, the L ^* value means the lightness in the CIE L ^* a ^* b ^* color space, and the a ^* value and the b ^* value mean the color coordinates in the CIE L ^* a ^* b ^* color space. CIE is an abbreviation of the International Commission on Illumination.

JP 2012-70298 A

  In the above-described technique, in order to accurately select a color patch of a target color, a user first prints a color chart on a medium with a wide color interval, and measures all 27 color patches. It is necessary to select a color patch that is close to the target color. Since the 27 color patches are arranged at wide color intervals, the color of the selected color patch does not always match the target color. Then, the user uses the selected color patch color as a new reference color, narrows the color interval, prints the color chart on the medium, measures all 27 color patches, and measures the color patch close to the target color. You need to repeat the task of selecting Such a repetitive operation is troublesome.

The present invention is a color selection color chart for selecting a color patch that matches a target color from a plurality of color patches,
The color chart for color selection includes a first patch group, a second patch group, and a third patch group,
The first patch group includes a plurality of color patches arranged at a first color difference interval including a first color patch and a second color patch,
The second patch group includes a plurality of color patches arranged at a second color difference interval narrower than the first color difference interval,
The third patch group includes a plurality of color patches arranged at the second color difference interval,
Assuming that the color values are coordinate values in the device independent color space,
The color value of the first color patch is included in a first range of possible color values of a plurality of color patches included in the second patch group,
The color value of the second color patch is included in a second range of possible color values of a plurality of color patches included in the third patch group,
At least a part of the first range does not overlap with the second range, and at least a part of the second range does not overlap with the first range.

Further, the present invention is a color selection color chart generation method for generating a color selection color chart for selecting a color patch that matches a target color from a plurality of color patches,
The color chart for color selection includes a first patch group, a second patch group, and a third patch group,
The color chart generation method for color selection,
A reference color value acquisition step of acquiring a reference color value;
A first patch group generating step of generating a first patch group including a plurality of color patches arranged at a first color difference interval including a first color patch and a second color patch based on the reference color value; ,
In a first range of color values that can be taken by a plurality of color patches included in the second patch group and in a first range including a color value corresponding to the first color patch, the first color difference interval is narrower. A second patch group generation step of generating a second patch group including a plurality of color patches arranged at a second color difference interval,
In a second range of color values that can be taken by a plurality of color patches included in the third patch group, and in a second range including color values corresponding to the second color patches, the color patches are arranged at the second color difference interval. A third patch group generating step of generating a third patch group including the plurality of color patches,
At least a part of the first range does not overlap with the second range, and at least a part of the second range does not overlap with the first range.

Further, the present invention has an aspect of a color selection color chart generation program that causes a computer to realize functions corresponding to the respective steps of the above-described color selection color chart generation method.
Further, the present invention has an aspect of a color selection color chart generation device including units ("parts") corresponding to the respective steps of the above-described color selection color chart generation method.

The figure which shows typically the example of the printed matter of the color chart for color selection. FIGS. 2A and 2B are diagrams schematically illustrating a relationship between color values of a first-layer color patch and a second-layer patch group. The figure which shows typically the example of the printed matter of the color chart for color selection. The figure which illustrates typically the relationship of the color value of the color patch of a 2nd hierarchy and the patch group of a 3rd hierarchy. The figure which shows another example of the printed matter of the color chart for color selection typically. FIG. 2 is a block diagram schematically illustrating a configuration example of a color chart generation device for color selection. The figure which shows typically the example of a structure of the color conversion table of a profile. 9 is a flowchart illustrating an example of a color selection color chart print control process. 9A to 9C are flowcharts illustrating an example of information acquisition processing. 9 is a flowchart illustrating an example of a color patch search process. The figure which shows typically the example of the color measurement guide screen of a 1st hierarchy. The figure which shows typically the example of the color measurement guide screen of a 2nd hierarchy. The figure which shows typically the example of the color measurement guide screen of a 3rd hierarchy. The figure which shows the example of a spot adjustment typically.

  Hereinafter, embodiments of the present invention will be described. Of course, the following embodiments are merely examples of the present invention, and not all of the features shown in the embodiments are essential for solving the invention.

(1) Outline of technology included in the present invention:
First, the outline of the technology included in the present invention will be described with reference to the examples shown in FIGS. It should be noted that the drawings of the present application are diagrams schematically showing examples, and the enlargement ratios in the respective directions shown in these drawings may be different, and the respective drawings may not match. Of course, each element of the present technology is not limited to a specific example indicated by a reference numeral. In the “Summary of Technology Included in the Present Invention”, the contents in parentheses mean supplementary explanation of the immediately preceding word.

[Aspect 1]
As illustrated in FIGS. 1, 2A, 2B, and the like, the color selection color chart CH0 according to one embodiment of the present technology is a color selection chart for selecting a color patch that matches a target color from a plurality of color patches P0. The color chart CH0 includes a first patch group G1, a second patch group G2, and a third patch group G3. The first patch group G1 includes a plurality of color patches including a first color patch P1 and a second color patch P2 and arranged at a first color difference interval ΔE1. The second patch group G2 includes a plurality of color patches arranged at a second color difference interval ΔE2 smaller than the first color difference interval ΔE1. The third patch group G3 includes a plurality of color patches arranged at the second color difference interval ΔE2. Here, it is assumed that the color values are coordinate values in the device-independent color space. The color values of the first color patch P1 are included in a first range 301 of color values that can be taken by a plurality of color patches included in the second patch group G2. The color values of the second color patch P2 are included in a second range 302 of color values that can be taken by a plurality of color patches included in the third patch group G3. At least a portion of the first range 301 does not overlap with the second range 302, and at least a portion of the second range 302 does not overlap with the first range 301.

  When the first color patch P1 is selected as being close to the target color from the first patch group G1 having the relatively wide first color difference interval ΔE1, the first range 301 including the color values of the first color patch P1 is relatively narrow. A color patch closer to the target color can be selected from the second patch group G2 with the second color difference interval ΔE2. When the second color patch P2 is selected as being close to the target color from the first patch group G1 having the relatively wide first color difference interval ΔE1, the comparison is performed in the second range 302 including the color values of the second color patch P2. A color patch closer to the target color can be selected from the third patch group G3 having the second narrower color difference interval ΔE2. The first patch group G1, the second patch group G2, and the third patch group G3 are included in the color selection color chart CH0. Here, since the plurality of distinguished patch groups are hierarchized, the number of color patches to be searched before searching for a color patch matching the target color by tracing the hierarchy of the patch groups can be reduced. Therefore, the present embodiment can provide a color selection color chart that reduces the work of searching for a color patch that matches the target color.

Here, the fact that the patch groups are distinguished in the color selection color chart means that there is a gap between one patch group and another patch group that is wider than the gap between the color patches in the patch group. This includes that the patch group is surrounded by a closed figure such as a frame or a closed curve.
The first patch group may include color patches other than the first color patch and the second color patch.
The color chart for color selection may include a distinct patch group other than the first patch group, the second patch group, and the third patch group.
For example, a CIE (International Commission on Illumination) L ^* a ^* b ^* color space can be applied to the device independent color space. The L ^* a ^* b ^* color space is a coordinate system defined in 1976 by the CIE (International Commission on Illumination). The color value in the L ^* a ^* b ^* color space is a coordinate value including an L ^* value that is lightness, and a ^* and b ^* values that are color coordinates.
The color difference between the color patches is compared by calculating according to the same calculation formula. To calculate the color difference, the color difference ΔE ₀₀ represented by the CIEDE2000 color difference formula, the color difference ΔE ^* ₉₄ represented by the CIE ₁₉₉₄ color difference formula, and the color difference defined as the Euclidean distance between coordinates in the CIE L ^* a ^* b ^* color space. ΔE ^* _ab , etc. can be used. The color difference ΔE ^* _ab may be described as ΔE76.
Note that the above remarks are also applied to the following aspects.

[Aspect 2]
As illustrated in FIGS. 1, 2A, 2B, etc., the first patch group G1, the second patch group G2, and the third patch group G3 are arranged in a first direction D1 and a second direction D2 that intersect each other. May be arranged. The color values of the plurality of color patches arranged in the first direction D1 may change in a first coordinate component in the device-independent color space. For example, FIGS. 1, 2A, and 2B show that the a ^* value changes as the first coordinate component. Further, the color values of the plurality of color patches arranged in the second direction D2 may have a second coordinate component in the device-independent color space that changes. For example, FIGS. 1, 2A, and 2B show that the b ^* value changes as the second coordinate component. According to this aspect, it is possible to provide a suitable color selection color chart that reduces the work of searching for a color patch that matches the target color.

[Aspect 3]
As illustrated in FIGS. 3 to 5, the color chart for color selection CH0 may further include a fourth patch group G4 and a fifth patch group G5. The fourth patch group G4 may include a plurality of color patches arranged at a third color difference interval ΔE3 smaller than the second color difference interval ΔE2. The fifth patch group G5 may include a plurality of color patches arranged at the third color difference interval ΔE3. Here, the second patch group G2 includes a third color patch P3 and a fourth color patch P4. The color value of the third color patch P3 may be included in a third range 303 of color values that can be taken by a plurality of color patches included in the fourth patch group G4. The color values of the fourth color patch P4 may be included in a fourth range 304 of color values that can be taken by a plurality of color patches included in the fifth patch group G5. At least a portion of the third range 303 may not overlap with the fourth range 304, and at least a portion of the fourth range 304 may not overlap with the third range 303.
According to this aspect, since a plurality of distinct patch groups are further hierarchized, it is possible to provide a color selection color chart that further reduces the operation of searching for a color patch that matches the target color.

[Aspect 4]
Further, as illustrated in FIG. 8 and the like, the color selection color chart generation method according to an aspect of the present technology includes a color selection color chart for selecting a color patch that matches a target color from a plurality of color patches P0. This is a color selection color chart generation method for generating a color chart CH0, comprising a reference color value acquisition step ST1, a first patch group generation step ST11, a second patch group generation step ST12, and a third patch group generation step ST13. Contains. Here, as exemplified in FIGS. 1, 2A, and 2B, the color selection color chart CH0 includes a first patch group G1, a second patch group G2, and a third patch group G2. The patch group G3 is included. In the reference color value obtaining step ST1, a reference color value (for example, a color center value shown in FIG. 8) is obtained. In the first patch group generation step ST11, based on the reference color value, a first patch group including a plurality of color patches including a first color patch P1 and a second color patch P2 and arranged at a first color difference interval ΔE1. One patch group G1 is generated. In the second patch group generation step ST12, a first range 301 of color values that can be taken by a plurality of color patches included in the second patch group G2, including a color value corresponding to the first color patch P1. In one range 301, a second patch group G2 including a plurality of color patches arranged at a second color difference interval ΔE2 smaller than the first color difference interval ΔE1 is generated. In the third patch group generation step ST13, a second range 302 of color values that can be taken by a plurality of color patches included in the third patch group G3, including a color value corresponding to the second color patch P2. In the two ranges 302, a third patch group G3 including a plurality of color patches arranged at the second color difference interval ΔE2 is generated. At least a portion of the first range 301 does not overlap with the second range 302, and at least a portion of the second range 302 does not overlap with the first range 301.

  In the generated color selection color chart CH0, when the first color patch P1 is selected as being close to the target color from the first patch group G1 having the relatively wide first color difference interval ΔE1, the color of the first color patch P1 In the first range 301 including the value, a color patch closer to the target color can be selected from the second patch group G2 of the second color difference interval ΔE2 which is relatively narrow. When the second color patch P2 is selected as being close to the target color from the first patch group G1 having the relatively wide first color difference interval ΔE1, the comparison is performed in the second range 302 including the color values of the second color patch P2. A color patch closer to the target color can be selected from the third patch group G3 having the second narrower color difference interval ΔE2. The first patch group G1, the second patch group G2, and the third patch group G3 are included in the color selection color chart CH0. Here, since the plurality of distinguished patch groups are hierarchized, the number of color patches to be searched before searching for a color patch matching the target color by tracing the hierarchy of the patch groups can be reduced. Therefore, the present embodiment can provide a color selection color chart generation method that reduces the work of searching for a color patch that matches the target color.

[Aspect 5]
As illustrated in FIGS. 1, 2A, 2B, etc., the first patch group G1, the second patch group G2, and the third patch group G3 included in the generated color selection color chart CH0 intersect each other. A plurality of color patches may be arranged in the first direction D1 and the second direction D2. The color values of the plurality of color patches arranged in the first direction D1 may change in a first coordinate component (for example, a ^* value in FIGS. 1, 2A, and 2B) in the device-independent color space. In the color values of the plurality of color patches arranged in the second direction D2, a second coordinate component (for example, b ^* value in FIGS. 1, 2A, and 2B) in the device independent color space may change. According to the present aspect, it is possible to provide a suitable color selection color chart generation method that reduces the work of searching for a color patch that matches the target color.

[Aspect 6]
As exemplified in FIG. 8 and the like, the method for generating a color chart for main color selection may further include a color difference receiving step ST2 for receiving the setting of the first color difference interval ΔE1. In this embodiment, the user can set the first color difference interval ΔE1 of the color patches in the first patch group G1, so that the convenience can be improved.

[Aspect 7]
As illustrated in FIG. 8 and the like, the main color selection color chart generation method includes setting the number of layers of a patch group including the first patch group G1, the second patch group G2, and the third patch group G3. It may further include a number-of-hierarchy receiving step ST3. Here, the second patch group G2 includes a third color patch P3 and a fourth color patch P4. When the number of layers is three or more, as illustrated in FIGS. 3 to 5, the color chart for color selection CH0 further includes a distinguished fourth patch group G4 and a distinguished fifth patch group G5. May be included. The method for generating a color chart for color selection may further include a fourth patch group generation step ST14 and a fifth patch group generation step ST15. In the fourth patch group generation step ST14, when the number of layers is three or more, the third range 303 of color values that can be taken by a plurality of color patches included in the fourth patch group G4, In a third range 303 including a color value corresponding to the color patch P3, a fourth patch group G4 including a plurality of color patches arranged at a third color difference interval ΔE3 smaller than the second color difference interval ΔE2 is generated. You may. In the fifth patch group generation step ST15, when the number of hierarchies is three or more, the fifth range 304 of color values that can be obtained by a plurality of color patches included in the fifth patch group G5 is the fourth range 304. In the fourth range 304 including the color value corresponding to the color patch P4, a fifth patch group G5 including a plurality of color patches arranged at the third color difference interval ΔE3 may be generated. At least a portion of the third range 303 may not overlap with the fourth range 304, and at least a portion of the fourth range 304 may not overlap with the third range 303.
According to this aspect, the number of layers of the patch group can be set by the user, so that the convenience can be improved.

[Aspect 8]
As illustrated in FIG. 6, the color selection color chart generation program PR0 according to an embodiment of the present technology includes a reference color value acquisition function FU1 corresponding to the reference color value acquisition step ST1, and a first patch group generation step ST11. The first patch group generation function FU11 corresponding to the first patch group generation function ST12, the second patch group generation function FU12 corresponding to the second patch group generation step ST12, and the third patch group generation function FU13 corresponding to the third patch group generation step ST13. (For example, the host device 100). This embodiment can provide a color selection color chart generation program that reduces the work of searching for a color patch that matches the target color. The main color selection color chart generation program PR0 includes a color difference reception function FU2 corresponding to the color difference reception step ST2, a layer number reception function FU3 corresponding to the layer number reception step ST3, and a fourth patch group corresponding to the fourth patch group generation step ST14. The generation function FU14 and the fifth patch group generation function FU15 corresponding to the fifth patch group generation step ST15 may be realized by a computer.

[Aspect 9]
As illustrated in FIG. 6, the color chart generation apparatus for color selection (for example, the host device 100) according to an embodiment of the present technology includes a reference color value acquisition unit U1 corresponding to a reference color value acquisition step ST1 and a first color value acquisition unit U1. A first patch group generation unit U11 corresponding to the patch group generation step ST11, a second patch group generation unit U12 corresponding to the second patch group generation step ST12, and a third patch group corresponding to the third patch group generation step ST13 Includes a generation unit U13. According to this aspect, it is possible to provide a color chart generation apparatus for color selection that reduces the work of searching for a color patch that matches the target color. The color selecting color chart generating apparatus includes a color difference receiving unit U2 corresponding to the color difference receiving step ST2, a layer number receiving unit U3 corresponding to the layer number receiving step ST3, and a fourth patch group generating step corresponding to the fourth patch group generating step ST14. A unit U14 and a fifth patch group generation unit U15 corresponding to the fifth patch group generation step ST15 may be included.

  Further, the present technology relates to a control method for a color chart generation device for color selection, a complex system including the color chart generation device for color selection, a control method for the complex system, a control program for the color chart generation device for color selection, and a control for the complex system. The present invention is applicable to a program, a color chart generation program for color selection, a computer-readable medium storing the control program, and the like. The device described above may be composed of a plurality of distributed parts.

In the following description, the L ^* a ^* b ^* color space and the description of "*" for representing L ^* , a ^* , and b ^* are omitted.

(2) Specific example of color chart for color selection:
FIG. 1 schematically illustrates a print of a color selection color chart CH0 formed on a print substrate ME1. Here, for the sake of simplicity, although not actually printed, a symbol P0 indicating a color patch, a symbol P1 indicating a first color patch, a symbol P2 indicating a second color patch, and a symbol G1 indicating a first patch group are not actually printed. , Symbol G2 indicating the second patch group, symbol G3 indicating the third patch group, “ΔE1 = 3”, “ΔE2 = 1”, a value of each color patch (upper row in the color patch), and each color patch (The lower row in the color patch). It is assumed that the first color difference interval ΔE1 and the second color difference interval ΔE2 shown in FIG. 1 are intervals of the color difference ΔE ^* _ab . The color value (L, a, b) of each color patch P0 is a theoretical value for forming each color patch P0, and is actually based on a CMYK value obtained by referring to a profile 500 shown in FIG. Each color patch P0 is formed on a printing substrate. Here, C means cyan, M means magenta, Y means yellow, and K means black. From the color chart CH0, the color value of each color patch P0 is obtained by measuring the color of each color patch P0 using the colorimeter 120 of FIG. 6 described later.

  The color chart CH0 for color selection of this specific example is characterized in that a plurality of patch groups are arranged hierarchically with distinction. As the hierarchy becomes deeper, the color difference intervals of the color patches of the patch group become narrower.

  For example, if there is no hierarchical patch group in the color chart for color selection, the user measures all the color patches on the color chart and calculates the color difference between all the colorimetric values and the target color. Above, it is necessary to specify the color patch having the minimum color difference. In order to accurately select a color patch of a target color, it is necessary to narrow a color difference interval between color patches arranged on a color selection color chart. As a result, the number of color patches included in the color selection color chart becomes enormous, the number of work steps increases, and the user cannot bear the trouble.

  In addition, as shown in JP-A-2012-70298, when a user specifies a reference color and a color interval each time to form a color chart having 27 color patches on a printing medium, the user first sets a color chart. It is necessary to print the color chart on the printing substrate with a wide interval. In order to accurately select the color patch of the target color, all the 27 color patches are measured, a color patch close to the target color is selected, and the color of the selected color patch is set as a new reference color. It is necessary to print a color chart on a printing substrate by reducing the color interval. Therefore, a color chart is generated by designating the reference color and the color interval each time, and the color patches close to the target color are selected by measuring all the 27 color patches, thereby repeating the operation. Such a repetitive operation is troublesome.

  In this specific example, by tracing the hierarchy of a plurality of distinct patch groups, the number of color patches to be searched before searching for a color patch that matches the target color can be reduced. Is reduced.

  The first-layer patch group A, which is an example of the first patch group G1, has an L-axis direction, an a-axis direction centering on (L, a, b) = (50, 0, -30) in the Lab color space. Also, 3 × 3 × 3 color patches arranged at the first color difference interval ΔE1 = 3 in the b-axis direction are included. In FIG. 1, a color chart CH1 including a 3 × 3 color patch of L = 50 and a second-layer patch group B1 to B9 of L = 50 in the first layer patch group A is printed on one sheet. It is shown that it is formed. The color chart including the first-layer patch group and the second-layer patch group other than L = 50 is hidden behind the color chart CH1. In the second layer patch group one step deeper than the patch group A, the second color difference interval ΔE2 = 1 smaller than the first color difference interval ΔE1 in the L-axis direction, the a-axis direction, and the b-axis direction. Contains multiple color patches. The plurality of first or second layer patch groups are distinguished by gaps CL1 and CL2 in the color selection color chart CH0 that are wider than the gaps between the color patches in the patch group. Here, the gap CL1 indicates a gap between layers, and the gap CL2 indicates a gap in the same layer.

The first layer patch group A and the second layer patch groups B1 to B9 included in the color chart CH1 have a first direction D1 in which the a value changes and a second direction D2 in which the b value changes. Multiple color patches are arranged. For all of the patch groups A, B1 to B9, the color values of the plurality of color patches arranged in the first direction D1 which is the horizontal direction in FIG. 1 are the a values which are examples of the first coordinate component in the Lab color space. Is changing. For all the patch groups A, B1 to B9, the color values of the plurality of color patches arranged in the second direction D2 which is the vertical direction in FIG. 1 are b values which are examples of the second coordinate component in the Lab color space. Is changing. In FIG. 1, the first direction D1 and the second direction D2 are orthogonal.
Of course, the coordinate components corresponding to the first direction D1 and the second direction D2 can be appropriately changed. For example, the b value may correspond to the first direction D1 and the L value may correspond to the second direction D2, or the L value may correspond to the first direction D1 and the a value may correspond to the second direction D2. Is also good.

  Each color patch included in the first layer patch group A is associated with one of the plurality of second layer patch groups. Referring to the color chart CH1 of L = 50 shown in FIG. 1, for example, the upper left color patch of the patch group A is associated with the second hierarchical patch group B1. Although not shown, the second layer patch group B1 also includes 3 × 3 color patches with L = 49 and color patches with L = 51. The color value (50, -3, -27) of the upper left color patch of the patch group A is a color value range 49 ≦ L ≦ of the 3 × 3 × 3 color patches included in the second hierarchical patch group B1. 51, −4 ≦ a ≦ −2, and −28 ≦ b ≦ −26. Similarly, the remaining color patches included in the patch group A are associated with one of the plurality of second hierarchical patch groups. For simplicity, the first layer patch group A includes the 3 × 3 color patches shown in FIG. 1, and the second layer patch groups B1 to B9 are associated with each color patch of the first layer patch group A. It is assumed that

  For convenience of describing the present technology, a certain color patch included in the first hierarchical patch group A is called a first color patch P1, and a color patch different from the first color patch P1 is called a second color patch P2. I will. That is, the first layer patch group A includes a plurality of color patches including the first color patch P1 and the second color patch P2 and arranged at the first color difference interval ΔE1. In the example shown in FIG. 1, the first color patch P1 and the second color patch P2 are located adjacent to each other, and the color patch having the color value (50, 0, -30) is the first color patch P1. The color patch having the value (50, 3, -30) is the second color patch P2. When the first color patch P1 and the second color patch P2 are adjacent to each other, the color difference between the first color patch P1 and the second color patch P2 is the first color difference interval ΔE1. The combination of the first color patch P1 and the second color patch P2 can be arbitrarily selected in the patch group A.

  Further, of the second hierarchical patch groups B1 to B9, a patch group associated with the first color patch P1 is referred to as a second patch group G2, and a patch group associated with the second color patch P2 is referred to as a third patch group. Let's call it group G3. That is, the second patch group G2 and the third patch group G3 include a plurality of color patches that are distinguished from each other and are arranged at the second color difference interval ΔE2 that is smaller than the first color difference interval ΔE1. In the example shown in FIG. 1, the second patch group G2 and the third patch group G3 are located adjacent to each other, the patch group B5 is the second patch group G2, and the patch group B6 is the third patch group G3. . Of course, the combination of the second patch group G2 and the third patch group G3 can be arbitrarily selected from the second hierarchical patch group according to the combination of the first color patch P1 and the second color patch P2.

  FIG. 2A schematically illustrates the relationship between the color values of the first-layer color patches P1 and P2 and the second-layer patch groups G2 and G3. Here, the horizontal axis is the a-axis direction which is the first direction D1, and the vertical axis is the b-axis direction which is the second direction D2. The color values of the first color patch P1 are included in the first range 301 of color values that can be taken by the plurality of color patches included in the second patch group G2, and the plurality of color patches included in the third patch group G3. Are not included in the second range 302 of possible color values. The color values of the second color patch P2 are included in the second range 302 of color values that can be taken by the plurality of color patches included in the third patch group G3, and the plurality of color patches included in the second patch group G2. Are not included in the first range 301 of possible color values. In the example shown in FIG. 2A, when the first color patch P1 and the second color patch P2 are located adjacent to each other in the patch group A, the first range 301 and the second range 302 have no overlapping portion. It has been shown.

However, in order to search for a color patch that matches the target color, if the color patches P1 and P2 are located adjacent to each other, as illustrated in FIG. 2B, the first range 301 of the second patch group G2 and the first There may be an overlapping range 310 that partially overlaps with the second range 302 of the three-patch group G3. FIG. 2B schematically illustrates the relationship between the color values of the color patches P1, P2 and the patch groups G2, G3 when the first range 301 and the second range 302 have an overlapping range 310. In FIG. 2B, three hatched color patches are also the three color patches having the largest a value of the second patch group G2, and the three color patches having the smallest a value of the third patch group G3. It is also a color patch. The range including these three color patches is the overlapping range 310. Part of the first range 301 does not overlap with the second range 302, and part of the second range 302 does not overlap with the first range 301.
Of course, the plurality of color patches in the overlapping range may be a plurality of color patches having the largest b value in the second patch group and the smallest b value in the third patch group, or the second patch group having the largest L value in the second patch group. In the three-patch group, a plurality of color patches having the smallest L value may be used. Even if the first color patch P1 and the second color patch P2 are in a positional relationship shifted in both the first direction D1 and the second direction D2, for example, in the second patch group, both the a value and the b value May be in the overlapping range in the third patch group in which both the a value and the b value are the smallest.

  2A and 2B, it can be said that at least a portion of the first range 301 does not overlap with the second range 302, and that at least a portion of the second range 302 does not overlap with the first range 301.

The color chart CH1 shown in FIG. 1 has a first-layer patch group A and a second-layer patch group B1 to B9 on the same substrate, but the second-layer patch group is a color selection color chart CH0. A third-level patch group that is one step deeper may be provided. FIG. 3 schematically illustrates a printed matter of a color selection color chart CH0 having a second layer patch group and a third layer patch group. Again, for the sake of simplicity, although not actually printed, a code P0 indicating a color patch, a code P3 indicating a third color patch, a code P4 indicating a fourth color patch, and a code G2 indicating a second patch group , A symbol G4 indicating the fourth patch group, a symbol G5 indicating the fifth patch group, “ΔE2 = 1”, “ΔE3 = 0.33”, a value of each color patch (upper row in the color patch), and The b value of the color patch (the lower part in the color patch) is shown. The second color difference interval ΔE2 and the third color difference interval ΔE3 shown in FIG. 3 are intervals of the color difference ΔE ^* _ab .

  The second layer patch group B5 shown in FIG. 3 is an example of the second patch group G2 associated with the first color patch P1. In the second hierarchical patch group B5, the second in the L-axis direction, the a-axis direction, and the b-axis direction around (L, a, b) = (50, 0, -30) in the Lab color space. 3 × 3 × 3 color patches arranged at a color difference interval ΔE2 = 1 are included. FIG. 3 shows a color chart CH2 including a 3 × 3 color patch of L = 50 and a third-layer patch group C1 to C9 of L = 50 in the second layer patch group B5 on one sheet of printing material. It is shown that it is formed. The color chart including the second-layer patch group and the third-layer patch group other than L = 50 is hidden behind the color chart CH2. In the third hierarchical patch group one step deeper than the patch group B5, the third color difference interval ΔE3 = 0.33, which is smaller than the second color difference interval ΔE2 in the L-axis direction, the a-axis direction, and the b-axis direction. A plurality of color patches are included. A plurality of patch groups on the second or third layer are distinguished by gaps CL1 and CL2 in the color selection color chart CH0 that are wider than the gaps between the color patches in the patch group.

  The second layer patch group B5 and the third layer patch groups C1 to C9 included in the color chart CH2 have a first direction D1 in which the a value changes and a second direction D2 in which the b value changes. Multiple color patches are arranged. For all of the patch groups B5, C1 to C9, the color values of the plurality of color patches arranged in the first direction D1, which is the horizontal direction in FIG. 3, are the a values, which are examples of the first coordinate component in the Lab color space. Is changing. For all of the patch groups B5, C1 to C9, the color values of the plurality of color patches arranged in the second direction D2 which is the vertical direction in FIG. 3 are b values which are examples of the second coordinate component in the Lab color space. Is changing. In FIG. 1, the first direction D1 and the second direction D2 are orthogonal. Of course, the coordinate components corresponding to the first direction D1 and the second direction D2 can be appropriately changed.

  Each color patch included in the second layer patch group B5 is associated with one of a plurality of third layer patch groups. For simplicity, the second layer patch group B5 includes the 3 × 3 color patches shown in FIG. 3, and the third layer patch groups C1 to C9 are associated with each color patch of the second layer patch group B5. It is assumed that

  For convenience of description of the present technology, a certain color patch included in the second hierarchical patch group B5 which is an example of the second patch group G2 is called a third color patch P3, and a color different from the third color patch P3. The patch will be referred to as a fourth color patch P4. That is, the second layer patch group B5 includes a plurality of color patches including the third color patch P3 and the fourth color patch P4 and arranged at the second color difference interval ΔE2. In the example shown in FIG. 3, the third color patch P3 and the fourth color patch P4 are located adjacent to each other, and the color patch having the color value (50, -1, -30) is the third color patch P3. The color patch having the color value (50, 0, -30) is the fourth color patch P4. When the third color patch P3 and the fourth color patch P4 are adjacent to each other, the color difference between the third color patch P3 and the fourth color patch P4 is the second color difference interval ΔE2. The combination of the third color patch P3 and the fourth color patch P4 can be arbitrarily selected from the second layer patch group B5.

  A patch group associated with the third color patch P3 among the third hierarchical patch groups C1 to C9 is referred to as a fourth patch group G4, and a patch group associated with the fourth color patch P4 is referred to as a fifth patch group. Let's call it group G5. That is, the fourth patch group G4 and the fifth patch group G5 include a plurality of color patches that are distinguished from each other and are arranged at the third color difference interval ΔE3 that is smaller than the second color difference interval ΔE2. In the example shown in FIG. 3, the fourth patch group G4 and the fifth patch group G5 are located adjacent to each other, the patch group C4 is the fourth patch group G4, and the patch group C5 is the fifth patch group G5. . Of course, the combination of the fourth patch group G4 and the fifth patch group G5 can be arbitrarily selected from the third hierarchical patch group according to the combination of the third color patch P3 and the fourth color patch P4.

  FIG. 4 schematically illustrates the relationship between the color values of the second-layer color patches P3 and P4 and the third-layer patch groups G4 and G5. Here, the horizontal axis is the a-axis direction which is the first direction D1, and the vertical axis is the b-axis direction which is the second direction D2. The color values of the third color patch P3 are included in the third range 303 of color values that can be taken by the plurality of color patches included in the fourth patch group G4, and the plurality of color patches included in the fifth patch group G5. Are not included in the fourth range 304 of possible color values. The color values of the fourth color patch P4 are included in the fourth range 304 of color values that can be taken by the plurality of color patches included in the fifth patch group G5, and the plurality of color patches included in the fourth patch group G4. Are not included in the third range 303 of possible color values. In the example shown in FIG. 4, when the third color patch P3 and the fourth color patch P4 are located adjacent to each other in the second layer patch group B5, the third range 303 and the fourth range 304 overlap. No parts are shown.

  Although not shown, when the color patches P3 and P4 are located adjacent to each other, the third range 303 of the fourth patch group G4 and the fourth range 304 of the fifth patch group G5 partially overlap. There may be a range. Even if the third color patch P3 and the fourth color patch P4 are in a positional relationship shifted in both the first direction D1 and the second direction D2, for example, in the fourth patch group, both the a value and the b value May be the largest in the fifth patch group, and the color patch in which both the a value and the b value are the smallest may be in the overlapping range.

  From the above, it can be said that at least part of the third range 303 does not overlap with the fourth range 304, and that at least part of the fourth range 304 does not overlap with the third range 303.

  Although not shown, the color chart CH0 for color selection may include a patch group of a deeper layer, such as a fourth layer patch group one step deeper than the third layer patch group. Assuming that the patch group of the n-th layer has a plurality of color patches arranged at the color difference interval ΔEn, the color difference interval ΔE (n + 1) of the color patches included in the patch group of the (n + 1) th layer is larger than the color difference interval ΔEn. narrow. Here, n is an integer of 1 or more.

Further, as illustrated in FIG. 5, the first-layer patch group A, the second-layer patch groups B1 to B4, and the third-layer patch groups C1 to C16 may be formed on one printing material. FIG. 5 schematically illustrates a printed matter of a color selection color chart CH0 having a first layer patch group, a second layer patch group, and a third layer patch group. Again, for the sake of simplicity, although not actually printed, a code P0 indicating a color patch, a code P1 indicating a first color patch, a code P2 indicating a second color patch, and a code P3 indicating a third color patch A symbol P4 indicating a fourth patch group, a symbol G1 indicating a first patch group, a symbol G2 indicating a second patch group, a symbol G3 indicating a third patch group, a symbol G4 indicating a fourth patch group, and a fifth patch group. G5, “ΔE1 = 4”, “ΔE2 = 2”, “ΔE3 = 1”, the a value of each color patch (the upper part in the color patch), and the b value of each color patch (the (Lower row). It is assumed that the first color difference interval ΔE1, the second color difference interval ΔE2, and the third color difference interval ΔE3 shown in FIG. 5 are intervals of the color difference ΔE ^* _ab .

  In FIG. 5, a first-layer patch group A, which is an example of the first patch group G1, includes (L, a, b) = (50, 0, −30) in the L-axis direction, the a-axis direction, In addition, it is assumed that 2 × 2 × 2 color patches arranged at the first color difference interval ΔE1 = 4 in the b-axis direction are included. FIG. 5 shows a 2 × 2 color patch of L = 48, a second-layer patch group B1 to B4 of L = 48, and a third-layer patch group C1 of L = 48 in the first-layer patch group A. It is shown that the color chart CH3 including C16 is formed on one printing material. The color chart including the first layer patch group, the second layer patch group, and the third layer patch group other than L = 48 is hidden behind the color chart CH3. Each of the second-layer patch groups B1 to B4 has a second color difference in the L-axis direction, the a-axis direction, and the b-axis direction around the color value of the color patch associated with the first-layer patch group A. It is assumed that 2 × 2 × 2 color patches arranged at an interval ΔE2 = 2 are included. Each of the third-layer patch groups C1 to C16 has a third value in the L-axis direction, the a-axis direction, and the b-axis direction centering on the color values of the color patches associated with the second-layer patch groups B1 to B4. It is assumed that 2 × 2 × 2 color patches arranged at the color difference interval ΔE3 = 1 are included.

  Here, in the first layer patch group A, the first color patch P1 is associated with the second layer patch group B1 as an example of the second patch group G2, and the second color patch P2 is an example of the third patch group G3. Is associated with the second hierarchical patch group B2. The color values of the first color patch P1 are included in a first range of color values that can be taken by a plurality of color patches included in the second layer patch group B1, and the color values of the second color patch P2 are included in the second layer patch group B2. Are included in a second range of possible color values of a plurality of color patches included in. The first range and the second range do not overlap.

  In the second-layer patch group B1, the third color patch P3 is associated with the third-layer patch group C1 as an example of the fourth patch group G4, and the fourth color patch P4 is as an example of the fifth patch group G5. It is assumed that it is associated with the third hierarchical patch group C2. The color values of the third color patch P3 are included in a third range of color values that can be taken by a plurality of color patches included in the third layer patch group C1, and the color values of the fourth color patch P4 are included in the third layer patch group C2. Are included in the fourth range of possible color values of the plurality of color patches included in. The third and fourth ranges do not overlap.

(3) Specific example of the configuration of the color chart generation device for color selection:
FIG. 6 schematically shows a host device 100 together with peripheral devices as a configuration example of a color chart generation device for color selection. The system shown in FIG. 6 includes a display device 130, a colorimetric device 120, and an inkjet printer 200 in addition to the host device 100. The host device 100 is connected to a CPU 111, a ROM 112, a RAM 113, a storage device 114, an input device 115, a communication I / F 118, a colorimetric device I / F 119, and the like so that information can be input and output to and from each other. Here, CPU is an abbreviation for Central Processing Unit, ROM is an abbreviation for Read Only Memory, RAM is an abbreviation for Random Access Memory, and I / F is an abbreviation for interface. The ROM 112, the RAM 113, and the storage device 114 are memories, and at least the ROM 112 and the RAM 113 are semiconductor memories. The display device 130 displays a screen corresponding to the display data based on the display data from the host device 100. As the display device 130, a liquid crystal display panel or the like can be used.

  The storage device 114 stores an OS (not shown), a color chart generation program PR0 for color selection, a profile 500, and the like. These are read out to the RAM 113 as appropriate, and are used in the process of generating a color chart for color selection. Here, the OS is an abbreviation of an operating system. As the storage device 114, a nonvolatile semiconductor memory such as a flash memory, a magnetic storage device such as a hard disk, or the like can be used.

As the input device 115, a pointing device, a hard key including a keyboard, a touch panel attached to a surface of a display panel, or the like can be used. The communication I / F 118 is connected to the communication I / F 210 of the printer 200, and inputs and outputs information such as print data to the printer 200. The colorimetric device I / F 119 is connected to the colorimetric device 120 and acquires colorimetric data including colorimetric values from the colorimetric device 120. USB, short-range wireless communication standards, and the like can be used as the standards of the I / Fs 118, 119, and 210. Here, USB is an abbreviation for Universal Serial Bus. The communication of the communication I / Fs 118, 119, and 210 may be wired, wireless, or network communication such as a LAN or the Internet. Here, LAN is an abbreviation for Local Area Network.
The colorimetric device 120 can measure the color of each color patch formed on the printing medium ME1, which is an example of a medium on which a color chart is formed, and can output a colorimetric value. Patches are also called color patches. The colorimetric values are, for example, values representing the lightness L and the chromaticity coordinates a and b in the Lab color space. The colorimetric device 120 of this specific example is a manual type, and when a user applies a sensor unit to a color patch, the color patch is measured and the colorimetric data including the corresponding colorimetric value is output to the host device 100. I do. The host device 100 acquires colorimetric data from the colorimetric device 120 and performs various processes.

  The color selection color chart generation program PR0 illustrated in FIG. 6 causes the host device 100 to realize the reference color value acquisition function FU1, the color difference reception function FU2, the number of layers reception function FU3, and the color chart generation function FU10. The color chart generation function FU10 includes a first patch group generation function FU11, a second patch group generation function FU12, a third patch group generation function FU13, a fourth patch group generation function FU14, and a fifth patch group generation function FU15. In.

  The CPU 111 of the host device 100 performs various processes by appropriately reading information stored in the storage device 114 into the RAM 113 and executing the read program. The CPU 111 executes the processing corresponding to the functions FU1, FU2, FU3, and FU10 by executing the color selection color chart generation program PR0 read into the RAM 113. The color chart generation program for color selection PR0 causes the host device 100, which is a computer, to function as a reference color value acquisition unit U1, a color difference reception unit U2, a layer number reception unit U3, and a color chart generation unit U10. The color chart generator U10 includes a first patch group generator U11, a second patch group generator U12, a third patch group generator U13, a fourth patch group generator U14, and a fifth patch group generator U15. In. Further, the host device 100 executing the color selection color chart generation program PR0 and the printer 200 execute the reference color value acquisition step ST1, the color difference reception step ST2, the number of layers reception step ST3, and the color chart generation step ST10. I do. The color chart generation step ST10 includes a first patch group generation step ST11, a second patch group generation step ST12, a third patch group generation step ST13, a fourth patch group generation step ST14, and a fifth patch group generation step ST15. In. The computer-readable medium that stores the color selection color chart generation program PR0 that causes the computer to realize the functions FU1, FU2, FU3, and FU10 described above is not limited to the storage device inside the host device, and is not limited to the storage device inside the host device. It may be a recording medium.

  Note that the host device 100 includes a computer such as a personal computer including a tablet terminal. For example, when the main body of a desktop personal computer is applied to the host device 100, usually, the display device 130, the colorimetric device 120, and the printer 200 are connected to the main body. When a computer integrated with a display device such as a notebook personal computer is applied to the host device 100, the colorimetric device 120 and the printer 200 are usually connected to the computer. The display device integrated type host device still outputs display data to the internal display device. The host device 100 may include all the components 111 to 119 in one housing, or may include a plurality of devices communicably divided. Furthermore, the present technology can be implemented even when at least a part of the display device 130, the colorimetric device 120, and the printer 200 are in the host device 100.

  The printer 200 illustrated in FIG. 6 is an inkjet printer that discharges at least C ink, M ink, Y ink, and K ink as recording materials from the recording head 220 to form an output image IM0 corresponding to print data. Shall be. The recording head 220 is supplied with inks of C, M, Y, and K from the ink cartridges Cc, Cm, Cy, and Ck, respectively, and ink droplets 280 of C, M, Y, and K from the nozzles Nc, Nm, Ny, and Nk, respectively. Inject. When the ink droplet 280 lands on the printing medium ME1, ink dots are formed on the printing medium ME1. As a result, a printed material having the output image IM0 on the printed material ME1 is obtained. When a profile representing the color reproduction characteristics of the printer 200 is created, a color chart having a patch corresponding to the color of each grid point may be formed on the printing medium ME1 by the printer 200. A color conversion table having the colorimetric values of each patch is used for creating a profile as an A2B table.

(4) Specific example of profile:
FIG. 7 schematically illustrates the structure of the profile 500. As the profile 500, for example, a data format of an ICC profile can be used. Here, ICC is an abbreviation for International Color Consortium. The profile 500 shown in FIG. 7 is data representing the correspondence between the coordinate values of the CMYK color space CS1 and the coordinate values of the Lab color space CS2 depending on the device, and represents the characteristics of the output color of the device. The devices include an input device such as an offset printing machine, a gravure printing machine, a flexographic printing machine, and a display device, and an output device such as an inkjet printer 200.

  The profile 500 includes an A2B table 501 which is a color conversion table for converting coordinate values in the CMYK color space CS1 into coordinate values in the Lab color space CS2, and converts coordinate values in the Lab color space CS2 into coordinate values in the CMYK color space CS1. B2A table 502, which is a color conversion table to be converted.

The A2B table 501 includes CMYK values (C _i , M _i , Y _i , K _i ), which are coordinate values in the CMYK color space CS1, and Lab values (L _i , a _i , b) which are coordinate values in the Lab color space CS2. _i ) and the data defining the correspondence between them. Normally, the grid points GD1 of the A2B table 501 are arranged in the CMYK color space at substantially equal intervals in the C-axis direction, the M-axis direction, the Y-axis direction, and the K-axis direction. Here, the variable i is a variable for identifying the grid point GD1 set in the CMYK color space CS1. When the CMYK color space CS1 is a color space that depends on the printer 200, the CMYK values (C _i , M _i , Y _i , K _i ) are coordinate values according to the amount of ink used by the printer 200.

The B2A table 502 shows the correspondence between the Lab values (L _j , a _j , b _j ) of the Lab color space CS2 and the CMYK values (C _j , M _j , Y _j , K _j ) of the CMYK color space CS1. This is the specified data. Normally, the grid points GD2 of the B2A table 502 are arranged in the Lab color space at substantially equal intervals in the L-axis direction, the a-axis direction, and the b-axis direction. Here, the variable j is a variable for identifying the grid point GD2 set in the Lab color space.

Note that the color conversion table included in the profile 500 is not limited to a single conversion table, and may include a plurality of conversion tables such as a combination of a one-dimensional conversion table, a three- or four-dimensional conversion table, and a one-dimensional conversion table. May be combined. Therefore, the A2B table 501 and the B2A table 502 shown in FIG. 7 may directly indicate a three- or four-dimensional conversion table included in the profile 500, or indicate a state in which a plurality of conversion tables included in the profile 500 are combined. In some cases.
A grid point means a virtual point arranged in the input-side color space, and coordinate values on the output side corresponding to the positions of the grid points in the input-side color space are stored in the grid points. I'm supposed to. The present technology includes not only that a plurality of grid points are uniformly arranged in the input side color space, but also that a plurality of grid points are unevenly arranged in the input side color space.

  When the printer 200 uses a total of four inks of CMYK, the CMYK values are transmitted to the printer 200 as they are or after being converted into data for printing and used for printing. When the printer 200 uses five or more colors of ink, the CMYK values are converted into data representing the amount of ink of five or more colors by the color separation table, transmitted to the printer 200, and used for printing. The colors of the five or more inks include, in addition to CMYK, Lc having a lower density than C, ie, light cyan, Lm having a lower density than M, ie, light magenta, Dy having a higher density than Y, ie, dark yellow, and lower than K. Some or all of the density Lk, that is, light black, etc. are exemplified. The host device 100 or the printer 200 can reproduce an image on a printed material by separating the CMYK values into dark and light colors according to the color separation table. For example, when the printer 200 uses inks of a total of six colors of C, M, Y, K, Lc, and Lm, the coordinates of the C, M, Y, K, Lc, and Lm are used as the coordinate values in the CMYK color space. May be used as the color separation table associated with the gradation value representing

(5) Specific example of color chart print control processing for color selection:
FIG. 8 illustrates a color chart print control process for color selection performed by the host device 100 shown in FIG. This processing is based on the premise that a patch group is formed up to the fourth hierarchy. Note that the host device 100 executes a plurality of processes in parallel by multitasking. Here, step S105 corresponds to the reference color value acquisition step ST1, the reference color value acquisition function FU1, and the reference color value acquisition unit U1. Step S112 corresponds to the color difference receiving step ST2, the color difference receiving function FU2, and the color difference receiving unit U2. Step S118 corresponds to the number-of-layers receiving step ST3, the number-of-layers receiving function FU3, and the number-of-layers receiving unit U3. Steps S120 to S180 correspond to the color chart generation step ST10, the color chart generation function FU10, and the color chart generation unit U10. Step S120 corresponds to the first patch group generation step ST11, the first patch group generation function FU11, and the first patch group generation unit U11. Step S130 includes a second patch group generation step ST12, a third patch group generation step ST13, a second patch group generation function FU12, a third patch group generation function FU13, a second patch group generation unit U12, and a third patch group. It corresponds to the generation unit U13. Step S150 includes a fourth patch group generation step ST14, a fifth patch group generation step ST15, a fourth patch group generation function FU14, a fifth patch group generation function FU15, a fourth patch group generation unit U14, and a fifth patch group. This corresponds to the generation unit U15.
Hereinafter, the description of “step” is omitted.

When the color chart print control process for color selection is started, the host device 100 determines a color difference equation for setting the color difference interval of the patch group in S100. For example, the host device 100 causes the display device 130 to display a selection field including the color difference ΔE ₀₀ , the color difference ΔE ^* ₉₄ , and the color difference ΔE ^* _ab, and accepts any one of the color differences from the selection field by the input device 115. It can be. If the color difference ΔE ₀₀ have been accepted is determined the use of CIEDE2000 color difference formula, if the color difference ΔE ^* ₉₄ has been accepted CIE1994_nenshokusashikinoshiyogaketteisare, if the color difference ΔE ^* _ab is accepted Lab color The use of a color difference equation, defined as the Euclidean distance between coordinates in space, will be determined.

  After determining the color difference formula to be used, the host device 100 acquires a color center value (L0, a0, b0) which is an example of the reference color value in S105. The color center value (L0, a0, b0) is a color value representing the center of the color values that can be taken by a plurality of color patches included in the patch group A of the first hierarchy shown in FIG. The host device 100 displays, for example, a color center value input field 710 as shown in FIG. 8 on the display device 130, and inputs the L value, a value, and b value in the color center value input field 710. What is necessary is just to perform the process accepted by the input device 115. The received color value becomes the color center value (L0, a0, b0).

After acquiring the color center value, in S110, the host device 100 acquires various values for generating data representing the patch group. The information acquisition process of S110 includes the process of S112 for acquiring the first color difference interval ΔE1 in the first layer patch group A, the process of S114 for acquiring the colorimetric number Ni for each layer, and the color difference interval for the last layer patch group. The processing of S116 for acquiring the threshold Te and the processing of S118 for acquiring the hierarchy level Le indicating the number of layers of the patch group are included. Here, the variable i in the colorimetric number Ni is a variable for identifying the hierarchy of the patch group. Hakairosu Ni, when the number of axial patches contained in the differentiated patch group in the color selection for color chart CH0 and Zi, the Zi ^3. The colorimetric number Ni is preferably an odd cube such as 3 × 3 × 3 = 27, 5 × 5 × 5 = 125, but an even number such as 2 × 2 × 2 = 8, 4 × 4 × 4 = 64. It may be a cube. The first hierarchical color difference interval ΔE1, the number of colorimetric measurements Ni for each hierarchical level, the final color difference threshold Te, and the hierarchical level Le may be determined by default or may be specified by the user.

  Since the first hierarchical color difference interval ΔE1, the colorimetric number per hierarchy Ni, the final color difference threshold Te, and the hierarchical level Le are closely related, various processing orders can be considered for the processing of S112 to S118.

  In FIG. 9A, in S110, after performing the processing in the order of S112, S114, and S116, the hierarchical level Le is calculated and obtained based on the first hierarchical color difference interval ΔE1, the colorimetric number Ni for each layer, and the final color difference threshold Te. An example in which the process of S118 is performed is shown. In S112, for example, the host device 100 may cause the display device 130 to display an input field for the first-tier color difference interval ΔE1, and accept the input of the first-tier color difference interval ΔE1 for this input field by the input device 115. . Thus, the setting of the first-tier color difference interval ΔE1 is accepted. Further, in S114, for example, the host device 100 causes the display device 130 to display an input field of the colorimetric number Ni for each layer, and performs a process of receiving the input of the colorimetric number Ni for each layer in the input field by the input device 115. Just do it. As a result, the setting of the number of colors Ni for each layer is accepted. Furthermore, in S116, the host device 100 may display an input field for the final color difference threshold Te on the display device 130, for example, and perform processing for accepting the input of the final color difference threshold Te in this input field by the input device 115. Thereby, the setting of the final color difference threshold Te is accepted.

  For example, it is assumed that the first-layer color difference interval ΔE1 is 5, the colorimetric number Ni of all layers is 125, that is, Zi = 5, and the final color difference threshold Te is 1. In this case, since ΔE1 / Zi = 5/5 = 1, the second color difference interval ΔE2 in the second hierarchical patch group is 1. That is, since the second color difference interval ΔE2 is equal to or less than the final color difference threshold Te, the hierarchical level Le is calculated as 2.

  FIG. 9B shows that, in S110, the processing is performed in the order of S114, S116, and S118, and then the first layer color difference interval ΔE1 is calculated and obtained based on the number of colors per layer Ni, the final color difference threshold Te, and the layer level Le. The example which performs the process of S112 is shown. The host device 100 may perform the processing described with reference to FIG. 9A in S114 and S116, for example. Further, in S118, for example, the host device 100 may display the input field of the hierarchical level Le on the display device 130, and perform the process of receiving the input of the hierarchical level Le in the input field by the input device 115. Thereby, the setting of the hierarchy level Le is accepted.

  For example, it is assumed that the colorimetric number Ni of all layers is 27, that is, Zi = 3, the final color difference threshold Te is 0.5, and the layer level Le is 3. In this case, the third color difference interval ΔE3 in the third hierarchical patch group is Te = 0.5, and the second color difference interval ΔE2 in the second hierarchical patch group is 0.5 × ΔE3 / Zi = 1.5. Therefore, the first hierarchical color difference interval ΔE1 is calculated as 1.5 × ΔE2 / Zi = 4.5.

  In FIG. 9C, in S110, after performing the processing in the order of S112, S114, and S118, the final color difference threshold Te is calculated and acquired based on the first layer color difference interval ΔE1, the number of colorimetric measurements Ni per layer, and the layer level Le. An example in which the processing of S116 is performed is shown. In S112, S114, and S118, the host device 100 may perform, for example, the processing described with reference to FIGS. 9A and 9B.

  For example, it is assumed that the first-layer color difference interval ΔE1 is 5, the colorimetric numbers Ni of all layers are 125, that is, Zi = 5, and the layer level Le is 3. In this case, since ΔE1 / Zi = 5/5 = 1, the second color difference interval ΔE2 in the second hierarchical patch group is 1. Next, since ΔE2 / Zi = 1/5 = 0.2, the third color difference interval ΔE3 in the third hierarchical patch group is 0.2. That is, the final color difference threshold Te is calculated to be 0.2.

  Also, the first-layer color difference interval ΔE1 is 1.5, the first-layer colorimetric number N1 is 125, ie, Z1 = 5, the second-layer colorimetric number N2 is 27, ie, Z2 = 3, and the It is assumed that the level Le is 2. In this case, since ΔE1 / Z2 = 1.5 / 3 = 0.5, the second color difference interval ΔE2 in the second hierarchical patch group is 0.5. That is, the final color difference threshold Te is calculated as 0.5.

Returning to FIG. 8, the description will be continued. After the processing in S110, the host device 100 determines in S120 based on the color center value (L0, a0, b0), the first color difference interval ΔE1 and the number N1 of colorimetry in the first hierarchical patch group, and the like. The first-layer patch data for forming the first-layer patch group A as indicated by is generated. The first layer patch data includes a first patch group G1 including a plurality of color patches arranged at a first color difference interval ΔE1 including a first color patch P1 and a second color patch P2. Group data. The host device 100 has, for example, the number of color patches Z1 = (N1) ^1/3 in the L-axis direction, the a-axis direction, and the b-axis direction around the color center value (L0, a0, b0). The first patch group data may be generated so as to be arranged at the first color difference interval ΔE1.

For example, when ΔE ^* _ab is used for calculating the color difference, the range of the color values (L, a, b) that can be taken by a plurality of color patches included in the first-layer patch group A is as follows.
L0−ΔE1 × (Z1-1) / 2 ≦ L ≦ L0 + ΔE1 × (Z1-1) / 2 (1)
a0−ΔE1 × (Z1-1) / 2 ≦ a ≦ a0 + ΔE1 × (Z1-1) / 2 (2)
b0−ΔE1 × (Z1-1) / 2 ≦ b ≦ b0 + ΔE1 × (Z1-1) / 2 (3)
Here, the color values of the color patches included in the first hierarchical patch group A are represented by (L1, a1, b1).

After the generation of the first patch group data, the host device 100 determines in S130 the second layer patch group associated with each color patch included in the first layer patch group A, The second layer patch data is generated based on the color values (L1, a1, b1), the second color difference interval ΔE2 in the second layer patch group, and the colorimetric number N2. The second layer patch data includes the third color patch P3 and the fourth color patch P4 and is arranged at the second color difference interval ΔE2 narrower than the first color difference interval ΔE1, as shown in FIGS. For generating a second layer patch group including a plurality of obtained color patches. The second layer patch data includes second patch group data for generating the second patch group G2 and third patch group data for generating the third patch group G3. Here, the second patch group G2 includes a plurality of color patches arranged at the second color difference interval ΔE2 in the first range 301 including the color values corresponding to the first color patch P1. The third patch group G3 includes a plurality of color patches arranged at the second color difference interval ΔE2 in the second range 302 including the color value corresponding to the second color patch P2. The host device 100 may, for example, center on the color values (L1, a1, b1) of the color patches included in the patch group A in the L-axis direction, the a-axis direction, and the b-axis direction in the number of axial patches Z2 = (N2 The second layer patch data including the second patch group data and the third patch group data may be generated so that ^1/3 of the color patches are arranged at the second color difference interval ΔE2.

For example, when ΔE ^* _ab is used for calculating the color difference, the range of color values (L, a, b) that can be obtained by a plurality of color patches included in each second-layer patch group is as follows.
L1−ΔE2 × (Z2-1) / 2 ≦ L ≦ L1 + ΔE2 × (Z2-1) / 2 (4)
a1−ΔE2 × (Z2-1) / 2 ≦ a ≦ a1 + ΔE2 × (Z2-1) / 2 (5)
b1−ΔE2 × (Z2-1) / 2 ≦ b ≦ b1 + ΔE2 × (Z2-1) / 2 (6)
Here, the color values of the color patches included in the second layer patch group are represented by (L2, a2, b2).

  After generating the second patch group data, in S140, the host device 100 branches the processing depending on whether or not the hierarchical level Le is 3 or more. If Le <3, there is no need to generate a patch group for the third and subsequent layers, so the host device 100 advances the processing to S180.

If the hierarchical level Le is 3 or more, the host device 100 determines in S150 that the color included in the second layer patch group is the third layer patch group associated with each color patch included in the second layer patch group. The third layer patch data is generated based on the color values (L2, a2, b2) of the patch, the third color difference interval ΔE3 and the number of colorimetry N3 in the third layer patch group. The third layer patch data generates a third layer patch group including a plurality of color patches arranged at a third color difference interval ΔE3 smaller than the second color difference interval ΔE2 as shown in FIGS. Data for The third layer patch data includes fourth patch group data for generating the fourth patch group G4 and fifth patch group data for generating the fifth patch group G5. Here, the fourth patch group G4 includes a plurality of color patches arranged at the third color difference interval ΔE3 in the third range 303 including the color value corresponding to the third color patch P3. The fifth patch group G5 includes a plurality of color patches arranged at the third color difference interval ΔE3 in the fourth range 304 including the color values corresponding to the fourth color patch P4. The host device 100, for example, centers on the color values (L2, a2, b2) of the color patches included in the second-level patch group, and proceeds along the L-axis direction, the a-axis direction, and the b-axis direction in the number Z3 = (N3) Third-layer patch data including the fourth patch group data and the fifth patch group data may be generated such that ^1/3 of the color patches are arranged at the third color difference interval ΔE3.

For example, when ΔE ^* _ab is used for calculating the color difference, the range of color values (L, a, b) that can be obtained by a plurality of color patches included in each third-layer patch group is as follows.
L2-ΔE3 × (Z3-1) / 2 ≦ L ≦ L2 + ΔE3 × (Z3-1) / 2 (7)
a2-ΔE3 × (Z3-1) / 2 ≦ a ≦ a2 + ΔE3 × (Z3-1) / 2 (8)
b2-ΔE3 × (Z3-1) / 2 ≦ b ≦ b2 + ΔE3 × (Z3-1) / 2 (9)
Here, the color values of the color patches included in the third layer patch group are represented by (L3, a3, b3).

  After the generation of the third patch group data, the host device 100 branches the process in S160 according to whether the hierarchical level Le is 4 or not. If Le = 4, the host device 100 proceeds with the process to S180 because there is no need to generate the fourth layer patch group.

If the hierarchical level Le is 4, the host device 100 determines in S170 that the fourth level patch group associated with each color patch included in the third level patch group includes a color patch included in the third level patch group. And the fourth layer patch data for forming the fourth layer patch group based on the color values (L3, a3, b3) of the third layer, the fourth color difference interval ΔE4 and the number of colorimetry N4 in the fourth layer patch group. Generate. The fourth layer patch data is data for generating a fourth layer patch group including a plurality of color patches arranged at a fourth color difference interval ΔE4 smaller than the third color difference interval ΔE3. The host device 100 may, for example, center on the color values (L3, a3, b3) of the color patches included in the third-layer patch group and change the number of axial patches Z4 in the L-axis direction, the a-axis direction, and the b-axis direction = (N4) The fourth hierarchical patch data may be generated such that ^1/3 of the color patches are arranged at the fourth color difference interval ΔE4.

For example, when ΔE ^* _ab is used for calculating the color difference, the range of color values (L, a, b) that can be obtained by a plurality of color patches included in each fourth-layer patch group is as follows.
L3-ΔE4 × (Z4-1) / 2 ≦ L ≦ L3 + ΔE4 × (Z4-1) / 2 (10)
a3−ΔE4 × (Z4-1) / 2 ≦ a ≦ a3 + ΔE4 × (Z4-1) / 2 (11)
b3−ΔE4 × (Z4-1) / 2 ≦ b ≦ b3 + ΔE4 × (Z4-1) / 2 (12)
Thereafter, the host device 100 advances the processing to S180.

  In S180, based on the patch data of each layer, the host device 100 generates a print image in which identification information, for example, A, B1 to B9, and C1 to C9 shown in FIGS. The print data is generated, and the print data is transmitted to the printer 200, and the color chart print control processing for color selection ends. The patch data of each layer includes a first layer patch data, a second layer patch data, a third layer patch data when the layer level Le is 3 or more, and a fourth layer patch data when the layer level Le is 4 Is included. The patch data of each layer is represented by Lab values. Therefore, the host device 100 refers to the B2A table 502 of the profile 500 shown in FIG. 7, converts the Lab value representing the patch data of each layer into a CMYK value, and, based on the CMYK value, each patch group and identification information. May be generated and transmitted to the printer 200.

The printer 200, which has received the print data from the host device 100, forms a group of patches classified into each layer on the printing medium ME1 together with the identification information based on the print data.
Here, based on the data corresponding to the first layer patch data in the print data, the printer 200 sets the L-axis direction, the a-axis direction, and the b-axis direction around the color center value (L0, a0, b0). A first-level patch group A (see FIG. 1 and the like) in which the number of color patches of the axial direction Z1 = (N1) ^1/3 is arranged at the first color difference interval ΔE1.
In addition, the printer 200, based on the data corresponding to the second-level patch data of the print data, centers on the color values (L1, a1, b1) of the color patches included in the patch group A and the L-axis direction and a In the axial direction and the b-axis direction, the number of patches in the axial direction Z2 = (N2) ^1/3 color patches are generated by distinguishing each second layer patch group (see FIG. 1 and the like) in which the second color difference interval ΔE2 is arranged. . According to the above inequalities (4) to (6), there is no overlapping part in the range of the color values that can be taken by the plurality of color patches included in each second-layer patch group.

When the layer level Le is 3 or more, the printer 200 determines the color values (L2, a2, b2) of the color patches included in the second layer patch group based on the print data corresponding to the third layer patch data. ), The third-layer patch group in which the number of color patches Z3 = (N3) ^1/3 in the L-axis direction, the a-axis direction, and the b-axis direction is arranged at the third color difference interval ΔE3 ( (See FIG. 3 etc.). According to the inequalities (7) to (9) described above, there is no overlapping part in the range of the color values that can be taken by the plurality of color patches included in each third-layer patch group.
When the hierarchical level Le is 4, the printer 200 determines the color value (L3, a3, b3) of the color patch included in the third hierarchical patch group based on the print data corresponding to the fourth hierarchical patch data. , The fourth-layer patch group in which the number of color patches Z4 = (N4) ^1/3 in the L-axis direction, the a-axis direction, and the b-axis direction is arranged at a fourth color difference interval ΔE4 is defined. Generate separately. According to the above inequalities (10) to (12), there is no overlapping part in the range of color values that can be taken by a plurality of color patches included in each fourth-layer patch group.
As described above, the color selection color chart CH0 is generated.

When the patch group is formed in the fifth or higher hierarchy, the host device 100 may perform the same processing as in S160 to S170 between S170 and S180 for the number of hierarchies.
When forming a patch group up to the third hierarchy at the maximum, the processes of S160 to S170 may be omitted from the color selection color chart print control process.
Further, when the patch group is set up to the second layer, the processing of S140 to S170 may be omitted from the color chart print control processing for color selection.

From the obtained color selection color chart CH0, the color value of each color patch P0 is obtained by measuring the color of each color patch P0 using the colorimeter 120 shown in FIG. In calculating the color difference intervals ΔE1, ΔE2, ΔE3, and ΔE4, any one of ΔE ₀₀ , ΔE ^* ₉₄ , ΔE ^* _ab , and the like is used. If Delta] E ₀₀ is used as a color difference formula, always Delta] E ₀₀ is used for specifying a color difference interval of the color patches of the patch group included in the color selection for color chart CH0. If Delta] E ^* ₉₄ is used as a color difference formula, always Delta] E ^* ₉₄ is used to identify the color difference interval of the color patches of the patch group included in the color selection for color chart CH0. If Delta] E ^* _ab is used as the color difference formula, always Delta] E ^* _ab is used for specifying the color difference interval of the color patches of the patch group included in the color selection for color chart CH0.

(6) Specific example of color patch search processing:
The obtained color selection color chart CH0 is used for selecting a color patch that matches the target color.
FIG. 10 illustrates a color patch search process performed by the host device 100 illustrated in FIG.

  When the color patch search process is started, the host device 100 causes the display device 130 to display a colorimetric guide screen in S202. FIG. 11 illustrates a colorimetric guide screen 800. At the stage of S202, it is assumed that the color measurement guide screen 800 is provided with a light source selection field 811, a color difference equation selection field 812, and a color measurement start button 813 as initial screens.

In step S204, the host device 100 receives the settings of the colorimetric light source and the color difference formula. In the light source selection field 811, the host device 100 performs a process of receiving, from the input device 115, the settings of the light sources used for color measurement from a plurality of light sources such as the D50 light source, the D65 light source, and the F2 light source. In the color-difference formula selection column 812, the host device 100 displays ΔE ₀₀ shown as ΔE00 in FIG. 11, ΔE ^* ₉₄ shown as ΔE94 in FIG. 11, ΔE ^* _ab shown as ΔE76 in FIG. The input device 115 receives a setting of a color difference formula used for calculating a color difference from a plurality of color difference formulas. Upon receiving an operation on the colorimetric start button 813 by the input device 115, the host device 100 advances the process to S206.

  In step S206, the host device 100 causes the display device 130 to display the colorimetric instruction of the first hierarchical patch group A on the colorimetric guide screen 800. For example, the host device 100 may perform a process of displaying the elements 821 to 825 illustrated in FIG. 11 on the display device 130 as a first-level colorimetric guide screen. The first-level colorimetric guide screen shown in FIG. 11 includes a simulated patch group 821 corresponding to the first-layer patch group A, a colorimetric order display field 822, a target color value display field 823, a color difference display field 824, and A next button 825 is provided. In the simulated patch group 821, the colorimetric order of a plurality of color patches included in the first hierarchical patch group A is indicated by arrows. The colorimetric order display column 822 shows an instruction to prompt the colorimetric device 120 to perform colorimetry of each color patch of the first hierarchical patch group A in order. The target color value display column 823 shows a target color value, for example, a color center value (L0, a0, b0). The color difference display column 824 is a column for displaying the color difference between the colorimetric values of the color patches of the first hierarchical patch group A and the target color values.

  When the user sequentially performs the color measurement of each color patch of the first hierarchical patch group A by the color measurement device 120 according to the instruction in the color measurement order display column 822, the host device 100 performs the process of S208. In step S208, the host device 100 acquires the colorimetric values of each color patch of the first hierarchical patch group A, and measures the colorimetric value of each color patch and the reference measurement according to the color difference equation set in the color difference equation selection field 812. The color difference ΔEp1 from the color value is calculated and displayed in the color difference display column 824. After the colorimetric values of all the color patches of the first hierarchical patch group A have been obtained, the host apparatus 100 simulates, from the simulated patch group 821, the simulated patch corresponding to the color patch with the smallest color difference ΔEp1 in the remaining simulated patches. Display them so that they can be distinguished from patches. In FIG. 11, the simulation patches corresponding to the color patches with the smallest color difference ΔEp1 are shown as simulation patches surrounded by thick lines. In this state, when receiving an operation on the next button 825 by the input device 115, the host device 100 advances the processing to S210.

  In S210, the host device 100 transmits a colorimetric instruction of the second layer patch group associated with the color patch having the smallest color difference ΔEp1 among the plurality of second layer patch groups distinguished on the colorimetric guide screen 800 in S210. It is displayed on the display device 130. For example, the host device 100 may perform a process of displaying the elements 831 to 835 shown in FIG. 12 on the display device 130 as a second-level colorimetric guide screen. FIG. 12 shows the colorimetry of each color patch of the second layer patch group B6 corresponding to the case where the color patch with the symbol P2 from the first layer patch group A shown in FIG. 1 has the minimum value of the color difference ΔEp1. A colorimetric guide screen 800 is shown which prompts the user to perform the color measurement. The second-level colorimetric guide screen 800 shown in FIG. 12 includes a simulated patch group 831 corresponding to the second-level patch group B6, a colorimetric order display field 832, a target color value display field 833, a color difference display field 834, and , And a next button 835 are provided. In the simulated patch group 831, the colorimetric order of a plurality of color patches included in the second hierarchical patch group B6 is indicated by arrows. The colorimetric order display column 832 shows an instruction to prompt the colorimetric device 120 to perform colorimetric measurement of each color patch of the second hierarchical patch group B6 in order. The target color value display column 833 shows a target color value. The color difference display column 834 is a column for displaying a color difference between a colorimetric value of a color patch of the second hierarchical patch group B6 and a target color value.

  When the user sequentially performs the color measurement of each color patch of the second hierarchical patch group B6 by the color measurement device 120 according to the instruction in the color measurement order display column 832, the host device 100 performs the process of S212. In S212, the host device 100 acquires the colorimetric values of the respective color patches of the second hierarchical patch group B6, and calculates the colorimetric values of the respective color patches according to the color difference formula set in the color difference formula selection field 812 in FIG. The color difference ΔEp2 from the reference colorimetric value is calculated and displayed in the color difference display column 834. After the colorimetric values of all the color patches of the second-layer patch group B6 have been obtained, the host device 100 simulates the remaining simulated patches corresponding to the color patches with the smallest color difference ΔEp2 from the simulated patch group 831. Display them so that they can be distinguished from patches. In FIG. 12, the simulation patches corresponding to the color patches with the minimum color difference ΔEp2 are shown as simulation patches surrounded by thick lines.

  After that, in S214, the host device 100 branches the processing depending on whether the hierarchical level Le is 3 or more. If Le <3, there is no patch group in the third and subsequent layers, so the host device 100 proceeds with the process to S226.

When the hierarchy level Le is 3 or more, when the host device 100 receives an operation on the next button 835 by the input device 115, the host device 100 advances the processing to S216.
In S216, the host device 100 transmits a colorimetric instruction of the third layer patch group associated with the color patch having the smallest color difference ΔEp2 among the plurality of distinguished third layer patch groups on the colorimetric guide screen 800. It is displayed on the display device 130. For example, the host device 100 may perform a process of displaying the elements 841 to 845 shown in FIG. FIG. 13 shows a colorimetric content that prompts colorimetry of each color patch of the third hierarchical patch group C5 corresponding to the case where the center color patch from the second hierarchical patch group B6 has the minimum color difference ΔEp2. A guide screen 800 is shown. The third layer colorimetric guide screen 800 shown in FIG. 13 includes a simulated patch group 841 corresponding to the third layer patch group C5, a colorimetric order display field 842, a target color value display field 843, and a color difference display field 844. Is provided. In the simulated patch group 841, the colorimetric order of a plurality of color patches included in the third hierarchical patch group C5 is indicated by arrows. The colorimetric order display column 842 shows an instruction to prompt the colorimetric device 120 to perform colorimetric measurement of each color patch of the third hierarchical patch group C5 in order. The target color value display column 843 shows a target color value. The color difference display column 844 is a column for displaying a color difference between a colorimetric value of a color patch of the third hierarchical patch group C5 and a target color value.

  Note that the colorimetric guide screen 800 shown in FIG. 13 is a screen when the hierarchical level Le is 3, and has a search result display column 845. When the hierarchy level Le is 4 or more, the next button is displayed on the colorimetric guide screen 800 instead of the search result display column 845.

  When the user sequentially performs the color measurement of each color patch of the third hierarchical patch group C5 by the color measurement device 120 according to the instruction in the color measurement order display field 842, the host device 100 performs the process of S218. In S218, the host device 100 acquires the colorimetric value of each color patch of the third hierarchical patch group C5, and calculates the colorimetric value of each color patch according to the color difference equation set in the color difference equation selection field 812 in FIG. The color difference ΔEp3 from the reference colorimetric value is calculated and displayed in the color difference display column 844. After the colorimetric values of all the color patches of the third hierarchical patch group C5 have been obtained, the host apparatus 100 sets the remaining simulated patches corresponding to the color patches with the smallest color difference ΔEp3 from the simulated patch group 841 to the remaining simulated patches. Display them so that they can be distinguished from patches. In FIG. 13, the simulation patches corresponding to the color patches with the smallest color difference ΔEp3 are shown as simulation patches surrounded by thick lines.

  Thereafter, in S220, the host device 100 branches the processing depending on whether or not the hierarchy level Le is 4. If Le = 4, there is no patch group in the fourth hierarchy, so the host device 100 proceeds with the process to S226.

In a case where the hierarchy level Le is 4, the host device 100 proceeds with the process to S222 upon receiving an operation on the next button by the input device 115.
In S222, the host device 100 displays, on the colorimetric guide screen, a colorimetric instruction of the fourth hierarchical patch group associated with the color patch having the smallest color difference ΔEp3 among the plurality of fourth hierarchical patch groups that have been distinguished. It is displayed on the device 130. Although not shown, a screen similar to the third-level colorimetric guide screen shown in FIG. 13 can be used as the fourth-level colorimetric guide screen.

  When the user sequentially performs the color measurement of each color patch of the fourth layer patch group by the color measurement device 120 according to the instruction in the color measurement order display column, the host device 100 performs the process of S224. In S224, the host device 100 acquires the colorimetric values of the respective color patches of the fourth hierarchical patch group, and according to the color difference formula set in the color difference formula selection column 812 of FIG. Is calculated and displayed in the color difference display column. After the colorimetric values of all the color patches of the fourth hierarchical patch group have been obtained, the host device 100 converts the simulated patches corresponding to the color patches with the smallest color difference ΔEp4 from the simulated patch groups from the remaining simulated patches. Display them so that they can be distinguished.

  After that, in S226, the host device 100 acquires the CMYK values of the color patches whose color difference from the reference colorimetric value is minimum. Since the CMYK values of each color patch have been determined to generate the color selection color chart CH0, the host apparatus 100 sets the CMYK values for generating the color patch with the minimum color difference from the reference colorimetric value. What should I do? Here, when the hierarchical level Le is 2, the CMYK values of the color patches with the minimum color difference ΔEp2 are obtained, and when the hierarchical level Le is 3, the CMYK values of the color patches with the minimum color difference ΔEp3 are obtained. The value is acquired, and when the hierarchy level Le is 4, the CMYK value of the color patch with the minimum color difference ΔEp4 is acquired. The color patch with the smallest color difference from the reference colorimetric value is the color patch closest to the target color.

Thus, the color patch search processing ends.
When there is a possibility that a patch group of the fifth or higher hierarchy exists, the host device 100 may perform the same processing as in S220 to S224 between S224 and S226 for the number of hierarchies.
When the patch group is limited to the third hierarchy at the maximum, the processes of S220 to S224 may be omitted from the color patch search process.
Further, when the patch group is limited to the second layer, the processes of S214 to S224 may be omitted from the color patch search process.

  The CMYK value of the color patch having the minimum color difference from the reference colorimetric value can be used, for example, for spot adjustment of the B2A table 502 of the profile 500 shown in FIG.

  FIG. 14 schematically illustrates spot adjustment at the adjustment point P. The spot adjustment shown in FIG. 14 uses the CMYK values (Cp, Mp, Yp, Kp) associated with the coordinate values (Lp, ap, bp) of the adjustment point P in the B2A table 502 stored in the profile 500. This shows how to change it. The coordinate value (Lp, ap, bp) of the adjustment point P is, for example, a color center value (L0, a0, b0), which is the above-described reference color value. Here, the CMYK values of the color patch having the minimum color difference from the reference colorimetric value are defined as (Cq, Mq, Yq, Kq). The CMYK values (Cq, Mq, Yq, Kq) are made to correspond to the coordinate values (Lp, ap, bp) of the adjustment point P instead of the CMYK values (Cp, Mp, Yp, Kp) before adjustment. The B2A table 502 will be adjusted. When there are a plurality of adjustment points P, the B2A table 502 is adjusted so that the changed CMYK values are associated with each adjustment point P. The CMYK values associated with the periphery of the adjustment point P in the Lab color space are changed by smoothing processing, for example, at a rate corresponding to the distance from the adjustment point P. The adjusted B2A table 502 is stored in the profile 500.

  The A2B table 501 stored in the profile 500 can be adjusted to change the Lab value based on the adjusted B2A table 502. The adjusted A2B table 501 is stored in the profile 500.

  As described above, in the color chart CH0 for color selection of this specific example, a plurality of patch groups are arranged in a hierarchical manner with distinction, and the color difference intervals of the color patches of the patch groups become narrower as the hierarchy becomes deeper. I have. For example, in the color chart CH1 shown in FIGS. 1 and 2A, it is assumed that the first color patch P1 is selected from the first patch group G1 having a relatively wide first color difference interval ΔE1 as being close to the target color. In this case, a color patch closer to the target color can be selected from the second patch group G2 having the second color difference interval ΔE2 which is relatively narrow in the first range 301 including the color value of the first color patch P1. It is also assumed that the second color patch P2 is selected as being close to the target color from the first patch group G1 having a relatively wide first color difference interval ΔE1. In this case, a color patch closer to the target color can be selected from the third patch group G3 having the second color difference interval ΔE2 which is relatively narrow in the second range 302 including the color value of the second color patch P2.

  Also, in the color chart CH2 shown in FIGS. 3 and 4, it is assumed that the third color patch P3 is selected as being close to the target color from the second patch group G2 having a relatively wide second color difference interval ΔE2. In this case, a color patch closer to the target color can be selected from the fourth patch group G4 having the third color difference interval ΔE3 that is relatively narrow in the third range 303 including the color value of the third color patch P3. Further, it is assumed that the fourth color patch P4 is selected as being close to the target color from the second patch group G2 having the relatively wide second color difference interval ΔE2. In this case, a color patch closer to the target color can be selected from the fifth patch group G5 having the third color difference interval ΔE4 which is relatively narrow in the fourth range 304 including the color value of the fourth color patch P4.

As in the above example, since a plurality of distinct patch groups are hierarchized, the number of color patches to be searched before searching for a color patch matching the target color can be reduced by tracing the hierarchy of the patch groups. . Therefore, in this specific example, the work of searching for a color patch that matches the target color can be reduced.
This specific example also shows techniques such as a generation method, a generation program, and a generation apparatus of a color selection color chart that reduces the work of searching for a color patch that matches a target color.

(7) Modification:
Various modifications of the present invention are conceivable.
For example, the output device is not limited to an inkjet printer, but may be an electrophotographic printer such as a laser printer using a toner as a color material, a three-dimensional printer, or the like.
The types of color materials for forming an image are not limited to C, M, Y, and K. In addition to C, M, Y, and K, Lc, Lm, DY, Or, ie, orange, Gr, green, Lk, image quality An uncolored coloring material for improvement may be included.

The processing described above can be changed as appropriate, such as changing the order, omitting a part of the processing, or adding another processing. For example, in the process of FIG. 8, the process of S130 for generating the second-layer patch data can be performed before the process of S120 for generating the first-layer patch data.
In the above-described embodiment, the host device 100 performs the above-described processing, but the present technology is not limited to this example. For example, the colorimetric device 120 can perform the above-described processing. In this case, the colorimetric device 120 does not need to be connected to the host device 100 and can be used stand-alone.

The above-described distinction between the patch groups is not limited to a gap wider than the gap between the color patches in the patch group. For example, it is also possible to surround a patch group with a closed figure such as a frame such as a square, a rectangle with rounded corners, or a closed curve to make a distinction.
In the above-described embodiment, the color patch closest to the target color is searched for by measuring the color patches with a colorimeter. However, the present technology is not limited to this example. For example, the host device 100 receives from the user who has viewed each color patch of the color selection color chart CH0 a selection of a color patch that matches the target color via the input device 115, and acquires the CMYK values of the selected color patch. You may.

(8) Closing:
As described above, according to the present invention, it is possible to provide, by various modes, a technique for reducing the work of searching for a color patch that matches a target color. Needless to say, the above-described basic functions and effects can be obtained even with the technology including only the constituent elements according to the independent claims.
In addition, a configuration in which the configurations disclosed in the above-described examples are replaced with each other or the combination is changed, a known technology and the configurations disclosed in the above-described examples are replaced with each other or the combination is changed. Such a configuration can be implemented. The present invention includes these configurations and the like.

100 host device, 120 colorimetric device, 130 display device, 200 printer, 301 first range, 302 second range, 303 third range, 304 fourth range, 310 overlapping range, 500 ... Profile, 710 ... Color center value input field, 800 ... Color measurement guide screen, CH0, CH1, CH2, CH3 ... Color chart, CL1, CL2 ... Gap, CS1 ... CMYK color space, CS2 ... Lab color space, D1 ... One direction, D2 second direction, G1 first patch group, G2 second patch group, G3 third patch group, G4 fourth patch group, G5 fifth patch group, P0 color patch, P1 ... first color patch, P2 ... second color patch, P3 ... third color patch, P4 ... fourth color patch, PR0 ... color chart generation program for color selection, ST1 ... reference color value Obtaining step, ST2: color difference receiving step, ST3: layer number receiving step, ST10: color chart generating step, ST11: first patch group generating step, ST12: second patch group generating step, ST13: third patch group generating step, ST14: Fourth patch group generation step, ST15: Fifth patch group generation step.

Claims (9)

A color chart for color selection for selecting a color patch that matches a target color from a plurality of color patches,
The color chart for color selection includes a first patch group, a second patch group, and a third patch group,
The first patch group includes a plurality of color patches arranged at a first color difference interval including a first color patch and a second color patch,
The second patch group includes a plurality of color patches arranged at a second color difference interval narrower than the first color difference interval,
The third patch group includes a plurality of color patches arranged at the second color difference interval,
Assuming that the color values are coordinate values in the device independent color space,
The color value of the first color patch is included in a first range of possible color values of a plurality of color patches included in the second patch group,
The color value of the second color patch is included in a second range of possible color values of a plurality of color patches included in the third patch group,
A color chart for color selection, wherein at least a part of the first range does not overlap with the second range, and at least a part of the second range does not overlap with the first range. The first patch group, the second patch group, and a plurality of color patches are arranged in a first direction and a second direction crossing each other in the third patch group,
The color values of the plurality of color patches arranged in the first direction change a first coordinate component in the device-independent color space,
2. The color selection color chart according to claim 1, wherein the color values of the plurality of color patches arranged in the second direction have different second coordinate components in the device-independent color space. The color chart for color selection further includes a fourth patch group that is distinguished, and a fifth patch group that is distinguished,
The fourth patch group includes a plurality of color patches arranged at a third color difference interval narrower than the second color difference interval,
The fifth patch group includes a plurality of color patches arranged at the third color difference interval,
The second patch group includes a third color patch and a fourth color patch,
The color value of the third color patch is included in a third range of color values that can be taken by a plurality of color patches included in the fourth patch group,
The color value of the fourth color patch is included in a fourth range of color values that can be taken by a plurality of color patches included in the fifth patch group,
The color according to claim 1 or 2, wherein at least a part of the third range does not overlap with the fourth range, and at least a part of the fourth range does not overlap with the third range. Color chart for selection. A color selection color chart generation method for generating a color selection color chart for selecting a color patch that matches a target color from a plurality of color patches,
The color chart for color selection includes a first patch group, a second patch group, and a third patch group,
The color chart generation method for color selection,
A reference color value acquisition step of acquiring a reference color value;
A first patch group generating step of generating a first patch group including a plurality of color patches arranged at a first color difference interval including a first color patch and a second color patch based on the reference color value; ,
In a first range of color values that can be taken by a plurality of color patches included in the second patch group and in a first range including a color value corresponding to the first color patch, the first color difference interval is narrower. A second patch group generation step of generating a second patch group including a plurality of color patches arranged at a second color difference interval,
In a second range of color values that can be taken by a plurality of color patches included in the third patch group, and in a second range including color values corresponding to the second color patches, the color patches are arranged at the second color difference interval. A third patch group generating step of generating a third patch group including the plurality of color patches,
At least a part of the first range does not overlap with the second range, and at least a part of the second range does not overlap with the first range. The first patch group, the second patch group, and a plurality of color patches are arranged in a first direction and a second direction crossing each other in the third patch group,
The color values of the plurality of color patches arranged in the first direction have a first coordinate component in a device-independent color space that changes.
The color selection color chart generation method according to claim 4, wherein the color values of the plurality of color patches arranged in the second direction have different second coordinate components in the device-independent color space.   The color chart generation method for color selection according to claim 4 or 5, further comprising a color difference receiving step of receiving the setting of the first color difference interval. The first patch group, the second patch group, and a hierarchy number receiving step of receiving the setting of the hierarchy number of the patch group including the third patch group,
The second patch group includes a third color patch and a fourth color patch,
When the number of layers is three or more, the color selection color chart further includes a distinguished fourth patch group, and a distinguished fifth patch group,
The color chart generation method for color selection,
A third range of color values that can be taken by a plurality of color patches included in the fourth patch group when the number of layers is three or more, and a third range including a color value corresponding to the third color patch In the fourth patch group generating step of generating a fourth patch group including a plurality of color patches arranged in a third color difference interval narrower than the second color difference interval,
A fourth range of color values that can be taken by a plurality of color patches included in the fifth patch group when the number of layers is three or more, and a fourth range including a color value corresponding to the fourth color patch; A fifth patch group generation step of generating a fifth patch group including a plurality of color patches arranged at the third color difference interval,
7. The device according to claim 4, wherein at least a part of the third range does not overlap with the fourth range, and at least a part of the fourth range does not overlap with the third range. The method for generating a color chart for color selection according to the above section. A color selection color chart generation program for generating a color selection color chart for selecting a color patch that matches a target color from a plurality of color patches,
The color chart for color selection includes a first patch group, a second patch group, and a third patch group,
The color chart generation program for color selection,
A reference color value acquisition function for acquiring a reference color value,
A first patch group generation function of generating a first patch group including a plurality of color patches arranged at a first color difference interval including a first color patch and a second color patch based on the reference color value; ,
In a first range of color values that can be taken by a plurality of color patches included in the second patch group and in a first range including a color value corresponding to the first color patch, the first color difference interval is narrower. A second patch group generation function for generating a second patch group including a plurality of color patches arranged at a second color difference interval,
In a second range of color values that can be taken by a plurality of color patches included in the third patch group and in a second range that includes color values corresponding to the second color patches, the color patches are arranged at the second color difference interval. A third patch group generation function of generating a third patch group including a plurality of color patches,
At least a part of the first range does not overlap with the second range, and at least a part of the second range does not overlap with the first range. A color selection color chart generation device that generates a color selection color chart for selecting a color patch that matches a target color from a plurality of color patches,
The color chart for color selection includes a first patch group, a second patch group, and a third patch group,
The color selection color chart generation device,
A reference color value acquisition unit that acquires a reference color value;
A first patch group generation unit configured to generate a first patch group including a plurality of color patches arranged at a first color difference interval including a first color patch and a second color patch based on the reference color value; ,
In a first range of color values that can be taken by a plurality of color patches included in the second patch group and in a first range including a color value corresponding to the first color patch, the first color difference interval is narrower. A second patch group generation unit that generates a second patch group including a plurality of color patches arranged at a second color difference interval,
In a second range of color values that can be taken by a plurality of color patches included in the third patch group, and in a second range including color values corresponding to the second color patches, the color patches are arranged at the second color difference interval. A third patch group generation unit that generates a third patch group including a plurality of color patches,
At least a part of the first range does not overlap with the second range, and at least a part of the second range does not overlap with the first range.

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