JP4345669B2 - Measurement of colorimetric values using an image input device - Google Patents

Description

  The present invention relates to a technique for obtaining a colorimetric value of a color of a predetermined target part, and more particularly to a technique for obtaining a colorimetric value of a color of a target part using an image input device such as a scanner.

  The adjustment of the printing characteristics of the printing apparatus includes, for example, printing the data of the sample chart with the printing apparatus to be adjusted, and comparing the colorimetric value obtained by measuring the color of the printed image with a preset desired colorimetric value. (For example, Patent Document 1). Color measurement of a printed image is generally performed using a colorimeter.

JP 2000-209450 A JP 2002-204370 A JP 2002-262106 A

  In the adjustment of the printing characteristics of the printing apparatus, instead of using the colorimetric value obtained by the colorimeter, an input value obtained by inputting a print image using a relatively inexpensive image input apparatus such as a scanner can be used. The printing characteristics can be adjusted economically. However, since the image input device is not originally a device for color measurement, when the image input device is used for adjusting the printing characteristics of the printing device, the input value by the image input device is associated with the color measurement value by the colorimeter. It is desirable that

  In addition, after the input value and the colorimetric value are associated with each other, an accident or an apparatus failure such as contamination of the image reading table of the scanner or a lamp out of the image reading table may occur. In such a case, the image input device does not exhibit the performance when the input value by the image input device is associated with the color measurement value by the colorimeter. As a result, even if the input value is accurately associated with the colorimetric value, the printing characteristics of the printing apparatus cannot be adjusted correctly.

  Such a problem is not limited to the adjustment of the printing characteristics of the printing apparatus, but is a common problem when the input value from the image input apparatus is used instead of the colorimetric value from the colorimeter.

  The present invention has been made to solve the above-described conventional problems, and when an image input device is used to obtain a colorimetric value of a color of a target portion, the image input device is inspected within a predetermined period. The purpose is to provide technology to confirm that

  In order to solve at least a part of the above problems, the present invention uses an image input device capable of simultaneously reading the colors of a plurality of target portions and generating input values representing the color characteristics of the target portions. When obtaining the colorimetric value of the color of the part, the following processing is performed. That is, first, (a) the image input unit is inspected, and when the inspection result satisfies a predetermined condition, inspection data representing the inspection time is generated. Then, (b) a plurality of target portions are imaged by an image input device, and colorimetric values of the colors of each target portion are obtained based on input values representing the color characteristics of each target portion.

  When obtaining a colorimetric value based on the input value of each target portion, first, an elapsed time from the inspection time in the inspection data is obtained. A warning is issued when the elapsed time exceeds a predetermined period. According to this aspect, when the color measurement value of the color of the target portion is obtained using the image input device, it can be confirmed whether or not the image input device has been inspected within a predetermined period.

  In addition, this invention can also be comprised with the following aspects. That is, this is a method for generating adjustment data for correcting the printing characteristics of a printing apparatus using an image input apparatus. When generating the adjustment data, first, (a) the image input device is inspected, and if the inspection result satisfies a predetermined condition, inspection data including inspection time data is generated. On the other hand, if the result of the inspection does not satisfy a predetermined condition, a warning is issued. Then, (b) a plurality of patches printed using the printing apparatus are imaged by the image input apparatus, and adjustment data is generated based on input values representing the color characteristics of each patch.

  When generating adjustment data based on the input value of each patch, first, (b1) an elapsed time from the inspection time in the inspection data is obtained. (B2) A warning is issued when the elapsed time exceeds a predetermined period. On the other hand, if (b3) the elapsed time is less than the predetermined period, adjustment data is generated. With such an aspect, it is possible to easily and accurately obtain data representing the printing characteristics of the printing apparatus using the image input apparatus that has been inspected within a predetermined time.

  Also, conversion data and color reproduction target data can be prepared in advance and the following processing can be performed. Here, the conversion data is stored by associating a colorimetric value obtained by measuring a predetermined color with a colorimeter and an input value obtained by imaging the predetermined color with an image input device. It is data to be. The color reproduction target data is data that stores colorimetric values of colors to be reproduced by the printing apparatus when given a color designation value that designates a color included in a predetermined series.

  When generating adjustment data, first, (b4) a patch is printed by a printing apparatus based on a sample color designation value that is a color designation value that designates a sample color included in the predetermined series. Then, (b5) the patch is imaged by the image input device, and a target input value that is an input value corresponding to the patch is obtained. Thereafter, (b6) using the converted data, the target input value is converted into a target colorimetric value that is a colorimetric value corresponding to the patch. By performing such processing, a target colorimetric value that does not reflect the bias in performance of the image input apparatus can be obtained for the patch.

  Thereafter, (b7) using the color reproduction target data, the target colorimetric value is converted into an ideal designated value that is a color designated value corresponding to the patch. By performing such processing, an ideal color specification value for causing a printing apparatus having an ideal characteristic to print a patch having the characteristic represented by the target colorimetric value (actually printed) is ideal. The specified value can be obtained. Then, (b8) adjustment data is generated based on the sample color designation value and the ideal designation value.

  According to such an aspect, even if adjustment data is generated using an image input device that may include a predetermined performance bias, adjustment data that allows the printing apparatus to execute printing with characteristics close to ideal characteristics. Can be generated.

The colorimetric value can be the value of L ^* in the L ^* a ^* b ^* color system. According to such an aspect, the characteristics of the printed patch can be evaluated by the lightness (value of L ^* ) which is an absolute reference, and accurate adjustment data can be generated.

  The predetermined series of colors are preferably achromatic colors having different brightness. And when printing a patch, it is preferable to print using black ink with a printing apparatus based on the sample color designation | designated value which designates such an achromatic color.

  Further, when inspecting the image input device, it is preferable to capture a predetermined inspection patch with the image input device to obtain an inspection input value that is an input value corresponding to the inspection patch. The predetermined condition for generating the inspection data is preferably that the inspection input value is within a predetermined range. With such an aspect, it is possible to prevent a situation in which adjustment data for the printing apparatus is generated using an image input apparatus whose performance for generating an input value fluctuates beyond an allowable range. Therefore, it is possible to improve the reliability when generating the adjustment data.

  And when inspecting an image input device, it is also preferable to perform the following processes. That is, first, (a1) a predetermined color patch for inspection is measured with a colorimeter to obtain a reference colorimetric value that is a colorimetric value corresponding to the patch for inspection. On the other hand, (a2) the inspection patch is imaged by an image input device to obtain an inspection input value that is an input value corresponding to the inspection patch. Thereafter, (a3) using the conversion data, the inspection input value is converted into an inspection colorimetric value that is a colorimetric value corresponding to the inspection patch. The predetermined condition for generating the inspection data is that the inspection color measurement value and the reference color measurement value are closer to the predetermined standard.

  According to such an aspect, the image input device can be inspected by comparing the reference colorimetric value obtained by the colorimeter with the inspection colorimetric value obtained by the image input device. Therefore, the performance of generating the input value of the image input device can be accurately evaluated using the colorimeter, and the image input device can be checked.

The colorimetric value is preferably the value of L ^* in the L ^* a ^* b ^* color system. The inspection patch is preferably an achromatic patch.

  The input value can be a gradation value of a red, green or blue color component.

  Note that it is also preferable that the adjustment data is generated by the above-described methods, and the adjustment data is stored in the storage unit of the printing apparatus to manufacture the printing apparatus. With such an aspect, it is possible to manufacture a printing apparatus that can perform good color reproduction based on adjustment data that is accurately set.

  In addition, the present invention can be configured as follows. That is, the system generates adjustment data for correcting the printing characteristics of the printing apparatus. This system is capable of reading the colors of a plurality of target portions at the same time and generating an input value that represents the color characteristics of each target portion. The inspection data including the time data is generated, and when the inspection result does not satisfy a predetermined condition, an imaging inspection unit that issues a warning, and a plurality of patches printed using the printing device, the image input unit And a print adjustment amount setting unit that generates adjustment data based on an input value that represents the color characteristics of each patch, and an elapsed time determination unit that calculates an elapsed time from the inspection time in the inspection data. Prepare. The print adjustment amount setting unit issues a warning when the elapsed time exceeds a predetermined period, and generates adjustment data when the elapsed time is less than the predetermined period.

  The present invention can be implemented in various modes. For example, an image processing method and system, an image input value conversion method and system, a print adjustment amount setting method and system, and the functions of these methods or systems The present invention can be realized in the form of a computer program for realizing, a recording medium recording the computer program, a data signal including the computer program and embodied in a carrier wave, and the like.

Next, embodiments of the present invention will be described in the following order based on examples.
A. Summary of embodiment:
B. Example:
B-1. Image processing system configuration:
B-2. Print adjustment amount setting process:
C. Variations:

A. Summary of embodiment:
The image input value (R value) of the red color component obtained by reading with an image input device and the image colorimetric value (L ^* value) obtained by measuring with a colorimeter for a plurality of patches having different brightness in advance. ) Are created (see the middle left of FIG. 4). Also, an ideal relationship IR, which is data defining the relationship between the tone value G of black ink and the ideal brightness L ^* that the printer should reproduce when the tone value G is given, is created. (Refer to the lower left of FIG. 4).

  When setting the adjustment amount, first, the sample chart SC including the patch j reproduced based on the sample gradation value GSj is printed using the black ink by the printer 500t that is the target of the print adjustment amount setting process. (Refer to the upper left of FIG. 4). The patch j is imaged by the scanner 400, an image input value (R value) of the red color component for the patch j is obtained, and a sample input value file SIF is generated (see the right side of FIG. 4).

Then, based on the LUT file described above, the sample conversion file SCF is generated by replacing the red image input value (R value) with the image colorimetric value (L ^* value). Further, an ideal gradation value GIj representing which gradation value is reproduced when the patch j having the lightness L ^* is reproduced in an ideal printer is based on the above-described ideal relation IR. Ask. Then, an adjustment amount Bj corresponding to the patch j for the printer 500t is obtained by (sample gradation value GSj) / (ideal gradation value GIj). When printing is performed, when a gradation value of a pixel is input, the gradation value is replaced with a value multiplied by Bj, and printing is executed. As a result, when the gradation value GIj is input, the printer 500t reproduces the lightness color having the lightness L ^{* as} in the ideal relation IR.

  The adjustment amount of the printing apparatus is set when the printing apparatus is manufactured. In principle, the LUT file is updated once every 30 days. The scanner 400 is also inspected once every 24 hours to see if the performance has changed significantly. Further, prior to setting the adjustment amount of each printing apparatus, it is checked whether or not the scanner 400 has been inspected within 24 hours after the inspection data is read out. If the scanner 400 has not been inspected within 24 hours, a warning is displayed on the display 120 (see the lower part of FIG. 13). Note that the patch j used in the processing described above and the lookup table in the LUT file are set for each combination of ink nozzles used for printing, usable dot diameters, and printing modes (resolutions).

B. First embodiment:
B-1. Image processing system configuration:
FIG. 1 is an explanatory diagram schematically showing the configuration of an image processing system as a first embodiment of the present invention. The image processing system 10 according to the present embodiment can be used for a print adjustment amount setting process to be described later for setting an adjustment amount B for adjusting the print characteristics of a printer. The image processing system 10 includes a computer 100, a colorimeter 300, and a scanner 400. Further, the image processing system 10 may include a printer 500.

  The computer 100 includes a CPU 110, an internal storage device 200 such as a ROM and a RAM, a display unit 120 such as a display, an operation unit 130 such as a keyboard and a mouse, an external storage device 140 such as a hard disk drive, a current date, A timer 150 for outputting time and an interface unit (I / F unit) 160 are provided. Each component in the computer 100 is connected to each other via a bus 170.

  The internal storage device 200 includes an LUT generation unit 210, a print adjustment amount setting unit 220, an elapsed day determination unit 230, a color measurement processing unit 240, an imaging processing unit 250, a print processing unit 260, and an imaging inspection unit. 270. Each of these units is a computer program that functions as each unit. The LUT generation unit 210 includes an LUT generation date addition unit 212, and the print adjustment amount setting unit 220 includes an input value conversion unit 222 and an ideal relationship IR.

  The color measurement processing unit 240 is a color measurement driver that controls the color measurement device 300, and includes a color measurement date addition unit 242. The imaging processing unit 250 is a scanner driver that controls the scanner 400 and includes a date input / addition unit 252. The print processing unit 260 is a printer driver that controls the printer 500. The imaging inspection unit 270 is application software and determines whether the performance of the scanner 400 is normal. If it is determined to be normal, inspection data is generated, and if it is determined to be abnormal, a warning is displayed on the display 120 connected to the computer 100. The interface unit 160 includes a plurality of input / output terminals, and performs data communication with external devices such as the colorimeter 300, the scanner 400, and the printer 500.

The colorimeter 300 is a device that performs colorimetry on an image and obtains a colorimetric value. In this embodiment, the colorimetric values L ^* , a ^* , and b ^{* in} the L ^* a ^* b ^* color space. Is output. Note that the colorimeter may be any device that can measure a certain color and output the brightness of the color as a colorimetric value. In addition, it is preferable that the colorimeter has a smaller change in performance over time than the image input device.

  The scanner 400 is an apparatus that captures an image and obtains an input value of the image. In this embodiment, the scanner 400 outputs three input values of an R value, a G value, and a B value. In this specification, “imaging” refers to reading the colors of a plurality of target portions at the same time and generating an input value representing the color characteristics of each target portion. The printer 500 is an ink jet printer, and in this embodiment, an image is printed using four colors of inks of C (cyan), M (magenta), Y (yellow), and K (black).

B-2. Print adjustment amount setting process:
FIG. 2 is a flowchart showing the flow of print adjustment amount setting processing by the image processing system of this embodiment. FIG. 3 is an explanatory diagram showing an overview of the preparation of the reference chart BC and the preparation of the LUT file in the print adjustment amount setting process, and FIG. 4 shows the adjustment amount B in the print adjustment amount setting process. It is explanatory drawing which shows the outline | summary of the process of a setting. Here, the print adjustment amount setting process is a process of setting an adjustment amount B for adjusting the print characteristics of the printer to be desirable characteristics. In this embodiment, when an image is printed based on certain image data, an adjustment amount B as a coefficient to be multiplied by the gradation value of the image data is set in order to make the print result desirable. The adjustment amount B is desirably set for each combination of ink nozzles used for printing, usable dot diameters, and printing modes (resolutions).

  In step S100 (see FIG. 2), the user prepares the reference chart BC. The reference chart BC is obtained by printing a plurality of patches by a printer 500 of the same type as the printer that is the target of the print adjustment amount setting process.

  In this embodiment, the reference chart BC is updated every predetermined number of days in consideration of the change in the color characteristics of the reference chart BC and the change in the input characteristics of the scanner 400. In this embodiment, it is assumed that the preparation of the reference chart BC in step S100 is performed once every 90 days.

  FIG. 5 is a flowchart showing the flow of processing for preparing the reference chart BC. In step S110, it is determined whether or not there is an existing reference chart BC. If there is no existing reference chart BC, the process proceeds to step S140, and the reference chart BC is produced (printed). On the other hand, when there is an existing reference chart BC, the process proceeds to step S120.

  In step S120, it is determined whether or not the existing reference chart BC is within the expiration date, that is, whether or not a predetermined number of days have passed since the date of preparation of the reference chart BC. The predetermined number of days is set to 90 days, for example. When it is determined that the existing reference chart BC has exceeded the expiration date, the process proceeds to step S140, and a new reference chart BC is produced. On the other hand, when it is determined that the existing reference chart BC is within the expiration date, the process proceeds to step S130 to prepare the existing reference chart BC.

  FIG. 6 is an explanatory diagram schematically showing the contents of the reference chart BC. The reference chart BC used in this embodiment is composed of N sheets (N is an integer of 2 or more). In addition, a total of 24 patches of 6 rows × 4 columns are printed on each sheet of the reference chart BC. In the following description, each sheet of the reference chart BC is represented by using a sheet number i (i is an integer of 1 to N), and patches in each sheet are patch numbers j (j is 1 to 24). (Integer). A sheet number i is displayed on the upper right of each sheet of the reference chart BC. Also, the patch number j of the upper left patch of each sheet is set to 1, the patch number j of the patch adjacent to the right of the patch of patch number 1 is set to 2, and the patch number j is assigned in the same manner. The patch number j is 24.

  In each sheet of the reference chart BC, the number of rows of patches corresponds to the number of inks used by the printer 500 used for printing the reference chart BC. Since the printer 500 of this embodiment uses four colors of inks of C, M, Y, and K, the number of rows of patches is four. The patch in the first row from the left is printed using a cyan nozzle, the patch in the second row is printed using a magenta nozzle, the patch in the third row is printed using a yellow nozzle, The fourth row of patches is printed using a black nozzle. However, in this embodiment, all patches are printed using black ink. That is, for example, the patch in the first row is printed with black ink using a nozzle that is originally for cyan.

  In this way, by printing patches using black ink, it is possible to reproduce a wide range of brightness, and to easily detect subtle deviations in brightness when scanned with a colorimeter or scanner. Can be printed. In addition, when the printing apparatus that prints the patch includes the photo black ink whose printing result is glossy and the matte black ink whose printing result is not glossy, the matte black ink whose printing result is not glossy More preferably, is used. In addition, since black ink can be manufactured inexpensively, the cost at the time of implementing this embodiment can be reduced.

  In each sheet of the reference chart BC, the number of patch lines corresponds to the type of dot diameter and the number of print modes of the printer 500 used for printing the reference chart BC. The printer 500 according to the present embodiment performs printing using three types of dot diameters of large dots, medium dots, and small dots, and print mode 1 (high resolution mode) and print mode 2 (low resolution mode). ) And two print modes. Therefore, the number of patch lines is six. The patches on the first to third lines from the top are printed using the printing mode 1, and the patches on the fourth to sixth lines are printed using the printing mode 2. The patches on the first and fourth lines are printed using large dots. Similarly, the second and fifth lines use medium dots, and the third and sixth lines use small dots. Used and printed.

  Each sheet of the reference chart BC is printed based on image data having different gradation values G for patches having the same patch number j (patches printed at the same position in each sheet). That is, if the gradation value G of the image data used for printing the patch with the patch number j on the i-th sheet is expressed as “Gij”, the N gradation values from G1j to GNj are all different values. It has become. Therefore, the reference chart BC includes patches printed based on image data having N types of gradation values for each print mode and dot diameter for each ink color nozzle.

  In this embodiment, for each patch number j, the image data used for printing the patch on the first sheet has the largest gradation value G (that is, the patch is dark black), and N sheets The gradation value G of the image data is decreased toward the eye sheet (that is, the patch is light black (gray)). Note that the printing gradation expression in the printer 500 is performed by adjusting the number of dots applied per unit area. In this embodiment, the larger the gradation value D of the image data used for printing the patch, the larger the unit area. The number of dots per dot is increased. Further, the gradation value G of the image data used for printing does not need to be the same between the 24 patches in one sheet, and may be different from each other.

  Furthermore, the date of manufacture (print date) of the reference chart BC is displayed on each sheet of the reference chart BC. In the present embodiment, the N sheets of the reference chart BC are printed on the same day, and the same date is displayed on each sheet.

  FIG. 3 shows a prepared reference chart BC. Although FIG. 3 shows that the reference chart BC is printed by the printer 500 connected to the computer 100 of the image processing system 10, the printer 500 used for printing the reference chart BC is the image processing system 10. It is not necessary to be connected to.

  After completing the preparation of the reference chart BC in step S100 (see FIG. 2), in step S300, the LUT file is prepared. The LUT file is for associating an image input value from the scanner 400 with an image colorimetric value from the colorimeter 300. The contents of the LUT file will be described later.

  In this embodiment, the LUT file is updated every predetermined number of days in consideration of changes in input characteristics of the scanner 400 and the like. That is, the preparation of the LUT file in step S300 is performed once every 30 days in principle. FIG. 7 is a flowchart showing a flow of LUT file preparation processing. In step S310, it is determined whether there is an existing LUT file. If there is no existing LUT file, the process advances to step S400 to generate an LUT file. On the other hand, if there is an existing LUT file, the process proceeds to step S320.

  In step S320, it is determined whether or not the existing LUT file is within the expiration date, that is, whether or not a predetermined number of days have elapsed since the LUT file generation date. For example, the predetermined number of days is set to 30 days. If it is determined that the existing LUT file has exceeded the expiration date, the process proceeds to step S400, and a new LUT file is generated. On the other hand, when it is determined that the existing LUT file is within the expiration date, the process proceeds to step S330 to prepare the existing LUT file.

FIG. 8 is a flowchart showing a flow of processing for generating an LUT file in step S400 of FIG. In step S410, the colorimetric processing unit 240 (see FIG. 1) controls the colorimeter 300 to measure the color of the reference chart BC, and generates a colorimetric value file MF. FIG. 3 shows how the color of the reference chart BC is measured to generate a colorimetric value file MF. FIG. 9 is an explanatory diagram showing an example of the colorimetric value file MF. The colorimetric processing unit 240 measures 24 patches for each of the N sheets of the reference chart BC, and represents the lightness in the L ^* a ^* b ^* color space as an image colorimetric value for each patch. Get the value of ^* . For example, the first and second lines of the colorimetric value file MF shown in FIG. 9 indicate L ^* values of 24 patches in the sheet having the sheet number i of 1 in the reference chart BC.

  In step S420 (FIG. 8), the color measurement date adding unit 242 (see FIG. 1) in the color measurement processing unit 240 adds the color measurement date to the color measurement value file MF. The color measurement date adding unit 242 refers to the current date output from the timer 150 (see FIG. 1) during or after the color measurement processing by the color measurement processing unit 240, for example, the color measurement date as text data Is added to the colorimetric value file MF. The color measurement value file MF shown in FIG. 9 shows a state in which a color measurement date is added.

  In step S430 (FIG. 8), the imaging processing unit 250 (see FIG. 1) images the reference chart BC and generates a reference input value file BIF. FIG. 3 shows a state in which the reference chart BC is imaged and the reference input value file BIF is generated. FIG. 10 is an explanatory diagram showing an example of the reference input value file BIF. The imaging processing unit 250 captures N sheets of the reference chart BC, and acquires an R value that represents the gradation value of the R component as an image input value at the position of the 24 patches in each sheet. For example, the first and second lines of the reference input value file BIF shown in FIG. 10 indicate the R values of 24 patches in the sheet having the sheet number i of 1 in the reference chart BC. In this embodiment, the R value is used as the image input value of the reference chart BC. However, for example, other image input values such as a G value and a B value can be used.

  In step S440 (FIG. 8), the date input / addition unit 252 (see FIG. 1) in the imaging processing unit 250 adds the production date of the reference chart BC to the reference input value file BIF. The date input / addition unit 252 has an OCR function for optically reading printed characters. The date input / addition unit 252 reads the reference chart BC production date printed on each sheet of the reference chart BC and stores it in the reference input value file BIF. Append. The reference input value file BIF shown in FIG. 10 shows a state in which the reference chart BC production date is added.

  In step S450 (FIG. 8), the elapsed days determination unit 230 (see FIG. 1) determines the elapsed days from the colorimetric date. The determination of the number of days elapsed from the color measurement date is performed to determine whether or not the color measurement value file MF used for generating the LUT file is correct. As described above, since the LUT file is updated every 30 days, for example, the LUT file generation process shown in FIG. 8 is repeatedly executed every 30 days. Therefore, there is a possibility that the old colorimetric value file MF generated in the previous LUT file generation process is erroneously used in the new LUT file generation process. In this embodiment, in order to prevent misuse of the old colorimetric value file MF, the number of days elapsed from the colorimetric date is determined.

  For example, specifically, the elapsed days from the color measurement date is determined by the elapsed date determination unit 230 from the current date output from the timer 150 (see FIG. 1) and the color measurement date included in the color measurement value file MF. (See FIG. 9), and by determining whether the number of days elapsed from the color measurement date to the present is within 5 days. That is, if the number of days elapsed from the color measurement date to the present is within 5 days, it is determined that the color measurement value file MF is correct. If the number of elapsed days is 6 days or more, the color measurement value file MF is old. It is determined to be a thing. Note that the determination threshold may be less than the LUT file update cycle, and the threshold may be set shorter or longer. For example, if all the steps of the LUT file generation process shown in FIG. 8 are necessarily performed on the same day, the threshold value may be set to one day.

  In the determination of the number of days elapsed from the color measurement date in step S450 (FIG. 8), when it is determined that the number of elapsed days is 6 days or more, the process is terminated and the color measurement value file MF is confirmed. On the other hand, when it is determined that the number of elapsed days is within 5 days, the process proceeds to step S460.

  In step S460 (FIG. 8), the elapsed days determination unit 230 (see FIG. 1) determines the elapsed days from the reference chart BC production date. To determine the number of days elapsed from the date of creation of the reference chart BC, whether or not the reference input value file BIF used to generate the LUT file is correct, and consequently the reference chart BC used to generate the reference input value file BIF is correct. This is to determine whether or not there has been. As described above, since the reference chart BC is updated, for example, every 90 days, the old reference chart BC may be erroneously used when the reference input value file BIF is generated. In this embodiment, in order to prevent misuse of the old reference chart BC, the number of days elapsed from the reference chart BC production date is determined.

  For example, specifically, the elapsed days determination from the reference chart BC creation date is performed by the elapsed day determination unit 230 including the current date output from the timer 150 (see FIG. 1) and the reference included in the reference input value file BIF. This is done by comparing the chart BC production date and determining whether the number of days elapsed from the reference chart BC production date to the present date is within 95 days. That is, if the number of days elapsed from the creation date of the reference chart BC to the present is within 95 days, it is determined that the reference chart BC used to generate the reference input value file BIF is correct, and the elapsed days are 96 days or more. If so, it is determined that the reference chart BC used to generate the reference input value file BIF is old. Note that the determination threshold may be equal to or longer than the update period of the reference chart BC and less than twice the update period of the reference chart BC, and may be set shorter or longer. I do not care. For example, the threshold value may be set to 90 days.

  If it is determined in step S460 (FIG. 8) that the number of days elapsed from the reference chart BC production date is 96 days or more, the process is terminated and the reference input value file BIF is confirmed. On the other hand, when it is determined that the number of elapsed days is within 95 days, the process proceeds to step S470.

  In step S470 (FIG. 8), the LUT generation unit 210 (see FIG. 1) generates an LUT file using the colorimetric value file MF and the reference input value file BIF. FIG. 3 shows how a LUT file is generated using the colorimetric value file MF and the reference input value file BIF. FIG. 11 is an explanatory diagram showing an example of an LUT file. FIG. 11A shows details of the contents of the LUT file. As shown in FIG. 11A, the LUT file includes 24 LUTs (LUT-1 to LUT-24) corresponding to the 24 patches in each sheet in the reference chart BC. In the following description, the LUT corresponding to the patch with the patch number j is represented as LUT-j.

LUT-j is an image colorimetric value (L ^* value) in the colorimetric value file MF (see FIG. 9) and an image input value (R value) in the reference input value file BIF (see FIG. 9) for the patch with patch number j. 10), the number of sheets corresponding to the number of sheets of the reference chart BC is included. For example, in the LUT-1 corresponding to the patch whose patch number j is 1 shown at the top of FIG. 11A, the L ^* value of the patch whose patch number j is 1 in the colorimetric value file MF, The R value of the patch whose patch number j is 1 in the reference input value file BIF is associated with each sheet number i.

Here, each sheet in the reference chart BC is printed based on image data having different N types of gradation values G for patches having the same patch number j. Therefore, for example, the LUT-1 corresponding to the patch whose patch number j is 1 is the correspondence between the L ^* value and the R value for N types of patches printed based on image data having N types of gradation values. It represents. FIG. 11B shows this correspondence using a graph. As described above, the LUT-j associates the image input value at the predetermined position of the scanner 400 (the patch position of the patch number j) with the image colorimetric value of the colorimeter 300. As shown in FIG. 11B, when the LUT is actually used, the correspondence specified by the N patches is interpolated using, for example, linear interpolation.

  In step S480 (FIG. 8), the LUT generation date adding unit 212 (see FIG. 1) adds the generation date of the LUT file to the LUT file. The LUT generation date adding unit 212 refers to the current date output from the timer 150 (see FIG. 1) during or after generation of the LUT file by the LUT generation unit 210, for example, the LUT file generation date as text data, Append to LUT file. The LUT file shown in FIG. 11A shows a state in which the LUT file generation date is added. This LUT file corresponds to “conversion data” in the claims.

  After the LUT file preparation in step S300 (see FIG. 2) is completed, the scanner 400 (see FIG. 1) is inspected in step S360. In principle, the inspection of the scanner 400 in step S360 is performed once every 24 hours. Note that the scanner 400 may not be checked on Saturday and Sunday. The relationship between the scanner inspection interval T1, the LUT file update interval T2, and the reference chart BC update interval T3 is preferably T1 <T2 <T3.

FIG. 12 is a flowchart showing a flow of inspection processing of the scanner 400. FIG. 13 is a diagram illustrating data created when the scanner 400 is inspected. In step S362 of FIG. 12, the colorimetric processing unit 240 (see FIG. 1) controls the colorimeter 300 to measure the color of the check chart CC and generates a colorimetric value file CMF (see the upper left of FIG. 13). Here, it is assumed that the inspection chart CC is the reference chart BC-M having the center sheet number among the N reference charts BC (see FIG. 3). The colorimetric processing unit 240 measures the 24 patches of the inspection chart CC and acquires the value of L ^* as the image colorimetric value for each patch. The L ^* value for each patch corresponds to the “reference colorimetric value” referred to in the claims.

  In step S364, the imaging processing unit 250 (see FIG. 1) images the inspection chart CC and generates an inspection input value file CIF1 (see the upper right in FIG. 13). The imaging processing unit 250 images the inspection chart CC and acquires an R value that represents the gradation value of the R component as an image input value at the positions of 24 patches in the sheet. This R value corresponds to an “inspection input value” in the claims. In this embodiment, the R value is used as the image input value of the inspection chart CC. However, other image input values such as gradation values of other color components, for example, G value and B value may be used. Is possible.

  In step S364, the imaging processing unit 250 stores the time when the inspection chart CC is captured in the inspection input value file CIF1. The imaging processing unit 250 refers to the current time output from the timer 150 (see FIG. 1) during or after the imaging process, and stores, for example, the imaging time as text data in the inspection input value file CIF1. The stored colorimetric time includes date information. Hereinafter, the imaging time of the inspection chart CC is referred to as “scanner inspection time”. The inspection input value file CIF1 shown in FIG. 13 shows a state where the scanner inspection time is added.

In step S366, the input value conversion unit 222 (see FIG. 1) of the print adjustment amount setting unit 220 converts the image input value (R value) in the inspection input value file CIF1 into an L ^* value using the LUT file. The inspection input value file CIF2 is generated (see the lower right in FIG. 13). This L ^* value corresponds to an “inspection colorimetric value” in the claims. The contents of the process of converting the R value into the L ^* value are the same as when the sample conversion file SCF is generated from the sample input value file SIF using the LUT file (see FIG. 4). This process will be described later.

In step S368, the imaging inspection unit 270 (see FIG. 1) compares the L ^* values of the corresponding patches in the colorimetric value file CMF and the inspection input value file CIF2, and the difference ΔL ^* between them is within a predetermined value Th. It is determined whether or not. For example, the predetermined value Th can be a value 1 of L ^* in the L ^* a ^* b ^* color system. However, the predetermined value Th may be any value between 0.8 and 1.2. However, the predetermined value Th is more preferably a value within the range of 0.9 to 1.1. Of L ^* value of each patch of inspection input value file CIF2, when the magnitude of the deviation from the L ^* value of the corresponding colorimetric value file CMF there is more than the predetermined value Th, the imaging inspection unit 270 In step S370, as shown in the lower part of FIG. 13, a warning such as “the scanner measurement value is abnormal” is displayed on the display 120 of the computer 100 (see FIG. 1), and the process ends.

  When a warning is displayed on the display 120 of the computer 100, the user checks the dirt on the reading surface of the scanner 400, checks whether the lamp is burned out, etc. The cause of the abnormality can be confirmed and removed. In addition, it is possible to confirm whether the inspection chart CC is dirty. If no abnormality is found, the LUT file is recreated (see step S300 in FIG. 2). Therefore, with such an aspect, it is possible to prevent a situation in which the adjustment amount B of the printer 500t is set in step S500 (see FIG. 2) as it is when the scanner may generate an abnormal input value. .

  On the other hand, when the determination result is Yes in step S368, the imaging inspection unit 270 displays “scanner inspection end” or the like on the display 120, and reads the information on the scanner inspection time in the inspection input value file CIF2. And stored as inspection data in the external storage device 140 (see the lower left in FIG. 13). That is, the inspection data is data including the scanner inspection time. When the inspection data already exists in the external storage device 140, the imaging inspection unit 270 updates the inspection data. As a result, the scanner inspection time is updated. As described above, since the inspection of the scanner 400 is performed once in 24 hours, the inspection data and the scanner inspection time are updated in 23 to 25 hours if the inspection of the scanner 400 is properly performed. Thereafter, the process proceeds to step S500 in FIG.

  After the inspection of the scanner 400 is completed in step S360 (see FIG. 2), the print adjustment amount setting unit 220 (see FIG. 1) sets the adjustment amount B in step S500. The adjustment amount B is set for each printer on the production line.

  FIG. 14 is a flowchart showing the flow of the adjustment amount B setting process. In step S505, the elapsed day determination unit 230 (see FIG. 1) reads the scanner inspection time from the inspection data in the external storage device 140, and determines the elapsed time from the scanner inspection time. As described above, the periodic inspection of the scanner 400 should be performed, for example, every 24 hours. In this embodiment, it is possible to prevent a situation in which the adjustment amount of the printer 500t is set using the scanner 400 in a state where the regular inspection of the scanner 400 is not performed within a predetermined time from the current time. Therefore, in step S505, the elapsed time from the scanner inspection time is determined.

Specifically, age determination unit 230, in step S 505, compares the current time outputted from the timer 150 (see FIG. 1), a scanner inspection time included in inspection data, the scanner inspection time It is determined whether the elapsed time up to the present is within 30 hours. If the elapsed time from the scanner inspection time to the present time is less than 30 hours, it is determined that the scanner 400 has been properly subjected to periodic inspection. If the elapsed time is 30 hours or more, the scanner 400 properly performs periodic inspection. It is determined that it has not been received. In addition, it is preferable that the threshold value for the determination is equal to or more than the time interval for performing the periodic inspection and less than twice the time interval for performing the periodic inspection. However, the threshold value may be set shorter or longer. For example, if the periodic inspection of the scanner 400 is always performed within 25 hours, the threshold value may be set to 25 hours.

  If it is determined in step S505 that the elapsed time is 30 hours or more, the print adjustment amount setting unit 220 displays a warning such as “cancel adjustment amount setting” on the display 120 of the computer 100 in step S507. The processing is terminated (see the upper right in FIG. 4). On the other hand, when it is determined that the elapsed time is less than 30 hours, “adjustment amount setting start” or the like is displayed on the display 120 (see the upper left in FIG. 4), and the process proceeds to step S510.

  In step S510, the user prints the sample chart SC using the printer 500t that is the target of the print adjustment amount setting process. FIG. 4 shows how the sample chart SC is printed using the printer 500t. Here, the sample chart SC is a chart having the same pattern as the reference chart BC shown in FIG. 6, and 24 patches having different ink nozzles, dot diameters, and printing modes used for printing were printed using black ink. Is. However, the sample chart SC is composed of only one sheet. Here, if the gradation value of the image data used for printing the patch with the patch number j in the sample chart SC is expressed as “sample gradation value GSj”, the sample gradation value GSj is expressed by the following equation (1). Is set to satisfy. As described above, G1j is the gradation value of the image data used for printing the patch with the patch number j in the first sheet of the reference chart BC, and GNj is in the Nth sheet of the reference chart BC. Is the gradation value of the image data used for printing the patch with patch number j.

  G1j <GSj <GNj (1)

  This sample gradation value GSj corresponds to a “sample color designation value” in the claims.

  In step S520 (FIG. 14), the imaging processing unit 250 (see FIG. 1) images the sample chart SC and generates a sample input value file SIF. FIG. 4 shows a state in which the sample chart SC is imaged and a sample input value file SIF is generated. The imaging processing unit 250 acquires an R value that represents the gradation value of the R component as an image input value at the position of 24 patches in the sample chart SC. In the generated sample input value file SIF, the R value at the patch position of each patch number in the sample chart SC is represented in the same manner as the reference input value file BIF shown in FIG. This R value corresponds to the “target input value” in the claims.

  In step S530 (FIG. 14), the elapsed day determination unit 230 (see FIG. 1) determines the elapsed days from the LUT file generation date. The determination of the number of days elapsed from the LUT file generation date is performed in order to determine whether or not the LUT file used for the adjustment amount B setting process is correct. As described above, since the LUT file is generated every 30 days, the old LUT file generated before may be erroneously used in the adjustment amount B setting process. In this embodiment, in order to prevent misuse of this old LUT file, the number of days elapsed from the LUT file generation date is determined.

  For example, specifically, the elapsed days determination from the LUT file generation date is performed by the elapsed day determination unit 230 including the current date output from the timer 150 (see FIG. 1) and the LUT file generation date included in the LUT file ( 11) to determine whether the number of days elapsed from the LUT file generation date to the present is within 35 days. That is, if the number of days elapsed from the LUT file generation date to the present is within 35 days, the LUT file is determined to be correct, and if the number of days elapsed is 36 days or more, the LUT file is determined to be old. Is done. Note that the determination threshold may be longer than the LUT file update cycle and less than twice the LUT file update cycle, and may be set shorter or longer. . For example, the threshold value may be set to 30 days.

  In the determination of the number of days elapsed from the LUT file generation date in step S530 in FIG. 14, when it is determined that the number of days elapsed is 36 days or more, the process is terminated and the LUT file is confirmed. On the other hand, when it is determined that the number of elapsed days is within 35 days, the process proceeds to step S540.

In step S540 (FIG. 14), the input value conversion unit 222 (see FIG. 1) of the print adjustment amount setting unit 220 uses the LUT file to convert the image input value (R value) in the sample input value file SIF to L ^*. A sample conversion file SCF converted into values is generated. FIG. 4 shows how the sample conversion file SCF is generated from the sample input value file SIF using the LUT file.

Specifically, the input value conversion unit 222 converts the R value of the patch with the patch number in the sample input value file SIF into an L ^* value using the LUT corresponding to each patch number. For example, the R value of the patch whose patch number j is 1 in the sample input value file SIF is converted to L ^* using LUT-1 (FIG. 11B) corresponding to patch number 1. By using the 24 LUTs (LUT-1 to LUT-24) included in the LUT file, all the R values of the 24 patches in the sample input value file SIF can be converted into L ^* values. In the generated sample conversion file SCF, the L ^* values in the patches having the respective patch numbers in the sample chart SC are represented in the same manner as the colorimetric value file MF shown in FIG. This L ^* value corresponds to the “target colorimetric value” in the claims.

In step S550 (FIG. 14), the print adjustment amount setting unit 220 (see FIG. 1) calculates an ideal gradation value GI for each L ^* value in the sample conversion file SCF using the ideal relationship IR. FIG. 15 is an explanatory diagram schematically showing the ideal relationship IR. As shown in FIG. 15, the ideal relationship IR indicates a relationship between a gradation value G of image data used for printing a patch and a desired L ^* value of the patch in advance when the patch is printed using black ink. Defined. In other words, if the relationship between the tone value G and the L ^* value of the patch is on the curve of the ideal relationship IR, it is a desirable print characteristic. This ideal relationship IR corresponds to “color reproduction target data” in the claims.

Further, L ^* the ideal grayscale value GI for a value, which means the gradation value G on ideal relationship IR curve corresponding to a L ^* value. In other words, when a patch of lightness L ^* is to be printed on an ideal printer, the gradation value to be instructed to the ideal printer is determined by the ideal relationship IR curve and the ideal gradation determined by the L ^* value. The value GI. Therefore, calculating the ideal gradation value GI for each L ^* value in the sample conversion file SCF (see FIG. 4) means that the brightness of the print result is the value in the sample conversion file SCF when an ideal printer is used. This means that each gradation value G of the image data that becomes the L ^* value is calculated. Note that the ideal gradation value GI for the L ^* value of the patch with the patch number j in the sample conversion file SCF is represented as an ideal gradation value GIj. The ideal gradation value GIj corresponds to an “ideal designated value” in the claims.

  In step S560 (FIG. 14), the print adjustment amount setting unit 220 (see FIG. 1) sets the adjustment amount B. The adjustment amount B is a coefficient for multiplying the gradation value of the image data used for printing so that a desired printing result can be obtained in the target printer 500t. The adjustment amount Bj corresponding to the patch with the patch number j in the sample conversion file SCF is calculated by the following equation (2).

  Adjustment amount Bj = (sample gradation value GSj) / (ideal gradation value GIj) (2)

Since the adjustment amount B is set corresponding to the L ^* value of each patch, a total of 24 adjustment amounts B (B1 to B24) are set. Each of the 24 adjustment amounts B corresponds to a combination of the ink nozzle, the dot diameter, and the printing mode used for printing the corresponding patch in the sample chart SC. The adjustment amount B set as described above is stored as adjustment amount data BF in a predetermined storage area of the target printer 500t.

When printing is performed using a combination of nozzles, dot diameters, and the like when printing the patch j, adjustment is performed by multiplying the gradation value of the pixel in the image data used for printing by the corresponding adjustment amount Bj. For example, when the gradation value GIj is designated for a certain pixel, the gradation value GIj is multiplied by the adjustment amount Bj and replaced with GSj. As a result, the printer 500t reproduces the color whose brightness is the L ^* value based on the replaced gradation value GSj. With respect to the relationship between the gradation value of the input image data and the printing result, a color having a lightness L ^* value is reproduced for a pixel for which the gradation value GIj is designated in the image data. Therefore, when the gradation value GIj is designated for a certain pixel, the printer 500t performs printing similar to an ideal printer.

  Note that, in the case where a gradation value other than the gradation value GIj is designated for the pixels in the image data, adjustment is similarly performed by multiplying the gradation value by the adjustment amount Bj. Based on the image data adjusted in this way, the printer 500t performs the subsequent printing process. As a result, the printer 500t can perform printing similar to an ideal printer.

  As described above, according to the image processing system 10 of the present embodiment, the association between the image input value by the scanner 400 and the image colorimetric value by the colorimeter 300 is executed by generating an LUT file. Can do. The adjustment value B can be set using the scanner 400 so that the printer 500t can perform printing similar to an ideal printer.

Further, in the image processing system 10 of the present embodiment, the inspection chart CC is imaged by the scanner 400 every predetermined period, for example, every 24 hours. Then, the gradation value of the color component scanner 400 generates a value of data obtained from (R value) (L ^* value) is the value of the data obtained by colorimetry at a colorimeter (L ^* value) relative to Then, it is determined whether it is within a predetermined range (see step S368 in FIG. 12). If the gradation value is outside the predetermined range, a warning is displayed on the display 120 of the computer 100. For this reason, it is possible to prevent a situation in which the adjustment value of the printer is set by using a scanner whose generated input value is abnormal. Therefore, the adjustment value of the printer can be accurately set even if a scanner whose performance is likely to change with time as compared with the colorimeter is used. In addition, if a scanner is used, data can be obtained for a plurality of print results (patches) at a time, so that printer adjustment values can be set in a short time for a plurality of print modes.

  Further, in the image processing system 10 of the present embodiment, it is confirmed whether or not the periodic inspection of the scanner 400 is performed within a predetermined time prior to setting the adjustment amount for the printer 500t flowing on the production line (FIG. 14 step S505). If the periodic inspection is not performed within a predetermined time, a warning is displayed (step S507). For this reason, even if the image reading table of the scanner becomes dirty or the lamp of the image reading table is burned out within 24 hours, for example within 24 hours, the correct output value cannot be output. It is possible to prevent a situation in which the adjustment value of the printer is set using the scanner in such a state.

  The scanner reads an image in an area wider than that of the colorimeter on the image reading table. Further, in many cases, reading is performed by placing a reading target such as a sample chart SC on an image reading table installed horizontally. Therefore, the possibility that the image reading table becomes dirty and the reflected light to be read does not accurately reach the sensor is much higher than the possibility that the reading unit of the colorimeter becomes dirty. Therefore, as in this embodiment, prior to setting the adjustment amount of the printer, checking whether the periodic inspection is performed within a predetermined time is to set the adjustment value of the printer using the scanner. This is particularly effective when

  Further, in the image processing system 10 of this embodiment, when the LUT file is generated, the number of days elapsed from the color measurement date by the colorimeter 300 (step 450 in FIG. 8) and the number of days elapsed from the reference chart BC production date. Determination (step S460 in FIG. 8) is performed. Therefore, misuse of the colorimetric value file MF and misuse of the reference input value file BIF can be prevented. Further, in the image processing system 10 of the present embodiment, when the LUT file is used, the number of days elapsed from the LUT file generation date is determined (step S530 in FIG. 14). Therefore, misuse of the LUT file can be prevented. Therefore, according to the image processing system 10 of the present embodiment, the image input value by the scanner 400 and the image colorimetric value by the colorimeter 300 can be associated efficiently and accurately.

  In the image processing system 10 of the present embodiment, the adjustment amount setting process of the printer 500t that performs printing using four colors of ink can be performed using only one color of black ink, and the print adjustment amount setting process is performed. Can be done efficiently.

C. Variations:
The present invention is not limited to the above-described examples and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

C1. Modification 1:
In the above embodiment, among the L ^* value of each patch of inspection input value file CIF2, deviation from the L ^* value of the corresponding colorimetric value file CMF based on whether there is more than a predetermined value, the scanner It was determined whether or not to update the inspection time (step S368 in FIG. 12). However, whether or not to update the scanner check time may be determined by another method. For example, among the ^{L *} value of each patch of inspection input value file CIF2 (FIG. 13), the corresponding patch colorimetric value file MF reference chart BC-M (i.e., inspection charts CC) (FIG. 3) ^{L *} You may determine based on whether the magnitude | size of deviation | shift from a value was beyond a predetermined value. That is, it can be determined based on whether or not the inspection colorimetric value (L ^* value) of each patch in the inspection input value file CIF2 is within a predetermined range.

  Whether or not to update the inspection time of the scanner may be determined as follows. For example, among the R values of each patch in the inspection input value file CIF1 (FIG. 13), the R value of the corresponding patch in the reference chart BC-M (ie, the inspection chart CC) in the reference input value file BIF (FIG. 3). It may be determined based on whether or not there is a deviation of a predetermined value or more. That is, it can be determined based on whether or not the input value of each patch in the inspection input value file CIF1 is within a predetermined range including the input value (R value) of the corresponding patch in the reference chart BC-M. .

C2. Modification 2:
In the above embodiment, the scanner as the image input device reads the target color, and uses the R value, G value, and B as evaluation values of the red, green, and blue components as input values representing the characteristics of the color. The value could be output. However, the image input device may be, for example, a device that can read the target color and output any of the R value, the G value, and the B value, or can output only the brightness. In other words, the image input device only needs to be able to read the color of the target portion and generate a value representing the color characteristic. As the image input device, for example, a digital still camera may be employed in addition to the scanner.

C3. Modification 3:
In the above embodiment, a warning issued when there is an abnormality in the periodic inspection of the scanner is displayed on the display 120 of the computer 100 (see the lower left in FIG. 13). Further, when setting the adjustment amount of the printing apparatus, a warning issued when the elapsed time from the scanner inspection time exceeds the reference is also displayed on the display 120 of the computer 100 (see the upper right in FIG. 4). However, these warnings may be made in other ways. For example, a voice warning may be issued, or a lamp may be turned on to issue a warning. That is, the warning may be any warning that prompts the user to stop the acquisition of the colorimetric value by the image input device or the setting of the adjustment amount of the printing device.

C4. Modification 4:
In the above embodiment, the inspection time of the image input apparatus (scanner 400) referred to before setting the adjustment value of the printing apparatus is the imaging time of the inspection chart CC (see the upper right in FIG. 13). However, the inspection time of the image input device can be another time. For example, it is confirmed that there is no significant change in the performance of the image input device, and as a result, the time when the inspection data is stored in the external storage device 140 can be set (see the lower left in FIG. 13). That is, the data on the inspection time of the image input device may be any data that substantially represents the time at which the process (see FIG. 14) at any stage of the inspection processing of the image input device is performed. Further, the inspection time data may be stored in a format other than the date and the hour and minute.

C5. Modification 5:
In the above embodiment, the image processing system 10 is used for setting the adjustment amount B of the printer. However, the image processing system 10 corresponds to the correspondence between the image input value by the image input device and the image colorimetric value by the colorimeter. It can be used for other purposes as long as it is attached.

C6. Modification 6:
In the above embodiment, the elapsed days determination unit 230 of the image processing system 10 determines the elapsed days from the colorimetric date, the elapsed days from the reference chart BC production date, the elapsed days from the LUT file generation date, The determination of the elapsed time from the scanner inspection time is performed, but it is not always necessary to perform all of these four determinations, and any determination may be made as long as the elapsed time from the scanner inspection time is determined.

C7. Modification 7:
The reference chart BC and the sample chart SC used in the above embodiment are merely examples, and other charts can be used. For example, in the above-described embodiment, the sample chart SC is a single sheet printed with black ink using 24 patches that are different from each other in ink nozzle, dot diameter, and print mode (resolution) used for printing. there were. However, the sample chart SC is, for example, a patch having the same ink nozzle, dot diameter, and printing mode (resolution), and printed by printing methods with different relative feeding methods between the printing head of the printing apparatus and the printing medium. May be included. That is, the sample chart SC only needs to include patches printed by different methods using the printing apparatus. If at least one of the ink nozzle used for printing, the dot diameter, the printing mode (resolution), and the relative feeding method between the print head and the printing medium is different, it corresponds to “different method”. Shall. Further, the sample chart SC may include a plurality of patches that are printed based on color designation values that designate colors with different brightness.

  In the above embodiment, the reference chart BC and the sample chart SC are all printed using only one black ink, but cyan, magenta, yellow, light cyan, and light magenta that are originally used for the ink nozzles of the printer. You may print using ink, such as.

  In the above embodiment, the patches whose colors are read by the scanner 400 or the colorimeter when the LUT file is generated or when the scanner 400 is inspected are areas separated from each other. However, the areas read in those cases may be in contact with each other. That is, the area where the color is read by the scanner 400 or the colorimeter when the LUT file is generated or the scanner 400 is inspected may be a single color area having a single color. It is assumed that the “single color” includes an achromatic color, and the achromatic colors having different brightness values are not “a single color”.

C8. Modification 8:
The configuration of the image processing system 10 in the above embodiment is merely an example, and the image processing system 10 can have other configurations. For example, the image processing system 10 may include a digital camera instead of the scanner 400 as an image input device. In this embodiment, as the printer 500 of the image processing system 10, an ink jet printer using inks of four colors C, M, Y, and K is used. For example, LC (light cyan), LM (light It is also possible to use other printers such as an ink jet printer using six colors of ink including two colors (magenta) and a printer other than the ink jet printer.

1 is an explanatory diagram schematically showing the configuration of an image processing system as a first embodiment of the present invention. FIG. 6 is a flowchart illustrating a flow of print adjustment amount setting processing by the image processing system according to the present exemplary embodiment. FIG. 5 is an explanatory diagram showing an overview of processing for preparing a reference chart BC and processing for preparing an LUT file in the print adjustment amount setting processing. FIG. 4 is an explanatory diagram showing an outline of adjustment amount B setting processing in print adjustment amount setting processing. The flowchart which shows the flow of a preparation process of reference | standard chart BC. Explanatory drawing which shows the content of reference | standard chart BC roughly. The flowchart which shows the flow of a process of preparation of a LUT file. 8 is a flowchart showing a flow of LUT file generation processing in step S400 of FIG. Explanatory drawing which shows an example of the colorimetric value file MF. Explanatory drawing which shows an example of the reference | standard input value file BIF. Explanatory drawing which shows an example of a LUT file. 6 is a flowchart showing a flow of inspection processing of the scanner 400. The figure which shows the data produced in the case of the inspection of the scanner 400. FIG. The flowchart which shows the flow of a process of adjustment amount B setting. Explanatory drawing which shows ideal relationship IR roughly.

Explanation of symbols

10. Image processing system 100 ... Computer 110 ... CPU
120 ... display part (display)
130 ... Operation unit 140 ... External storage device 150 ... Timer 160 ... Interface unit 170 ... Bus 200 ... Internal storage device 210 ... LUT generation unit 212 ... LUT generation date Additional unit 220 ... Print adjustment amount setting unit 222 ... Conversion unit 230 ... Elapsed days determination unit 240 ... Color measurement processing unit 242 ... Color measurement date addition unit 250 ... Imaging processing unit 252 ... Additional unit 260 ... Print processing unit 270 ... Imaging inspection unit 300 ... Colorimeter 400 ... Scanner 500,500t ... Printer B ... Adjustment amount BC ... Reference chart BF ... Adjustment amount data BIF ... Reference input value file Bj ... Adjustment amount CC ... Check chart CMF ... Colorimetric value file IR ... Ideal relationship MF ... Colorimetric value file SC ... Sample chart SCF ... Sample conversion file SIF ... Sample input value file i ... Sheet number j ... Patch number ΔL ^* ... L ^* value difference of corresponding patches in the colorimetric value file CMF and the inspection input value file CIF2

Claims (13)

A method of generating adjustment data for correcting printing characteristics of a printing apparatus using an image input apparatus capable of simultaneously reading the colors of a plurality of target parts and generating input values representing the color characteristics of the target parts. There,
(A) The image input device is inspected using a colorimeter that has less change in performance over time than the image input device, and a predetermined condition indicating that the image input device functions normally is If the result of the inspection satisfies the generated inspection data including data of time inspection, if the result of the inspection does not satisfy the predetermined condition, the method comprising issuing a warning, repeat a process of execution ,
(B) After any one of the repeated processes, a plurality of patches printed by the printing apparatus using different methods are imaged by the image input apparatus, and Generating the adjustment data based on the input value representing a color characteristic,
The step (b)
(B1) obtaining an elapsed time from the time of the inspection in the inspection data;
(B2) issuing a warning when the elapsed time exceeds a predetermined period;
(B3) generating the adjustment data when the elapsed time is less than the predetermined period. The method of claim 1, further comprising:
(C) conversion data for storing a colorimetric value obtained by measuring a predetermined color with a colorimeter and an input value obtained by imaging the predetermined color with the image input device in association with each other. A preparation process;
(D) preparing a color reproduction target data for storing the colorimetric values of the colors to be reproduced by the printing apparatus when a color designation value for designating a predetermined series of colors is given,
The step (b3)
(B4) printing the patch with the printing device based on a sample color designation value that is a color designation value for designating a sample color included in the predetermined series;
(B5) capturing the patch with the image input device to obtain a target input value that is an input value corresponding to the patch;
(B6) using the conversion data, converting the target input value into a target colorimetric value that is a colorimetric value corresponding to the patch;
(B7) using the color reproduction target data, converting the target colorimetric value into an ideal designated value that is a color designated value corresponding to the patch;
(B8) generating the adjustment data based on the sample color designation value and the ideal designation value. The method of claim 2, comprising:
The colorimetric value is the value of L ^* in the L ^* a ^* b ^* color system, method. The method of claim 3, comprising:
The predetermined series of colors are achromatic colors having different brightness from each other,
The step (b4) includes a step of printing the patch using black ink in the printing apparatus based on the sample color designation value. The method of claim 1, further comprising:
The step (a)
Imaging a predetermined inspection patch with the image input device to obtain an inspection input value that is an input value corresponding to the inspection patch;
The predetermined condition is that the inspection input value is within a predetermined range. The method of claim 1, further comprising:
(C) conversion data for storing a colorimetric value obtained by measuring a predetermined color with a colorimeter and an input value obtained by imaging the predetermined color with the image input device in association with each other. With a process of preparation,
The step (a)
(A1) measuring a predetermined inspection patch with the colorimeter to obtain a reference colorimetric value that is a colorimetric value corresponding to the inspection patch;
(A2) imaging the inspection patch with the image input device to obtain an inspection input value that is an input value corresponding to the inspection patch;
(A3) using the conversion data, converting the inspection input value to an inspection colorimetric value that is a colorimetric value corresponding to the inspection patch,
The predetermined condition is that the inspection color measurement value and the reference color measurement value are closer to a predetermined reference. The method of claim 6, comprising:
The colorimetric value is the value of L ^* in the L ^* a ^* b ^* color system, method. The method of claim 7, comprising:
The method, wherein the inspection patch is an achromatic patch. A method according to any of claims 1 to 8, comprising
The method, wherein the input value is a gradation value of a red, green or blue color component. A method of manufacturing a printing apparatus,
Generating the adjustment data by the method according to claim 1;
Storing the adjustment data in a storage unit of the printing apparatus. A method for obtaining a colorimetric value of each target portion color by using an image input device capable of simultaneously reading the colors of a plurality of target portions and generating an input value representing a color characteristic of each target portion,
(A) The image input unit is inspected using a colorimeter that has less change in performance over time than the image input device, and a predetermined condition indicating that the image input device functions normally is satisfied. If the result of the inspection satisfies the steps of generating the inspection data, it repeats the process of execution representing the time of the inspection,
By imaging a plurality of target portions the image input device printed with (b) different methods, the based on the input value representing the color characteristics of each target portion, the color of the colorimetric each object parts Obtaining a value, and
The step (b)
(B1) obtaining an elapsed time from the time of the inspection in the latest inspection data;
And (b2) issuing a warning when the elapsed time exceeds a predetermined period. A system for generating adjustment data for correcting printing characteristics of a printing apparatus,
An image input unit capable of simultaneously reading the colors of a plurality of target portions and generating input values representing the color characteristics of the target portions;
The result of the inspection of the image input unit performed using a colorimeter having less change in performance over time than the image input unit satisfies a predetermined condition indicating that the image input unit functions normally. An imaging inspection unit that repeatedly executes a process of generating inspection data including data of the time of inspection when the condition is satisfied, and issuing a warning when the result of the inspection does not satisfy the predetermined condition;
After any one of the repeated processes, a plurality of patches printed by different methods using the printing apparatus are imaged by the image input unit, and the color characteristics of each patch A print adjustment amount setting unit that generates the adjustment data based on the input value representing:
An elapsed time determination unit for obtaining an elapsed time from the time of the inspection in the inspection data,
The print adjustment amount setting unit
When the elapsed time exceeds a predetermined period, a warning is issued,
The system that generates the adjustment data when the elapsed time is less than the predetermined period. A computer program for generating adjustment data for correcting printing characteristics of a printing apparatus using an image input apparatus capable of simultaneously reading the colors of a plurality of target parts and generating input values representing the color characteristics of the respective target parts Because
The result of the inspection of the image input device that is performed using a colorimeter with less change in performance over time than the image input device satisfies a predetermined condition indicating that the image input device functions normally. A function for repeatedly executing the process of generating inspection data including the data of the time of inspection when the condition is satisfied, and issuing a warning when the result of the inspection does not satisfy the predetermined condition;
After any one of the repetitively performed processes, a plurality of patches printed by the printing apparatus using different methods are imaged by the image input apparatus, and the color characteristics of each patch A function of generating the adjustment data based on the input value representing:
A function for obtaining an elapsed time from the time of the inspection in the inspection data;
A function for issuing a warning when the elapsed time exceeds a predetermined period;
A computer program that causes a computer to realize the function of generating the adjustment data when the elapsed time is less than the predetermined period.

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