JP2019213024A - Image processing apparatus and image processing method - Google Patents

Abstract

To provide an image processing apparatus that adjusts the color of an output image to the colors of a plurality of target prints when color reproduction differs from among the plurality of target prints due to variations in printers despite the same color from among a plurality of pages of print image data.SOLUTION: In an image formation system, an image processing apparatus 3 includes a print image data input unit that accepts an input of print image data composed of a plurality of pages, a target scan image input unit that receives an input of a scan image of a target print in which a target color to be reproduced of print image data is output, a color data association unit that associates the color data of the print image data with the color data of the scan image of the target print, and a color data comparison unit that specifies a location where the color data differs among the plurality of pages of the scan image in the color data of the plurality of pages of the scan image of the target print corresponding to the color data of the plurality of pages of the print image data even when the color data is the same from among the plurality of pages of the print image data.SELECTED DRAWING: Figure 6

Description

  The present invention relates to an image processing apparatus and an image processing method for matching an output image with a color sample color.

  Conventionally, after a customer confirms a color sample (target printed matter) such as a poster or a package, a printing machine performs a process (printing process) for forming an output image on a recording material based on the color sample. At that time, in order to match the output image of the printing press with the color of the color sample, a color conversion table is used by using a read image (hereinafter also referred to as a “scan image”) obtained by reading information on the surface of the color sample with a scanner. A fix has been made. For example, an ICC (International Color Consortium) profile is used as the color conversion table. In the ICC profile, conversion from a device-dependent color space such as the CMYK color system to a device-independent color space such as the L * a * b * color system (CMYK-L * a * b *), or a CMYK table Conversion from a color space of a color system to a color space of a CMYK color system (CMYK-CMYK) is defined.

  In general color conversion table editing, a combination of CMYK values and L * a * b * values in a color sample consisting of a plurality of pages due to variations in the printing press (intra-page unevenness, unevenness between pages, etc.). When there are a plurality of colors, it is impossible to perform color conversion that can achieve a plurality of color reproductions. For this reason, the colors of all points constituting the output image cannot be matched with a plurality of color samples.

  In order to solve such a problem, Patent Document 1 (see paragraph [0169] and the like) discloses that one average target profile is created from a plurality of target printed materials. Patent Document 1 states that “when creating an average target profile, a plurality of target prints include similar colors, and similar colors are extracted from read image data of the plurality of target prints. "When matching colors to grid points when creating a color conversion table, color matching occurs, and the corrected Lab point Lab value is the average value of a plurality of similar colors."

  Here, the prior art will be described with reference to FIG. As shown on the left side of FIG. 1, the print image data Im that is the original data of the target print CS (color sample) is, for example, a two-page PDF file (print image data Im1, Im2). The apples in the print image data Im1 of the first page and the print image data Im2 of the second page have substantially the same color Ap (for example, red and have the same CMYK value). The target printed matter CS has two pages and is composed of the target printed matter CS1 and the target printed matter CS2. The target prints CS1 and CS2 are generated based on the print image data Im1 and Im2, respectively. The apple colors in the target prints CS1 and CS2 are the colors Ap1 and Ap2, respectively. In the example of FIG. 1, the apple color Ap2 of the target print CS2 on the second page is red, similar to the apple color Ap of the corresponding print image data Im2, but the apple color of the target print CS1 on the first page. Ap1 is a yellowish color unlike the apple color Ap (red) of the corresponding print image data Im1.

  In general, in the correction of the color conversion table, first, a target printed matter is read (scanned) by a scanner, and a colorimetric value (for example, RGB value) output by the scanner is used as a color system of a device-independent color space (for example, L * a * B *). In the image processing apparatus, the color conversion table CP (for example, L * a * b * -CMYK) is corrected based on the colorimetric values of L * a * b *.

  As shown on the right side of FIG. 1, when the color conversion table CP is corrected in accordance with the target print CS1 of the first page, the first and second prints S1 generated based on the corrected color conversion table CP. , S2 is the color Ap1 (modified example (1)). Further, when the color conversion table CP is corrected in accordance with the target print CS2 of the second page, each apple of the first and second page prints S1, S2 generated based on the corrected color conversion table CP. Becomes the color Ap2 (modified example (2)). Further, when the color conversion table CP is corrected in accordance with the average of the target print CS1 on the first page and the target print CS2 on the second page, the first page and the second page generated based on the corrected color conversion table CP. Each apple of the printed matter S1, S2 has a color Ap12 (for example, an orangeish color) (Modification Example (3)). The modification example (3) corresponds to the technique described in Patent Document 1.

JP 2006-048900 A

  As described above, in the technique described in Patent Document 1, when similar colors (for example, CMYK values) exist in a plurality of color samples, color is calculated using an average value obtained from the colorimetric values of each color (measurement point). Create a conversion table. For this reason, even when a plurality of pages having different print image data have the same color, the output image (printed material S1, S2) is different when the color of the corresponding printed material is different due to variations in the printing press or the like. The color cannot be matched with the colors of the plurality of target prints (CS1, CS2).

  From the above situation, if there are multiple target prints with different color reproduction due to variations in the printing press, etc., despite the same color among multiple pages of print image data, the output image color is set to multiple target prints. The technique which can be matched with the color of was desired.

  An image processing apparatus according to an aspect of the present invention includes a print image data input unit that accepts input of print image data composed of a plurality of pages, and a scan image of a target printed matter from which a target color to be reproduced in the print image data is output. A scan image input unit that receives an input; a color data association unit that associates color data of print image data with color data of a scan image of a target print; Further, the image processing apparatus performs a comparison process using the color data of the print image data and the color data of the scan image of the target printed matter, and even if the color data is the same among a plurality of pages of the print image data, the print image A color data comparison unit that identifies locations where the color data differs among the plurality of pages of the scanned image in the color data of the plurality of pages of the scanned image of the target printed matter corresponding to the corresponding color data of the plurality of pages of data;

According to at least one aspect of the present invention, when there are a plurality of target prints having different color reproduction despite the same color among a plurality of pages of the print image data, the color of the output image is changed between the plurality of target prints. Can match the color.
Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

It is explanatory drawing which shows a prior art. It is explanatory drawing which shows the 1st effect by the image processing which concerns on one Embodiment of this invention. It is explanatory drawing which shows the 2nd effect by the image processing which concerns on one Embodiment of this invention. 1 is an explanatory diagram illustrating an example of an overall configuration of an image forming system according to an embodiment of the present invention. 1 is a block diagram illustrating a hardware configuration example of a computer included in each device that configures an image forming system according to an embodiment of the present disclosure. 1 is a block diagram illustrating an example of an internal configuration of each device that configures an image forming system according to an embodiment of the present disclosure. FIG. It is a flowchart which shows the example of a procedure of the image processing method which concerns on one Embodiment of this invention. It is explanatory drawing which shows an example of the screen which shows the color sample test result which concerns on one Embodiment of this invention. It is explanatory drawing which shows the flow of the color conversion process using a device profile. It is explanatory drawing which shows the flow of the color conversion process using a device link profile. FIG. 11A is an explanatory diagram showing an example of correcting an A2B table of a source profile in a device profile according to an embodiment of the present invention. FIG. 11A shows an A2B table before correction and FIG. 11B shows an A2B table after correction.

  Hereinafter, an example of a mode for carrying out the present invention (hereinafter referred to as “embodiment”) will be described with reference to the accompanying drawings. In the present specification and the accompanying drawings, components having substantially the same function or configuration are denoted by the same reference numerals, and redundant description is omitted.

[Overview of one embodiment]
One embodiment of the present invention relates to an image processing apparatus and an image processing method for correcting a color conversion table using scanned images of a plurality of target prints (color samples). In the present embodiment, an original (color, color, or the like) whose colorimetric values differ between pages of a printed matter due to printer fluctuations even though the original color (for example, CMYK values of print image data) is the same between pages. Position), and notify the user of the result. In the present embodiment, the color conversion table is switched for each page of the document, and output is performed with color reproduction according to the color sample on all pages.

  The target printed material is a color sample printed material of a target color to be reproduced, and is given as an actual color sample printed based on the print image data. The print image data is digital image data representing the content of the image to be printed. Any printer can be used as the output means for the target printed matter.

(First effect)
Next, effects of the image processing according to the present embodiment will be described. FIG. 2 is an explanatory diagram showing a first effect by the image processing according to the present embodiment. In the present embodiment, for example, information on whether or not colors can be matched with respect to two print targets and, if not, which color cannot be displayed, is displayed on the display device to notify the user. The following can be expected as the effect of the notification to the user (first effect).

  For example, the user can select means for (1) switching the color conversion table for each page of the print image data, or (2) correcting the print image data by the user. Based prints can be matched to multiple target prints. Further, when displaying the above contents on the display device, the user can check the color reproduction state before outputting to the recording material, so that useless output can be reduced.

  The example of FIG. 2 represents a state (GUI: Graphical User Interface) in which the scanned images of the target printed materials CS1 and CS2 (same as the upper left of FIG. 1) are displayed on the display device. Each scanned image of the target printed matter CS1, CS2 corresponds to a page that cannot be corrected by one color conversion table. In FIG. 2, the apple color Ap2 of the woman in the scan image of the second page (target print CS2) is compared with the apple color Ap1 of the man in the scan image of the first page (target print CS1). Since the color difference is large, a mark M is displayed on the corresponding apple to alert the user. In FIG. 2, the measured value (here, CMYK value) and the color difference (ΔE) with respect to the apple color on the first page are displayed as the color information CV of the apple color Ap2.

(Second effect)
FIG. 3 is an explanatory diagram showing a second effect by the image processing according to the present embodiment. As shown in FIG. 3, the target prints CS <b> 1 and CS <b> 2 are read by the scanner, and the colorimetric values (for example, RGB values) output by the scanner are represented by a color space system (for example, L * a * b *) in a device-independent color space. ). Then, in the client terminal 3 (see FIG. 6 described later), the color conversion table CP (see FIG. 1) is corrected (created) for each page based on the colorimetric values of L * a * b *. Here, the color conversion table CP1 is created by copying the color conversion table CP and converting the apple color Ap to the color Ap1 for the first page. Similarly, the color conversion table CP is copied to create the color conversion table CP2 for converting the apple color Ap to the color Ap2 for the second page. For example, the color conversion table CP may be directly corrected for the first page, and the copied color conversion table CP may be corrected (edited) for the second page.

  As described above, in this embodiment, the color conversion table can be duplicated only for the necessary pages of the print image data and the color conversion table corresponding to the corresponding page can be corrected (created). 2). That is, in the present embodiment, the color conversion table can be corrected only for pages where the print image data is necessary. Even when there are a plurality of target prints with different reproductions, all pages of the print image data can be reproduced in the color sample (color Ap1, color Ap2 in FIG. 3). Further, since the color conversion table is duplicated only for necessary pages, it is not necessary to create a color conversion table for every page.

[Overall configuration of image forming system]
Next, an image forming system (color adjustment system) according to the present embodiment will be described with reference to FIG. FIG. 4 shows an example of the overall configuration of the image forming system according to the present embodiment.

  An image forming system 10 shown in FIG. 4 includes a printer 1, a controller 2, a client terminal 3, and a scanner 4 (an example of a reading unit). The network 6 is a communication line such as a LAN (Local Area Network) conforming to a standard such as Ethernet (registered trademark). Each device is connected to be communicable with each other via the network 6.

  A printer 1 (an example of an image forming apparatus) is connected to a controller 2 via a communication interface, receives a print job (print image data and print settings) from the controller 2, and outputs print image data based on the print settings. Process. For example, the printer 1 forms (prints) an image on a sheet using three basic colors of cyan (C), magenta (M), yellow (Y) and black (K) having different hues.

  The printer 1 may be an electrophotographic printer, an ink jet printer, an offset printer, or the like, and may be of any format. Further, the target printed matter may be generated by any of the above printers. The term “printer” is understood as synonymous with terms such as a printing press, a printing apparatus, an image recording apparatus, an image forming apparatus, and an image output apparatus. Further, the printer 1 may be a multi-function peripheral (MFP) having a plurality of functions such as a print process, a copy function, and a scan function.

  The controller 2 receives a print job issued by the client terminal 3 via the network 6. Then, the controller 2 performs processing such as color conversion, screening, and rasterization on the print image data of the received print job, and transfers the print image data to the printer 1. The print image data is, for example, PDF data or TIFF data. Image data of a raster image for image formation is generated by rasterization (RIP) processing. Color conversion is performed using a color conversion table (lookup table). The printer 1 and the controller 2 may be connected by a dedicated line (PCI bus connection or the like).

  The client terminal 3 (an example of an image processing apparatus) issues a print job in response to a user input operation using a printer driver or dedicated software (application program), and transmits the print job to the controller 2. Give print instructions. In this embodiment, an application program capable of creating and correcting (editing) print image data is installed in the client terminal 3. As the client terminal 3, a general-purpose computer such as a PC (Personal Computer) is used. Further, the client terminal 3 receives a read image (hereinafter also referred to as “scanned image”) of the target printed matter output from the scanner 4 and corrects the color conversion table using the scanned image.

  The scanner 4 (an example of a reading unit) is used to read an output image of a color sample manually by a user. When the scanner 4 is set so that the printing surface of the output image of the color sample faces the reading surface, the scanner 4 reads the information (output image) on the surface of the color sample and transmits the reading result (scanned image) to the client terminal 3. To do.

  As the scanner 4, a line sensor in which a light emitting member and a plurality of photoelectric conversion elements are arranged at a predetermined interval in the paper width direction (direction orthogonal to the paper conveyance direction) or an image sensor in which photoelectric conversion elements are arranged in a matrix form is used. it can. Each photoelectric conversion element outputs a signal corresponding to the intensity of light emitted from the light source and reflected from the surface of the paper. As the line sensor and the image sensor, a CCD type sensor or a CMOS type (including MOS type) sensor can be used.

  The scanner 4 shown in FIG. 4 is a commercially available external scanner, but it may be a platen scanner attached to the printer 1, an automatic acquisition scanner installed in-line (paper transport path), or a digital still camera. May be used. As an example of the inline arrangement, there is a post-processing device connected to the downstream side of the fixing device in the printer 1 (after an image is formed on the paper) or the downstream side of the printer 1.

  Specifically, the scanner 4 spectrally measures each color included in the output image of the color sample, and transmits the measured colorimetric values of each color to the client terminal 3 as color data. Here, the colorimetric values obtained by the scanner 4 are spectral reflectance values (for example, RGB) and color system values that do not depend on devices such as XYZ and L * a * b * defined by the International Commission on Illumination (CIE). expressed. When the colorimetric value obtained by the scanner 4 is represented by a spectral reflectance value or an XYZ value, the client terminal 3 converts the colorimetric value into an L * a * b * value or a CIECAM02 value. It may be. In this embodiment, a case where RGB values are used as colorimetric values by the scanner 4 will be described.

  The controller 2 stores, for example, a color conversion table (device link profile) transmitted from the client terminal 3 or the network 6 in a storage device such as an HDD. The controller 2 can perform color conversion processing on the generated image data using a device link profile. The controller 2 transmits the image data that has been subjected to the color conversion process or not subjected to the color conversion process to the printer 1 for output.

  The controller 2 described above may be incorporated in the printer 1. Further, the function for correcting the color conversion table of the client terminal 3 may be built in the controller 2 or the printer 1.

[Hardware configuration of each device]
Next, the hardware configuration of the computer provided in the printer 1, the controller 2, and the client terminal 3 will be described. FIG. 5 is a block diagram illustrating a hardware configuration example of a computer.

  The computer 40 includes a CPU (Central Processing Unit) 41a, a ROM (Read Only Memory) 41b, and a RAM (Random Access Memory) 41c connected to a bus line 49, respectively. Further, the computer 40 includes a nonvolatile storage 42, a network I / F unit 43, an operation unit 44, and a display unit 45.

  The CPU 41a reads out the program code of software that implements each function included in the printer 1, the controller 2, and the client terminal 3 of the present embodiment from the ROM 41b and executes it. In the RAM 41c, variables, parameters, and the like generated during the arithmetic processing are temporarily written. The CPU 41a, ROM 41b, and RAM 41c constitute a control unit 41.

  For example, in the computer 40 constituting the printer 1, the CPU 41a reads a program stored in the ROM 41b, thereby performing control to form an image (print processing) on a sheet based on a print job.

  For example, in the computer 40 configuring the controller 2, the CPU 41a reads out a program stored in the ROM 41b, thereby performing control such as color conversion and rasterization processing for print image data of the print job.

  For example, in the computer 40 constituting the client terminal 3, the CPU 41a reads out a program stored in the ROM 41b, thereby creating and correcting (editing) print image data, and comparing the scanned image of the target print with the print image data. Control such as color matching determination and color conversion table correction is performed. When the print image data is corrected, the control unit 41 is used as an image correction unit. The image correction unit corrects the print image data in accordance with a user instruction to the operation unit 44 so that the color of the output image based on the print image data of the corresponding page matches the color of the target printed matter.

  As the nonvolatile storage 42, for example, a hard disk drive (HDD), a solid state drive (SSD), a flexible disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory, or the like is used. . In addition to the OS (Operating System) and various parameters, the nonvolatile storage 42 may store programs for causing the computer 40 to function as the printer 1, the controller 2, and the client terminal 3.

  The network I / F unit 43 is configured by, for example, a NIC (Network Interface Card) or the like, and transmits various data to and from a device connected via a LAN (Local Area Network) connected to a terminal or a dedicated line. Send and receive.

  For example, the network I / F unit 43 of the computer 40 configuring the controller 2 transmits a color conversion table to the client terminal 3 and receives a print job or a corrected color conversion table from the client terminal 3.

  For example, the network I / F unit 43 of the computer 40 configuring the client terminal 3 receives a color conversion table from the controller 2 and transmits a print job or a corrected color conversion table to the controller 2.

  The operation unit 44 includes, for example, keys and buttons, generates an operation signal according to the operation content input by the user, and supplies the operation signal to the CPU 41a. The display unit 45 is composed of a liquid crystal panel, for example, and displays characters, images, and the like on the screen. Depending on the configuration of the printer 1, the controller 2, or the client terminal 3, the operation unit 44 and the display unit 45 may not be provided.

[Example of internal configuration of each device]
Next, the internal configurations of the controller 2 and the client terminal 3 of the image forming system 10 will be described. FIG. 6 is a block diagram illustrating an internal configuration example of the controller 2 and the client terminal 3.

  The print engine 11 (an example of an image forming unit) of the printer 1 executes an image forming process in accordance with an instruction from the control unit 41 (see FIG. 5). Moreover, the function of each unit of the controller 2 shown in FIG. 6 is realized by the CPU 41a of the control unit 41 included in the controller 2 executing the program stored in the ROM 41b. Furthermore, the function of each unit of the client terminal 3 shown in FIG. 6 is realized by the CPU 41a of the control unit 41 included in the client terminal 3 executing the program stored in the ROM 41b.

(Example of the internal configuration of the controller)
The controller 2 is communicably connected to the print engine 11 and the client terminal 3, and includes a data input / output unit 21, a color conversion unit 22, a color conversion table setting unit 23, a color conversion table storage unit 24, and a RIP processing unit 25. Is provided.

  The data input / output unit 21 receives an input of a print job including print image data from a client terminal 3 which is an example of an information processing apparatus, and outputs a print job including print image data subjected to rasterization processing to the printer 1. . Further, the data input / output unit 21 receives the color conversion table CP from the client terminal 3 and stores it in the color conversion table storage unit 24.

  The color conversion unit 22 performs color conversion on the print image data included in the print job by using the color conversion table stored in the color conversion table storage unit 24, and the color converted print image data is subjected to RIP processing. To the unit 25. The color conversion table setting unit 23 sets a color conversion table to be applied for each page based on the print image data, reads the corresponding color conversion table, and supplies the color conversion table 22 to the color conversion table 22. The color conversion table storage unit 24 stores a default color conversion table CP and / or a modified color conversion table (for example, color conversion tables CP1 and CP2).

  For example, the RIP processing unit 25 performs rasterization processing on the color-converted print image data and supplies the rasterized processing to the data input / output unit 21.

(Example of internal configuration of client terminal)
The client terminal 3 is communicably connected to the controller 2 and is connected to an operation unit 44, a display unit 45, and a scanner 4. The client terminal 3 has interface functions such as reception of print image data, reception of a scanned image of a target print, display of color data comparison results, and registration of a color conversion table in the printer 1. The client terminal 3 includes a print image data input unit 31, a target printed material scan image input unit 32, a representative color extraction unit 33, an image position alignment unit 34, a color data comparison unit 35, a color matching determination unit 36, and a color conversion table correction. A unit 37 and a color conversion table registration unit 38.

  The print image data input unit 31 accepts input of print image data based on, for example, an operation signal input from the operation unit 44 and supplies the print image data to the representative color extraction unit 33. Further, the print image data input unit 31 may acquire print image data from the controller 2 via the network 6. The target printed product scanned image input unit 32 receives an input of the scanned image of the target printed product read by the scanner 4 and supplies the scanned image to the representative color extracting unit 33.

  The representative color extraction unit 33 and the image alignment unit 34 constitute a “color data association unit” that associates the color data of the print image data with the color data of the scan image of the target printed matter.

The representative color extraction unit 33 extracts a representative color for color matching from the print image data that is the original data of the target printed matter. As a method for extracting the representative color, for example, a cluster analysis method such as a K-average method can be used. The K-average method is a kind of non-hierarchical clustering algorithm, and is a method of classifying into k predetermined clusters using the average of clusters. In extracting representative colors, it is desirable to extract only points (regions) having a certain area. The certain degree is, for example, about 2 mm ² or more, which is a size that is hardly affected by general screen processing. The representative color may be extracted by limiting to a specific color or a color designated by the user.

  The image alignment unit 34 acquires color data corresponding to (corresponding to) the position of the representative color extracted from the print image data from the scanned image of the target printed matter. The color data of the scan image corresponding to the representative color of the print image data can be extracted by aligning the print image data and the scan image based on the image edge or image feature amount of the print image data. . The color data of the scanned image may be, for example, an RGB value based on the response value of the CCD. However, in order to evaluate the colorimetric value closer to the color difference perceived by humans, the colorimetric value (L * a * B *, CIEXYZ, CIECAM02, etc.) and it is desirable to evaluate the colorimetric values. In that case, a scanner profile in which the RGB values and colorimetric values of the scanner 4 are associated can be used. As the scanner profile, for example, a scanner profile in the ICC profile format can be used.

  The color data comparison unit 35 performs a comparison process using the color data of the print image data and the color data of the scan image of the target printed matter, and even if the color data is the same among a plurality of pages of the print image data, the print data In the color data of the plurality of pages of the scanned image of the target printed matter corresponding to the corresponding color data of the plurality of pages of the image data, the location where the color data differs among the plurality of pages of the scanned image of the target printed matter is specified. The function of the color data comparison unit 35 will be specifically described below.

  Specifically, the color data comparison unit 35 compares the color data of each representative color between pages of the print image data. Then, the color data comparison unit 35 searches for one or more representative colors (representative group) extracted by the representative color extraction unit 33 whether the same color (or substantially the same color) is used on a plurality of pages. . For example, the CMYK values of the second, third, and subsequent pages are searched for the CMYK value list of the representative color group on the first page of the print image data, and the CMYK values of the representative color group of the first page are searched. The same color in which the difference between the list and the searched CMYK value is equal to or less than a threshold (first threshold) is associated and temporarily stored in the RAM 41c. The first threshold value is a threshold value for determining whether or not the difference in color data between a plurality of pages of print image data is within a predetermined range. The color data comparison unit 35 performs this comparison process for the representative color group of all pages constituting the print image data.

  In addition, the color data comparison unit 35 uses the color of the plurality of pages of the scan image in the color data of the plurality of pages of the scan image of the target print corresponding to the representative color extracted as the same color among the plurality of pages of the print image data. It is determined whether or not the difference between the data exceeds a preset threshold (second threshold). The second threshold value is a threshold value for determining whether or not the difference in color data between a plurality of pages of the scanned image of the target printed matter is within a predetermined range.

  It is assumed that the first threshold value and the second threshold value are stored in advance in the ROM 41b or the nonvolatile storage 42. The control unit 41 (color data comparison unit 35) may be configured to set at least one of the first threshold value and the second threshold value based on the operation signal generated by the operation unit 44. The first threshold value and the second threshold value may be the same value, or may be set to different values.

  Further, the first threshold value and the second threshold value are generated by the operation unit 44 for each color data of the print image data or the scan image of the target printed matter, for each area formed by the color data, or for both. You may enable it to set based on an operation signal. Some users desire to output the color of human skin, company marks, logos, and the like on a printed material in a state closer to the target printed material. For example, when the area formed with the same color data (representative color) is large, the difference in color is conspicuous, so the first threshold value and the second threshold value (especially the second threshold value) may be set strictly.

  This determination may be made based on the RGB value distance in the RGB color space, which is the color space of the output color of the scanner 4, but is converted into a colorimetric value, particularly an L * a * b * value that is a uniform color space. Judgment based on the color difference from is preferable because it is suitable for human appearance. The color difference may be obtained using ΔE * ab which is a simple Euclidean distance between two L * a * b * values, or may be obtained using ΔE00 which is an improved color difference.

  Then, the color data comparison unit 35 has a color difference larger than the second threshold value between the color data of the plurality of pages of the scan image of the target print corresponding to the representative color of the plurality of pages of the print image data. Is determined, the corresponding color data of the scanned image is added as a color correction candidate to the color conversion table correction list 35a (see FIG. 8 for details). In FIG. 6, the color conversion table correction list is expressed as “correction list”.

  Further, the color data comparison unit 35 controls the display unit 45 to display the comparison result of the color data between a plurality of pages of the scanned image of the target printed matter. The color data comparison unit 35 also includes a plurality of pages of the scanned image of the target printed material in the color data of the plurality of pages of the scanned image of the target printed material corresponding to the same representative color among the plurality of pages of the printed image data. Control is performed so that information (see FIGS. 2 and 8) regarding the color data of the place where the color data is different is displayed on the display unit 45.

  The color matching determination unit 36 determines whether or not color matching can be performed on all pages of the print image data Im with one color conversion table CP with respect to the comparison result by the color data comparison unit 35. That is, the color matching determination unit 36 indicates that “even if the difference in color data (for example, CMYK values) of the representative colors among a plurality of pages of the print image data is equal to or less than the first threshold value, It is determined whether or not there is at least one point (region) where the difference in color data (for example, L * a * b * value) corresponding to the representative color between a plurality of pages exceeds the second threshold. If there is no corresponding point (area), color matching of all pages is possible with one color conversion table CP.

  The color conversion table correction unit 37 duplicates (copies) and corrects the color conversion table CP for each corresponding page when the target printed matter of all pages cannot be color-matched by one color conversion table CP, and sets the target for each page. A color conversion table is created according to the color of the scanned image of the printed matter. There are two main methods for correcting the color conversion table. The first is a method of correcting a source profile (target profile) (see FIG. 9 described later) that defines device-independent measurement values (L * a * b * values) from device-dependent CMYK values. The second is a method of correcting a device link profile (DLP) (see FIG. 10 described later) in which the CMYK value of the print image data and the CMYK value of the printer 1 are linked. Details of the correction of the color conversion table will be described later.

  The color conversion table registration unit 38 transmits the color conversion table corrected by the color conversion table correction unit 37 to the controller 2 and stores (registers) the corrected color conversion table in the color conversion table storage unit 24.

[Image processing method]
Next, a procedure example of the image processing method of the image forming system 10 will be described. FIG. 7 is a flowchart illustrating a procedure example of an image processing method of the image forming system 10. In the series of processing shown in this flowchart, for example, a menu screen for instructing execution of color matching between the print image data Im and the target print CS (color sample) as shown in FIGS. 1 and 3 is displayed on the display unit 45. Executed when the user selects “Execute color matching” from the menu screen. Alternatively, when the user makes the inline sensor 61 read the color information of the target print CS, the target print scan image input unit 32 or the print image data input unit 31 displays the menu screen on the display unit 45. You may control to.

  First, when “execution of color matching” is selected, the print image data input unit 31 (see FIG. 6) of the client terminal 3 accepts the input of the print image data Im and uses the print image data Im as the representative color extraction unit. (S1). The print image data input unit 31 may acquire the print image data Im from the controller 2, or may acquire the print image data Im designated by the user operating the operation unit 44 from the nonvolatile storage 42.

  Next, the target printed material scan image input unit 32 receives an input of the scan image of the target printed material CS to be color-matched from the scanner 4 and supplies the scanned image to the representative color extraction unit 33 (S2). As described above, a scan image may be acquired from the scanner 4 or a scan image acquired in advance stored in the nonvolatile storage 42 may be acquired.

  Next, the representative color extraction unit 33 extracts a representative color for color matching from the print image data Im (S3). If the computer 40 is costly and it is allowed to evaluate the colors of all points (all pixels) in the print image data Im, the evaluation is performed on all points without extracting representative colors. It doesn't matter.

  Next, the image alignment unit 34 performs alignment between the print image data and the corresponding scan image, and acquires color data corresponding to the representative color extracted from the print image data Im from the scan image of the target print CS ( S4).

  Next, the color data comparison unit 35 compares the color data of each representative color between pages of the print image data Im, and the difference between the color data of each representative color existing on a plurality of pages is equal to or less than the first threshold value. A representative color that is the same color or substantially the same color is extracted (S5).

  Next, the color data comparison unit 35 calculates the difference between the color data of the plurality of pages of the scan image acquired by the image registration unit 34 corresponding to the representative color extracted as the same color on the plurality of pages of the print image data Im. Then, it is determined whether or not it is larger than the second threshold (S6). Next, when the color data comparison unit 35 determines that there is a color difference larger than the second threshold value between the color data of the scan image of the target print corresponding to the representative colors of the plurality of pages of the print image data (YES in S6), the corresponding color data of the scanned image is added as a color correction candidate to the color conversion table correction list 35a (S7). If the difference is equal to or smaller than the second threshold (NO in S6), the color data comparison unit 35 proceeds to the determination process in step S8.

  Next, after the process in step 7 is completed or in the case of NO determination in step S6, the color data comparison unit 35 selects all the representative colors extracted in the process in step S3 on all the pages having the scanned image of the target printed matter. It is determined whether or not the points have been compared (S8). If the extracted representative color is not compared at all points (NO in S8), the color data comparison unit 35 repeats the processes in steps S5 to S8. Further, when the extracted representative colors are compared at all points (YES in S8), the color data comparison unit 35 proceeds to the process of step S9.

  Next, the color data comparison unit 35 displays the comparison result in step S6 on the display unit 45 (S9). That is, the color data comparison unit 35 corresponds to the representative color even if the difference of the color data (CMYK value) of the representative color between the plurality of pages of the input print image data Im is within the first threshold value range. A point where the colorimetric value (L * a * b * value) of the scanned image of the target printed matter CS exceeds the second threshold is displayed on the display unit 45. Here, the color data comparison unit 35 displays a point that even if one color conversion table CP is corrected, it cannot be adjusted according to the two target prints CS1 and CS2 (see FIG. 3).

  The user may set the color conversion tables CP1 and CP2 for each page of the input print image data Im by looking at the comparison result displayed on the display unit 45, and correct the color conversion tables CP1 and CP2. Further, by correcting the color data of the corresponding representative color of each page of the print image data Im, the representative color (for example, two apple colors Ap) of each page of the print image data Im is changed to the target prints CS1 and CS2. You may correct | amend so that it may correspond to a representative color (for example, apple color Ap1, Ap2). As described above, the user can select either to correct the color conversion table CP for each page or to correct the corresponding page of the print image data Im of the original data.

  The display of the comparison result is not necessarily required, and the process may proceed to the next color conversion table correction process without displaying on the display unit 45. Alternatively, when the user adjusts the color conversion table, it may be completed here without proceeding to the next step.

  Next, the color matching determination unit 36 determines whether the color matching for all pages of the target printed matter CS is possible with one color conversion table CP with respect to the comparison result by the color data comparison unit 35 (S10). . That is, the color matching determination unit 36 indicates that “a plurality of scan images of the corresponding target printed matter are not detected even if the difference in the color data (CMYK value) of the representative color between the plurality of pages of the print image data is equal to or less than the first threshold value. It is determined whether or not there is at least one point (region) where the difference in color data (L * a * b * value) corresponding to the representative color between the pages exceeds the second threshold. If there is no corresponding point (area), color matching of all pages of the target printed matter CS is possible with one color conversion table CP.

  In FIG. 7, it is determined whether or not there is one or more corresponding points (regions). However, the number is not limited to one and may be an arbitrary number of two or more. Alternatively, the color conversion table CP may be corrected when the number of corresponding colors (regions) is equal to or greater than the set threshold value. Alternatively, the display unit 45 may display a screen (GUI) on which an instruction to correct the color conversion table CP can be displayed, and allow the user to determine whether to correct the color conversion table CP.

  Next, when it is possible to perform color matching for all pages of the print image data Im with one color conversion table CP (YES in S10), the color conversion table correction unit 37 ends the processing of this flowchart.

  On the other hand, when it is impossible to perform color matching for all pages of the print image data Im with one color conversion table CP (NO in S10), the color conversion table correcting unit 37 sets one set color conversion table. The color conversion table CP is duplicated for pages that cannot be corrected by the CP (S11). Next, the color conversion table correction unit 37 corrects the duplicated color conversion tables CP1 and CP2 (S12), and transmits the color conversion tables CP1 and CP2 to the controller 2. The color conversion tables CP1 and CP2 transmitted to the controller 2 are stored in the color conversion table storage unit 24.

  When the printer 1 outputs the print image data Im, the color conversion table setting unit 23 of the controller 2 reads the color conversion table CP1 or CP2 from the color conversion table storage unit 24 for each page of the print image data Im. To the color conversion unit 22. Next, the color conversion unit 22 performs color conversion by switching the color conversion tables CP1 and CP2 for each page of the print image data Im, and the print image data Im after color conversion is supplied to the printer 1. Accordingly, the printer 1 can output the printed materials S1 and S2 (see FIG. 3) by matching the colors to the target printed materials CS1 and CS2 for each page of the print image data Im.

  As described above, the correction of the color conversion table CP may be performed by correcting the source profile (target profile) (see FIG. 9 described later) of the device profile (DP) or the device link profile (DLP) ( You may correct (refer FIG. 10 mentioned later). Further, the destination profile of the device profile may be modified.

  In the processing of steps S11 and S12, the color conversion table CP is corrected to perform color matching with respect to the target print CS, but as described above, image color data (CMYK) is applied to the original print image data Im. The color may be adjusted to the target print CS for each page by correcting the value. After the process of step S12, the process of this flowchart is complete | finished.

[Test results of color sample data]
Here, the inspection result of the color sample data will be described. FIG. 8 shows an example of a screen (user interface) showing the inspection result of the color sample data. FIG. 8 shows a case where representative colors of the same color exist between pages of the print image data Im extracted in step S5 (FIG. 7), and the target prints CS1 and CS2 (see FIG. 3) are used as color samples. This is an example.

  In FIG. 8, in the color sample data inspection result screen 50, a preview area 51 and a data area 52 in which the color conversion table correction list 35a is displayed are set. In the preview area 51, a scanned image (a confirmation image) of the target printed matter corresponding to a page in which color matching is impossible with one color conversion table is displayed. In FIG. 8, the scanned images of the target prints CS1 and CS2 corresponding to the pages 1 and 2 of the print image data Im are displayed.

  The color conversion table correction list 35a (an example of a correction list) scans the target printed matter corresponding to the corresponding color data of the plurality of pages of the print image data even if the color data is the same among the plurality of pages of the print image data. In the color data of a plurality of pages of the image, information regarding locations where it is specified that the color data is different among the plurality of pages of the scanned image of the target printed matter is listed. In FIG. 8, for example, information such as an object such as a human face or an apple, color data, or the like is displayed as information regarding a place where the color data is different.

  In addition, the color data comparison unit 35 obtains information regarding the location where the color data is different between a plurality of pages of the scanned image of the target printed matter, information about the corresponding color data of the print image data (CMYK value), Displayed together with information (L * a * b * value) about the corresponding color data of the scanned image of the target printed matter, or both. Thereby, the user can confirm the information regarding the location of the corresponding color data and the information regarding the color data.

  In FIG. 8, the color conversion table correction list 35a has fields of record number (#), comparison source, comparison destination, ΔE, determination, and correction. The comparison source field indicates information about a page (scanned image) as a reference for comparison, and in this example, the scanned image of the target printed matter CS1 corresponds to the comparison source field. The comparison destination field indicates information about pages to be compared (scanned images), and in this example, the scanned image of the target print CS2 corresponds to the comparison destination field.

  Both the comparison source data and the comparison destination data have pages, images, and data items. The page field indicates a scanned image page (page 1 in FIG. 8) of a target printed matter having different color reproduction despite the same color among a plurality of pages of print image data. The image field indicates a thumbnail of the scanned image of the target printed matter with different color reproduction despite the same color among a plurality of pages of the print image data (in FIG. 8, a reduced image of the apple of color Ap1). The data field includes a color system value (CMYK value) of the device-dependent color space of the representative color extracted from the corresponding print image data and a color system value (L *) of the device-independent color space of the corresponding scan image. a * b * value) and the area occupied by the representative color.

  The ΔE field indicates the color difference between the representative color of the comparison source scan image (target print CS1) and the corresponding representative color of the comparison target scan image (target print CS2). The determination field indicates a result of the color matching determination unit 36 determining whether or not a single color conversion table can match a plurality of target printed materials from the color difference indicated in the ΔE field. This determination corresponds to the determination process in step S6. As the determination result, “OK” is displayed when correction is possible with one color conversion table, and “NG” is displayed when correction is not possible with one color conversion table.

  In FIG. 8, the color data comparison unit 35 indicates information regarding the location where the color data is specified to be different between a plurality of pages of the scanned image of the target printed matter, and the corresponding color data between the plurality of pages of the scanned image of the target printed matter. Is displayed together with the color difference ΔE. The user can use the color difference ΔE as a material for determining whether correction of the color conversion table or print image data is necessary or if correction is necessary.

  The correction field indicates which color data of the color data (record number) listed in the color conversion table correction list 35a is to be corrected. A check box 54 is provided in the correction field, and when the color difference in the ΔE field is large, the check is automatically entered. Note that the user may check the check box 54 so that the color data to be corrected can be arbitrarily selected. Thus, for example, for important color data of the target printed matter, even if the color difference ΔE is small, the check box 54 is checked and the color conversion table is corrected, so that it is possible to output an image that matches the color of the target printed matter. .

  Note that the color data comparison unit 35 may display information on the print image data and the corresponding color data of the scan image of the target print in the color conversion table correction list 35a in a predetermined priority order. For example, the priority order is an area order, a color difference order, or an order individually set by the user via the operation unit 44. In FIG. 8, the color conversion table correction list 35a is displayed in descending order of the area of the color data. Since the display priority order can be arbitrarily selected or designated, the user can display the color data information in the color conversion table correction list 35a in a desired priority order, thereby improving convenience.

  In FIG. 8, two points (records # 1 and # 2) of the human face color and apple color are extracted on the assumption that the same CMYK values are used for page 1 and page 2 of the print image data. Then, the CMYK value of the representative color of the print image data, the colorimetric value (L * a * b * value) of the scanned image corresponding thereto, the respective areas, and the color difference (ΔE) between them are displayed. Here, the color difference of the colorimetric values (color Ap1, color Ap2) of the apple image of record # 2 is “NG”. When the user sees the result and operates the color conversion table correction button 53 by the operation unit 44, the color conversion table correction unit 37 instructs the color conversion table CP to be corrected for the color data of the record # 2.

  As described above, according to the present exemplary embodiment, the color conversion table can be corrected only for pages that require print image data. Therefore, even when there are a plurality of target prints having different color reproduction due to variations in the printing press, etc., despite the same color among a plurality of pages of the print image data, the colors of the output image based on the print image data are It is possible to match the color of the target printed matter (color Ap1, color Ap2 in FIG. 8) (second effect shown in FIG. 3). Further, since the color conversion table is duplicated only for necessary pages, it is not necessary to create a new color conversion table for every page, and the processing load on the client terminal 3 can be minimized.

  When there are a plurality of color conversion tables that can be correction candidates, a screen for specifying the color conversion table may be displayed after the correction button 53 of the color conversion table is operated, and the user may be allowed to specify it. This improves the accuracy of color conversion and improves usability.

  In FIG. 8, the color data comparison unit 35 calls “!” Together with a frame to call attention to each apple image in the scanned images of the target print CS1 (page 1) and the target print CS2 (page 2). A symbol M1 is displayed. As a result, the user can recognize that color matching for all pages of the print image data Im is impossible with one color conversion table CP. Thereby, the user can consider and select one of (1) switching the color conversion table for each page of the print image data or (2) correcting the print image data by the user. Therefore, it is possible to match the color of the printed material output based on the print image data with respect to both target printed materials (first effect shown in FIG. 2). Further, by displaying the above contents on the display device, the user can check the color reproduction state before outputting to the recording material, so that useless output can be reduced.

  In FIGS. 2 and 8, the mark M, the mark M1, and the frame are displayed on the scanned image of the target printed matter. However, these may be displayed on the image of the print image data.

  In step S6 of FIG. 7 described above, it has been described that the color data of the portion where the color difference between the pages of the scanned image exceeds the second threshold is added to the color conversion table correction list 35a. Not exclusively. For example, as in record # 1 shown in FIG. 8, color data ("determination OK") in which the color difference of the color data is smaller than the second threshold value among a plurality of pages of the scanned image is registered in the color conversion table correction list 35a. May be. Thereby, the user can grasp that there is a certain color difference in the color data between a plurality of pages of the scanned image, although it is not necessary to immediately correct the color conversion table.

  In the example of FIG. 8, the scan images of two target prints that cannot be corrected by one color conversion table are displayed side by side, but three or more corresponding pages may be displayed.

[Configuration of color conversion table]
Here, the color conversion table will be described with reference to FIGS.
The color conversion table is also called a profile. Among the profiles, the ICC profile is widely used not only in the printing industry but also in the IT (Information Technology) industry, and is a de facto standard. Hereinafter, an ICC profile will be described as an example. Color management by ICC profile is roughly classified into the following two.
(1) Method using device profile (hereinafter referred to as “DP”) (2) Method using device link profile (hereinafter referred to as “DLP”)

(Device profile (DP))
The device value (CMYK value, RGB value, etc.) is a value dependent on the model, and DP is a device value associated with a model-independent value (XYZ value, L * a * b * value, etc.). The DP is composed of an LUT from a device value to a model-independent value and an LUT from a model-independent value to a device value. For example, in the case of a DP of a CMYK printer, an LUT (A2B table: example of a first color conversion table) that converts CMYK (first color space) into L * a * b * (second color space); It is composed of an LUT (B2A table: example of second color conversion table) for converting L * a * b * (second color space) into CMYK (third color space). Since this model-independent value is a color space that connects profiles, it is called a profile connection space (PCS).

  In DP, a rendering intent can be selected depending on the color reproduction policy. The types of rendering intents include perception, colorimetry, and saturation, for example, and an LUT is prepared for each. In this case, the DP has three types of LUTs. At the time of color conversion, one rendering intent is selected, and the LUT associated with that rendering intent is used.

  In order to perform color conversion, a DP of a target device is required, which is called a source profile (sometimes called a target profile). For example, a standard profile such as an offset printing machine profile or Japan Color is selected as the source profile. The DP of the device to be output is called a destination profile (sometimes called a printer profile). In this case, a profile of a printer (for example, printer 1) that actually outputs a printed matter is selected. The input CMYK value becomes a model-independent value through the A2B table of the source profile, and is converted into another CMYK value through the B2A table of the destination profile.

  FIG. 9 shows the flow of color conversion processing using a device profile. Through such two-step conversion, the CMYK values (C, M, Y, K) ′ corresponding to the CMYK values (C, M, Y, K) of the target device (source) are transferred to the printer ( Can be output at the destination).

(For device link profile (DLP))
The DLP is a collection of information for converting color values using the DP, that is, device value → model independent value → device value, into one LUT. That is, the DLP is an LUT that associates an input device value with an output device value. The DLP is created by integrating a device profile (source profile) of an input device and a device profile (destination profile) of an output device (printer or the like). When DLP is used for color conversion, the process at the time of color conversion in color management is only once. For example, when converting from CMYK (first color space) of one device to CMYK (third color space) of another device, the color space does not depend on the device (such as three-dimensional L * a * b *). Since it is not necessary to convert the information, the loss of information (if you want to keep black information, etc.) is reduced.

  FIG. 10 shows the flow of color conversion processing using a device link profile. In the case of DLP, there is no concept of rendering intent and it has only one LUT. Therefore, by applying the device link profile LUT to the input CMYK values (C, M, Y, K), the target CMYK values (C, M, Y, K) ′ can be directly output.

[Example of color conversion table correction]
FIG. 11 is an explanatory diagram showing an example of correcting the A2B table of the source profile in the device profile. FIG. 11A shows the A2B table before correction, and FIG. 11B shows the A2B table after correction. Here, an example of correcting the apple color in FIG. 8 by correcting the A2B table of the source profile will be described.

  The A2B table of the source profile SP before correction shown in FIG. 11A is an example of the color conversion table CP that originally existed. The A2B table of the corrected source profile SP ′ in FIG. 11B is an example in which the apple color Ap1 (yellow apple) of the first page is corrected so as to be reproduced. In order to convert the input point of CMYK to a desired position (L * a * b * value) in the L * a * b * space on the output side, the area around the target position in the L * a * b * color space Need to be corrected across the grid. In general, the L * a * b * values of the four grids around the target position are corrected. This adjustment range (number of target grids) may be specified by the user.

<2. Modification>
The present invention is not limited to the above-described embodiment, and various other application examples and modifications can of course be taken without departing from the gist of the present invention described in the claims.

  In the above-described embodiment, an example in which the L * a * b * color system is used as the color system (color coordinate system) of the device-independent color space representing the target value of the color has been described. It is not limited to this. For example, the XYZ color system (stimulus value Y including luminance (brightness), color stimulus value X, Z), Yxy color system (luminance Y, chromaticity coordinates x, y) defined by the International Lighting Commission described above , L * u * v * color system, HSV color system (hue H (hue), saturation S (saturation), lightness V (value) or B (brightness))), HLS color system (hue H (Hue), saturation S (saturation), luminance L (luminance)), and YCbCr color system (luminance Y, color difference Cb, Cr) can be used.

  Further, for example, the above-described embodiment is a detailed and specific description of the configuration of the apparatus and the system in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the described components. . Moreover, it is also possible to add, delete, and replace other components for a part of the configuration of the embodiment.

  In addition, each of the above-described components, functions, processing units, and the like may be realized by hardware by, for example, designing an integrated circuit or the like. Further, the control lines and information lines are those that are considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. In practice, it may be considered that almost all components are connected to each other.

  DESCRIPTION OF SYMBOLS 1 ... Printer, 2 ... Controller, 3 ... Client terminal (image processing apparatus), 4 ... Scanner, 10 ... Image forming system, 23 ... Color conversion table setting part, 24 ... Color conversion table memory | storage part, 31 ... Print image data input 32: Target printed product scan image input unit, 33 ... Representative color extraction unit, 34 ... Image alignment unit, 35 ... Color data comparison unit, 35a ... Color conversion table correction list, 36 ... Color matching determination unit, 37 ... Color Conversion table correction unit 38 ... Color conversion table registration unit 41 ... Control unit 45 ... Display unit 50 ... Color sample data inspection result screen 51 ... Preview region 52 ... Data region 53 ... Correction of color conversion table Button, CS, CS1, CS2 ... target printed matter, CP, CP1, CP2 ... color conversion table, S1, S2 ... mark Thing

Claims (13)

A print image data input unit that accepts input of print image data composed of a plurality of pages;
A scan image input unit that receives an input of a scan image of a target printed matter in which a target color to be reproduced of the print image data is output;
A color data association unit that associates the color data of the print image data with the color data of the scan image of the target printed matter;
A comparison process is performed using the color data of the print image data and the color data of the scanned image of the target printed matter, and even if the color data is the same among a plurality of pages of the print image data, a plurality of the print image data A color data comparison unit that identifies locations where the color data differs among the plurality of pages of the scanned image in the color data of the plurality of pages of the scanned image of the target printed matter corresponding to the corresponding color data of the page of the image. Processing equipment. The image according to claim 1, further comprising: a display unit configured to display information about the corresponding color data at a location where the color data is different among a plurality of pages of the scanned image of the target printed matter specified by the color data comparison unit. Processing equipment. A color conversion table used for color conversion of the print image data;
In the color data of the plurality of pages of the scanned image of the target printed matter corresponding to the corresponding color data of the plurality of pages of the print image data, even if the color data is the same among the plurality of pages of the print image data, When color data is different between a plurality of pages of a scanned image, the color conversion table is copied for each corresponding page, and the copied color conversion is performed in accordance with the color data of the scanned image for each page of the target printed matter. The image processing apparatus according to claim 1, further comprising a color conversion table correction unit that corrects the table. In the color data of the plurality of pages of the scanned image of the target printed matter corresponding to the corresponding color data of the plurality of pages of the print image data, even if the color data is the same among the plurality of pages of the print image data, When the color data is different among a plurality of pages of the scanned image, the print image data is corrected according to a user instruction so that the color of the output image based on the print image data of the corresponding page matches the color of the target printed matter The image processing apparatus according to claim 1, further comprising: an image correcting unit that performs the processing. An operation unit that generates an operation signal according to a user input operation;
The color data comparison unit includes a first threshold for determining whether or not a difference in color data between a plurality of pages of the print image data is within a predetermined range, and a scan image of the target print product. And setting at least one second threshold value for determining whether or not the difference in color data between a plurality of pages is within a predetermined range based on the operation signal generated by the operation unit. Item 5. The image processing apparatus according to any one of Items 1 to 4. The first threshold value and the second threshold value are generated by the operation unit for each color data of the scanned image of the print image data or the target printed matter, for each area formed by the color data, or for both. The image processing apparatus according to any one of claims 1 to 5, wherein the image processing apparatus is set based on the operation signal that has been set. The color data comparison unit may include a plurality of scan images of the target printed matter corresponding to corresponding color data of a plurality of pages of the print image data even if the color data is the same among the plurality of pages of the print image data. 7. The correction list in which information relating to locations where the color data is specified to be different among a plurality of pages of the scanned image is displayed on the display unit in the color data of the page. 7. The image processing apparatus according to item. The image processing apparatus according to claim 7, wherein information about the print image data and corresponding color data of the scanned image of the target printed matter in the correction list is displayed in a predetermined priority order. The image processing apparatus according to claim 8, wherein the priority order is an area order, a color difference order, or an order individually set by the user via the operation unit. The color data comparison unit may include a plurality of scan images of the target printed matter corresponding to corresponding color data of a plurality of pages of the print image data even if the color data is the same among the plurality of pages of the print image data. In the color data of a page, a mark indicating a location where color data is specified to be different among a plurality of pages of the scanned image is displayed on the image of the printed image data or the scanned image of the target printed matter. Item 10. The image processing apparatus according to any one of Items 1 to 9. The color data comparison unit may include a plurality of scan images of the target printed matter corresponding to corresponding color data of a plurality of pages of the print image data even if the color data is the same among the plurality of pages of the print image data. In the page color data, information on the location where the color data is specified to be different among a plurality of pages of the scan image, information on the color data of the print image data, and the color of the scan image of the target printed matter The image processing apparatus according to claim 1, wherein the image processing apparatus displays the information together with information about the data or both. The color data comparison unit may include a plurality of scan images of the target printed matter corresponding to corresponding color data of a plurality of pages of the print image data even if the color data is the same among the plurality of pages of the print image data. Information regarding a location where color data is specified to be different among a plurality of pages of the scanned image in the color data of the page is displayed together with a color difference of the corresponding color data between the plurality of pages of the scanned image of the target printed matter. Item 12. The image processing device according to any one of Items 1 to 11. Accepting input of print image data composed of multiple pages;
Receiving an input of a scanned image of a target printed matter in which a target color to be reproduced of the print image data is output;
Associating the color data of the print image data with the color data of the scanned image of the target printed matter;
A comparison process is performed using the color data of the print image data and the color data of the scanned image of the target printed matter, and even if the color data is the same among a plurality of pages of the print image data, a plurality of the print image data An image processing method comprising: identifying, in the color data of a plurality of pages of the scanned image of the target printed matter corresponding to the corresponding color data of the page, a location where the color data differs among the plurality of pages of the scanned image.

Images