Color verification system, color verification method, and color verification program

Abstract

To provide a color verification system capable of performing color verification according to a required color quality level.SOLUTION: A color verification system performs color verification of a specific image formed by an image forming device, and is equipped with an information processing device that determines tolerances to be used for color verification of specific colors constituting the specific image on the basis of the attributes of the specific image composed of the specific colors and the purpose of printed matter on which the specific image is formed.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] The technology disclosed in the following Patent Document 1 is a technology for verifying the color quality of an image formed by an image forming apparatus. Patent Document 1 describes the following color verification procedure. First, a user sets color reference data to be used when performing color verification. The color reference data is a reference name and an allowable condition for each reference name. The allowable condition is an allowable value such as an average color difference or a maximum color difference. The CPU of the client computer calculates the color difference between the colorimetric data of a color patch measured using a colorimetric unit and the reference value of the color reference set by the user. The colorimetric data and the reference value are Lab values ​​in the Lab color space. Next, the CPU of the client computer compares the calculated color difference with the allowable value of the color difference of the color reference, and judges it to be OK (good) if the calculated color difference is equal to or less than the allowable value. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-172703 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the color standard data used in color verification is a standard name and an acceptable condition for each standard name, and only one acceptable condition is set for each standard name. Therefore, it is not possible to perform color verification that takes into consideration what kind of printed matter or type of image a color having that standard name is intended to form. As a result, even when the required color quality level is not high for printed matter or image formation, if the color verification result is non-compliant, a worker with specialized skills must spend time adjusting the color.

[0005] SUMMARY OF THE PRESENT EMBODIMENTS An object of the present invention is to provide a color verification system, a color verification method, and a color verification program that are capable of verifying colors under allowable conditions according to a required color quality level. [Means for solving the problem]

[0006] To achieve this objective, the present invention is a color verification system that performs color verification of a specific image formed by an image forming device, and is equipped with an information processing device that determines tolerances to be used for color verification of specific colors that constitute the specific image based on the attributes of the specific image that is composed of specific colors and the purpose of the printed material on which the specific image is formed. Effect of the Invention

[0007] According to the present invention, it is possible to provide a color verification system, a color verification method, and a color verification program capable of performing color verification according to a required color quality level. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing the overall configuration of a color verification system according to the first embodiment. [Diagram 2] FIG. 2 is a diagram showing a color verification information table held by the server device of the color verification system according to the first embodiment. [Diagram 3] FIG. 3 is a flowchart showing the color verification method according to the first embodiment. [Figure 4]FIG. 4 is a diagram showing an example of a verification result displayed on the display unit. [Diagram 5] FIG. 5 is a flowchart showing the main steps of the color verification method according to the second embodiment. [Figure 6] FIG. 6 is a diagram showing grouping of correct values ​​in the color verification method according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, each embodiment of the present invention will be described in detail with reference to the drawings. In each embodiment, the same components are given the same reference numerals, and duplicated explanations will be omitted.

[0010] First Embodiment <Color Verification System> FIG. 1 is an overall configuration diagram of a color verification system 1 according to a first embodiment. The color verification system 1 shown in FIG. 1 is a system for performing color verification of a spot color (hereinafter referred to as a pseudo spot color) formed by adjusting process color inks prior to image formation using the process color inks. Such a color verification system 1 has an information processing device 10 and a server device 20. The information processing device 10 and the server device 20 are network-connected via a communication line 30. The number of information processing devices 10 is not limited to one, and it is preferable that a plurality of information processing devices 10 are network-connected to the server device 20 via the communication line 30.

[0011] [Information processing device 10] Among these, the information processing device 10 is a so-called computer, and may be a client computer owned by each user who uses this color verification system 1. Furthermore, the information processing device 10 may be incorporated in, for example, the image forming device 2. Such an information processing device 10 may be connected to a colorimeter 3. Note that the colorimeter 3 may be incorporated in the image forming device 2.

[0012] Each information processing device 10 includes an operation unit 11, a display unit 12, and an information processing unit 13. The information processing unit 13 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and a network interface. The information processing unit 13 performs color verification by having the CPU read out a predetermined program from the ROM, load it into the RAM, and execute the loaded program.

[0013] The information processing unit 13 determines a tolerance for color verification of the specific color based on the attributes of the specific image composed of the specific color and the purpose of the printed matter on which the specific image is formed. The specific color is a pseudo spot color formed by adjusting process color inks, and the specific image is a spot color image composed of the pseudo spot color. The information processing unit 13 also determines whether the color of the image formed by the pseudo spot color is within the tolerance range. Note that the detailed procedure of color verification by the information processing unit 13 will be described in detail in the color verification method described below.

[0014] [Server device 20] The server device 20 is preferably, for example, a cloud server device, and holds a database for color verification. Fig. 2 is a diagram showing a color verification information table 20t held by the server device 20 of the color verification system 1 according to the first embodiment. The color verification information table 20t holds target information and tolerance information with information numbers (No.). The target information is information about spot color images formed of pseudo spot colors among images printed and formed by the image forming device 2, and in this case, is information about spot color images formed by substituting process color inks for spot color inks.

[0015] The target information includes information on the spot color name, correct value, attribute, and purpose of the spot color image. The spot color name is the name of the spot color ink. The correct value is the color of the spot color ink that the pseudo spot color is targeted to, and is expressed as Lab values ​​(L*, a*, b*). The attribute is the type of the spot color image, such as an image showing brand information such as a mark, brand, trademark, corporate logo, or product logo, or an image of the product itself. The purpose is the form of the printed matter in which the spot color image is printed. Specific examples of purposes include business cards, flyers, POP, posters, and catalogs.

[0016] The tolerance information is the tolerance (ΔL, Δa, Δb, ΔE00) of the color difference between the color measurement value of the pseudo spot color formed by adjusting the process color ink and the correct value of the spot color targeted by the pseudo spot color. This tolerance is a value set for each spot color, attribute, and purpose. In other words, even if the spot color name and correct value are the same, if the attribute of the spot color image and the purpose of the printed matter on which the spot color image is formed are different, the tolerance associated with those information numbers (No) may be different. In this case, the range of the tolerance is set narrower for attributes and purposes that require a high color quality level. Specifically, information numbers (No) No. 1 and No. 5 are the same spot color, but the attribute of the spot color image (Company A logo / Company C product) and the purpose (business card / catalog) are different, so the tolerance is different.

[0017] <Color verification method> Fig. 3 is a flowchart showing the color verification method according to the first embodiment. The procedure shown in this flowchart is executed by a color verification program held by each information processing device 10 in the color verification system 1 described with reference to Fig. 1. The color verification method according to the first embodiment will be described below in accordance with the procedure shown in Fig. 3 and with reference to Figs. 1 and 2.

[0018] [Step S101] In step S101, the information processing unit 13 acquires target information for color verification. The target information is information about a spot color image formed by substituting a process color for a spot color among images printed and formed by the image forming apparatus 2. The target information acquired here is the correct answer value or spot color name of the spot color image, the attribute of the spot color image, and the use of the product on which the spot color image is formed.

[0019] Such information about the spot color image is acquired by a user's input from the operation unit 11.

[0020] [Step S102] In step S102, the information processing unit 13 extracts a tolerance value for color verification from the information held by the server device 20 based on the target information acquired in step S101. At this time, the information processing unit 13 selects an information number (No.) having information matching the target information acquired in step S101 from a color verification information table 20t (FIG. 2) held by the server device 20. Then, the information processing unit 13 extracts a tolerance value held in association with the selected information number (No.).

[0021] If there is no information matching the target information acquired in step S101 in the color verification information table 20t held by the server device 20, the information processing unit 13 selects an information number (No) having information with similar attributes or matching use. Similar attributes here means that everything except the company name indicated in the attributes matches. If there are multiple selectable information numbers (No), the information number (No) with the matching spot color name or correct value is selected with priority, and the information number with the matching use is selected with second priority. In this case, the information processing unit 13 extracts the allowable value of the selected information number (No) as a provisional allowable value.

[0022] [Step S103] In step S103, the information processing unit 13 acquires the colorimetric values ​​of the chart image. This chart image is a test image printed using pseudo-spot colors obtained by adjusting process color inks to obtain the correct values ​​of the colors of the spot color image acquired in step S101 or the colors of the spot color names. The colorimetric values ​​of the chart image acquired by the information processing unit 13 are values ​​obtained by measuring the color of the chart image with the colorimeter 3. The information processing unit 13 acquires the colorimetric values ​​of the chart image from the colorimeter 3 connected to the information processing device 10 or the colorimeter 3 incorporated in the image forming device 2, or acquires the colorimetric values ​​of the chart image by input from the operation unit 11 by the user.

[0023] [Step S104] In step S104, the information processing unit 13 performs color verification based on the correct answer value of the target information acquired in step S101 and the color measurement value acquired in step S103. The color verification by the information processing unit 13 is as follows.

[0024] First, the information processing unit 13 calculates the color difference between the correct value of the target information acquired in step S101 and the colorimetric value 12b acquired in step S103. Next, the information processing unit 13 compares the calculated color difference with the allowable value (or provisional allowable value) extracted in step S102, and judges whether all the color differences are within the allowable value (or provisional allowable value). Then, if all the calculated color differences or the color difference ΔE00 is within the allowable value (or provisional allowable value), the verification result is judged to be good (OK). The information processing unit 13 causes the display unit 12 to display the verification result.

[0025] Fig. 4 is a diagram showing an example of the verification result displayed on the display unit 12. As shown in Fig. 4, the display unit 12 displays color verification information 12a including the target information acquired in step S101 and the allowable value (or the provisional allowable value) extracted in step S102. The display unit 12 also displays the colorimetric value 12b acquired in step S103, the calculated color difference 12c, and a determination result 12d indicating whether the color difference is within the allowable value range. The display unit 12 also displays a color verification result 12e. Note that if the allowable value extracted in step S102 is the provisional allowable value, the information number (No) of the color verification information 12a is left blank.

[0026] [Step S105] In step S105, the information processing unit 13 judges whether or not to perform color adjustment. This judgment is made based on an input by the user from the operation unit 11. In this case, as shown in FIG. 4, for example, the display unit 12 displays a selection unit 12f for selecting whether or not to perform color adjustment together with the verification result.

[0027] The user refers to the above-mentioned chart image (S103) along with the judgment result 12d and color verification result 12e displayed on the display unit 12 and judges whether or not to perform color adjustment. If it is judged that color adjustment is to be performed, the user selects [YES] in the selection unit 12f. This causes the information processing unit 13 to return to step S103 (FIG. 3).

[0028] At this time, the user performs color adjustment of the process color inks. For example, this color adjustment involves correcting the maximum density, gradation, and color conversion table of each process color ink so that the color measurement value falls within the tolerance extracted in step S102. The user then prints and forms a chart image using the color-adjusted process color inks, and performs color measurement of the chart image. The color measurement value of the chart image obtained by this color measurement is acquired by the information processing unit 13 in step S103, and thereafter, steps S104 and onward are repeated.

[0029] On the other hand, if the user selects [NO] in the selection section 12f (see FIG. 4), the information processing section 13 determines that color adjustment is not to be performed (NO), and proceeds to step S106.

[0030] [Step S106] In step S106, the information processing unit 13 judges whether or not the target information acquired in step S101 is present in the color verification information table 20t (see FIG. 2) of the server device 20. At this time, if the information processing unit 13 has been able to select an information number (No) having information matching the target information acquired in step S101 in step S102, it judges that the information is present (YES) and proceeds to step S107.

[0031] On the other hand, if a provisional tolerance is extracted in step S102, that is, if the information number (No) of the color verification information 12a shown in Fig. 4 is blank, the information processing unit 13 determines that there is no target information acquired in step S101 in the server device 20 (NO), and proceeds to step S107a.

[0032] [Step S107a] In step S107a, the information processing unit 13 assigns new information numbers (No.) to the target information and the tolerance acquired in step S101, and adds the color verification information to the color verification information table 20t (FIG. 2) of the server device 20. The tolerance to which the new information number (No.) is assigned is either the provisional tolerance extracted in step S102, the color difference calculated in step S104, or a value set by the user. After adding the color verification information to which the new information number (No.) is assigned to the color verification information table 20t (FIG. 2) of the server device 20, the information processing unit 13 ends the process.

[0033] [Step S107] On the other hand, in step S107, the information processing unit 13 judges whether or not to change the allowable value. This allowable value is the allowable value extracted in step S102. This judgment is made based on an input from the user through the operation unit 11. In this case, the display unit 12 displays a selection unit for selecting whether or not to change the allowable value (not shown). If the user selects to change the allowable value (YES), the information processing unit 13 proceeds to step S108. On the other hand, if the user selects not to update the allowable value (NO), the information processing unit 13 ends the processing.

[0034] [Step S108] In step S108, the information processing unit 13 causes the display unit 12 to display an operation image for changing the allowable value (not shown). In this case, the information processing unit 13 causes the display unit 12 to display color verification information 12a (see FIG. 4) of the information number (No) selected in step S101 and an execute change button. Among these, the color verification information 12a is displayed so that the allowable value can be rewritten.

[0035] As a result, even if the color verification result is judged to be good (OK) in the color verification process in step S104, the user can rewrite the tolerance in the color verification information 12a of the corresponding information number (No.). The user refers to the above-mentioned chart image (S103) together with the judgment result 12d and color verification result 12e shown in FIG. 4, for example, and changes the current tolerance to a smaller or larger value. The user also selects the execute button after rewriting the tolerance. As a result, the information processing unit 13 changes the tolerance of the corresponding information number (No.) in the color verification information table 20t held by the server device 20, and ends the process.

[0036] In step S108, the information processing unit 13 may display a selection display for selecting whether or not to use the color difference calculated in step S104 as a new allowable value on the display unit 12. In this case, when the user selects to use the color difference calculated in step S104 as a new allowable value, the information processing unit 13 rewrites the allowable value in the color verification information table 20t to the color difference calculated in step S104, and ends the process.

[0037] <Advantages of the First Embodiment> According to the first embodiment described above, when forming a spot color image by substituting process color ink for spot color ink, color verification can be performed according to the required color quality level by setting tolerances for the attributes of the spot color image and the purpose of the printed matter on which the spot color image is formed. As a result, unnecessary color adjustments based on judgment results at a color quality level higher than necessary can be reduced.

[0038] Second Embodiment The second embodiment is a modification of the first embodiment, and is an example in which acquisition of target information in step S101 shown in the flowchart of FIG. 3 in the color verification method of the first embodiment is automated.

[0039] <Color verification method> Fig. 5 is a flowchart showing the main steps of a color verification method according to the second embodiment, and shows steps that are performed in place of step S101 in the flowchart of Fig. 3. The steps shown in this flowchart are steps that are performed by a color verification program held by the information processing unit 13 of each information processing device 10 in the color verification system 1 described using Fig. 1. Below, the color verification method of the second embodiment will be described according to the steps shown in Fig. 5, with reference to Figs. 1 and 2.

[0040] [Step S201] In step S201, the information processing unit 13 acquires information on a job image to be printed by the image forming apparatus 2. The information processing unit 13 acquires information on the job image via a network interface of the information processing device 10, or, when the information processing device 10 is incorporated in the image forming apparatus 2, may acquire the information on the job image from an image reading unit of the image forming apparatus 2.

[0041] [Step S202] In step S202, the information processing unit 13 extracts a spot color image from the job image acquired in step S201. In this case, the server device 20 has a database related to spot color images. The information processing unit 13 extracts the spot color image from the job image by referring to the database related to spot color images held by the server device 20. Note that if the server device 20 does not have a database related to spot color images, the information processing unit 13 may extract the spot color image from the job image by performing an image search on a network. This network may be a global network connected to the external Internet.

[0042] [Step S203] In step S203, the information processing unit 13 determines attributes of the spot color image extracted in step S202. The information processing unit 13 refers to a database related to spot color images held by the server device 20, and extracts attributes associated with the spot color image extracted in step S202. In addition, if the server device 20 does not have a database related to spot color images, the information processing unit 13 may determine attributes of the spot color image by performing an image search on a network.

[0043] [Step S204] In step S204, based on the job image information acquired in step S201, the information processing unit 13 determines the purpose of the printed matter to be image-formed by the image forming apparatus 2. At this time, the information processing unit 13 determines the purpose of the printed matter based on the size of the printed matter and the overall image to be formed, and ends the process.

[0044] After the above, the information processing unit 13 proceeds to step S102 in Fig. 3. At this time, the information processing unit 13 extracts a tolerance value for color verification based on the attribute determined in step S203 and the use determined in step S204 of the target information. That is, the information processing unit 13 selects an information number (No.) having information that matches the attribute determined in step S203 and the use determined in step S204 from the color verification information table 20t (Fig. 2) held by the server device 20. Then, the information processing unit 13 extracts a tolerance value held in association with the selected information number (No.). Note that, as described in step S102 of the first embodiment, the tolerance value may be a provisional tolerance value. Thereafter, the procedure described in the first embodiment is carried out.

[0045] <Effects of the second embodiment> According to the second embodiment, in addition to the effects of the first embodiment, it is possible to automate the acquisition of information for color verification.

[0046] Third Embodiment The third embodiment is a modified example of the first embodiment, and is an example of a color verification method when the color verification information table 20t shown in FIG. 2 in the color verification method of the first embodiment does not contain color verification information including target information.

[0047] 3, the information processing unit 13 extracts an allowable value for color verification from the information held by the server device 20 based on the target information acquired in step S101, as described in the first embodiment. At this time, if there is no information matching the target information acquired in step S101 in the color verification information table 20t held by the server device 20, in the third embodiment, the information processing unit 13 determines the allowable value as follows.

[0048] That is, the information processing unit 13 determines the allowable value based on the correct value of the target information acquired in step S101 and the history information of the color verification. In this case, the server device 20 has data related to past color verifications. This data is data in which the correct value of the color verified in the past is plotted in the Lab color space.

[0049] Fig. 6 is a diagram showing grouping of correct values ​​in the color verification method according to the third embodiment. As shown in Fig. 6, the information processing unit 13 plots the correct value 301 acquired in step S101 in the Lab color space in the database, and groups (clusters) data of past correct values ​​that are close to this correct value 301. The program for grouping is not particularly limited.

[0050] The information processing unit 13 calculates the average value of the allowable values ​​corresponding to each correct value in the group 302, and sets this average value as the allowable value for the correct value.

[0051] <Effects of the third embodiment> According to the third embodiment, even if the color verification information table 20t of the server device 20 does not contain color verification information including target information, the allowable value can be set based on the history information of past color verifications. [Explanation of symbols]

[0052] 1. Color verification system 2. Image forming device 3 Colorimeter 10...Information processing device 11...Operation unit 12...Display section 13...Information processing section 20...Server equipment 30…Communication lines 301...Correct value 302...Group

Claims

1. A color verification system for performing color verification of a specific image formed by an image forming apparatus, comprising: and an information processing device that determines a tolerance used for color verification of a specific color constituting the specific image based on an attribute of the specific image constituted by the specific color and a purpose of a printed matter on which the specific image is formed. Color verification system.

2. the specific image is an image formed by substituting a process color ink for a spot color ink, The specific color is a special color. The color verification system of claim 1 .

3. The attribute of the specific image is the type of the specific image. The color verification system of claim 1 .

4. a server device that stores the permissible value set according to at least one of an attribute of the specific image and an intended use of the printed matter; The information processing device includes: Extracting one of the allowable values ​​from the allowable values ​​stored in the server device based on the attribute of the specific image and information regarding the purpose of the printout. The color verification system of claim 1 .

5. the server device stores a correct answer value of the specific color constituting the specific image in association with an attribute of the specific image and an application of the printed matter; The information processing device determines whether or not a color difference between a color measurement value of the image of the specific color formed by the image forming device and a correct value of the specific color is within a range of the extracted allowable value. The color verification system of claim 4.

6. The tolerance of the color verification is represented by ΔL, Δa, Δb, and ΔE00, which are the differences from the coordinates of the correct value in the Lab color space. The color verification system of claim 5 .

7. The information processing device includes: Obtaining document image data of a print job for the image forming apparatus, extracting the specific image from the obtained document image data, and determining attributes of the extracted specific image. The color verification system of claim 1 .

8. a server device that holds a database relating to the specific image; The information processing device refers to the database to extract the specific image from the document image data, and determines attributes of the extracted specific image. The color verification system of claim 7.

9. The information processing device extracts the specific image by image search on a network, and determines attributes of the extracted specific image. The color verification system of claim 7.

10. The information processing device determines a purpose of the printed matter based on size information of the printed matter and layout information of images in the printed matter. The color verification system of claim 1 .

11. The information processing device determines an allowable value to be used in color verification of the specific color based on history information of the color verification. The color verification system of claim 1 .

12. The information processing device plots, in a Lab color space, the correct answer values ​​of the specific color for which color verification has been previously performed based on the history information, groups the correct answer values ​​in the Lab color space that are close to the correct answer value of the specific color to be color verified, and sets the average of the allowable values ​​corresponding to the grouped correct answer values ​​as the allowable value to be used for color verification of the specific color to be verified. The color verification system of claim 11.

13. The information processing device records the color verification history information in a server device on a cloud. The color verification system of claim 11.

14. A method for verifying a color of a specific image formed by an image forming apparatus, comprising: A tolerance value used for color verification of a specific color constituting the specific image is determined based on attributes of the specific image constituted by the specific color and the purpose of the printed matter on which the specific image is formed. Color verification method.

15. a server device stores the permissible value set according to at least one of an attribute of the specific image and an application of the printout; An information processing device extracts one of the allowable values ​​from the allowable values ​​stored in the server device based on the attribute of the specific image and information related to the use of the printed matter. The color verification method of claim 14.

16. the server device stores a correct answer value of the specific color constituting the specific image in association with an attribute of the specific image and an application of the printed matter; The information processing device determines whether or not a color difference between a color measurement value of the image of the specific color formed by the image forming device and a correct value of the specific color is within a range of the extracted allowable value. The color verification method of claim 15.

17. A color verification program for a specific image formed by an image forming apparatus, comprising: The information processing device determines a tolerance used for color verification of a specific color constituting the specific image based on an attribute of the specific image constituted by the specific color and a purpose of a printed matter on which the specific image is formed. Color verification program.

18. storing the permissible value set in accordance with at least one of an attribute of the specific image and an intended use of the printed matter in a server device; The information processing device extracts one of the allowable values ​​from the allowable values ​​stored in the server device based on the attribute of the specific image and information on the use of the printed matter. The color verification program according to claim 17.

19. storing, in the server device, a correct value of the specific color constituting the specific image in association with an attribute of the specific image and an application of the printed matter; The information processing device determines whether or not a color difference between a color measurement value of the image of the specific color formed by the image forming device and a correct value of the specific color is within a range of the extracted allowable value. The color verification program according to claim 18.

Images