JP6503747B2 - Color correction chart creation control program, image forming apparatus, and color correction chart creation method - Google Patents

Description

  The present invention relates to a color correction chart preparation control program for controlling preparation of a sheet (hereinafter referred to as a color correction chart) used for color correction of the image forming apparatus, an image forming apparatus for printing the color correction chart, and the related The present invention relates to a method of creating a color correction chart in a system including an image forming apparatus.

  When color printing is performed using an image forming apparatus such as a copier or multifunction peripheral (MFP: Multi Function Peripheral) having a color printing function, color management for accurately reproducing the colors included in each page of the job is performed. is important. Therefore, conventionally, a color correction chart in which color patches are arranged is measured by an inline sensor provided in a scanner or an image forming apparatus, and color information of the color patches is compared with color information read by the scanner or inline sensor. The color correction is performed in which feedback is performed so that the amount of change in color falls within an appropriate range.

  In order to perform color correction by measuring the color patches of the color correction chart, it is necessary to detect only the reflected light from the color patch to be measured. However, in reality, diffuse reflection light of adjacent color patches is reflected by the structure and enters, or diffuse reflection light of the sheet around the color patch to be measured enters, so that highly accurate measurement can be performed. However, there is a problem that the accuracy of color correction is lowered. As a method of reducing the influence of the irregularly reflected light, a mechanism for blocking irregularly reflected light from around the color patch to be measured may be provided, but with this method, cost increases due to the addition of the mechanism and the increase in the number of parts. In particular, when measuring with an in-line sensor provided inside the image forming apparatus, it is difficult to provide a special mechanism for the in-line sensor, and the cost increase due to the addition of the mechanism and the increase in the number of parts becomes a major problem.

  With regard to a technique for suppressing such irregular reflection from the color patch periphery, for example, Patent Document 1 below is a test chart in which a plurality of color areas are arranged in a predetermined direction, and classified based on the configuration of color components. The second image area in which the first image area in which the color areas consisting of the colors belonging to the first color group are arranged and the color area consisting of the colors belonging to the second color group are arranged A test chart is disclosed in which a first image area and a black image area disposed between the second image area are displayed.

JP 2007-170883 A

  However, according to Patent Document 1, black is generated between image areas in which color areas composed of colors belonging to each color group are arranged (that is, between an aggregation of a plurality of color areas and an aggregation of adjacent color areas). The image areas of the above are provided, and since there is no black image area between each color area, it is not possible to reliably prevent diffuse reflection light from the surroundings. Further, Patent Document 1 provides a black image area between areas arranged in the sub-scanning direction, and since there is no black image area between the areas in the main scanning direction, it is possible to use isolated color patches. On the other hand, irregularly reflected light can not be reliably prevented.

  The present invention has been made in view of the above problems, and the main object thereof is to effectively suppress the influence of irregular reflection around the color patch even for an isolated color patch, and to accurately carry out the color patch. It is an object of the present invention to provide a color correction chart creation control program capable of measuring colors, an image forming apparatus, and a color correction chart creation method.

One aspect of the present invention is a color correction chart creation control program operated by a control device that instructs an image forming apparatus including a printing unit and a color measurement unit to print, and the color measurement unit of the image forming apparatus is predetermined When color information of the color patch adjacent to the predetermined color patch is used as the distance information when the color patch substantially eliminates the influence of diffuse reflection of the color measurement light , when instructing printing of color correction chart for performing color correction, on the basis of the distance information previously stored in the storage unit, it is formed around the color patches each be arranged in the color correction chart A first process of specifying the width of the black frame; a second process of generating a black frame-attached color patch image in which the black frame of the specified width is formed around each of the color patches; A third process of generating a print image of the color correction chart in which a black patched color patch image is arranged, data of the print image is transmitted to the image forming apparatus, printing of the color correction chart and each color A fourth process for instructing patch color measurement is performed.

One aspect of the present invention is an image forming apparatus including a printing unit, a color measurement unit, and a storage unit, wherein the color measurement unit of the image forming apparatus measures the predetermined color patch when the color measurement is performed. When a distance for substantially eliminating the influence of diffuse reflection of colorimetric light in color patches adjacent to color patches is used as distance information, the color correction chart for performing color correction is stored in advance in the storage unit. based on the distance information, to identify the width of the black frame formed around each of the color patches to be arranged in the color correction chart, around the color patches of the respective, forming a black frame of the specified width An image data processing unit that generates a color patch image with a black frame, a RIP unit that generates a print image of the color correction chart on which the color patch image with a black frame is arrayed; Chart is printed, characterized in that and a job processing control unit for colorimetry each color patch of the color measurement section.

One aspect of the present invention is a method for creating a color correction chart in a printing system in which an image forming apparatus including a printing unit and a color measurement unit, and a control device instructing the image forming apparatus to print by a communication network. When the color measurement unit of the image forming apparatus measures a predetermined color patch, the distance information is a distance substantially eliminating the influence of diffuse reflection of color measurement light in the color patch adjacent to the predetermined color patch. If a, the control device, wherein the color correction of the image forming apparatus when instructing printing of color correction chart for performing, based on pre-stored the distance information in the storage unit, the color correction Processing for specifying the width of the black frame formed around each color patch arranged in the chart, and the black frame formed with the black frame of the specified width around each color patch A second process of generating a color patch image, a third process of generating a print image of the color correction chart on which the black framed color patch image is arranged by the RIP unit, and the image formation of the print image data And the image forming apparatus prints the color correction chart by the printing unit based on data of the print image, and the color measurement unit It is characterized in that color patches are measured.

  According to the color correction chart preparation control program, the image forming apparatus and the color correction chart preparation method of the present invention, the influence of irregular reflection around the color patch is effectively suppressed even for an isolated color patch Color patches can be measured.

  The reason is that the color correction chart preparation control program arranges a black frame around each color patch and prints the color correction chart. Also, depending on the color of the color patch adjacent in the sub-scanning direction and / or the main scanning direction, the width of the black frame may be changed, or when a black frame of a predetermined width can not be arranged between color patches To expand the

It is a schematic diagram which shows the structure of the printing system which concerns on the 1st Example of this invention. It is a schematic diagram which shows the other structure of the printing system which concerns on the 1st Example of this invention. It is a block diagram showing composition of a client device concerning a 1st example of the present invention. FIG. 1 is a block diagram showing the configuration of a printer controller according to a first embodiment of the present invention. FIG. 1 is a block diagram showing a configuration of an image forming apparatus according to a first embodiment of the present invention. FIG. 1 is a schematic view showing a configuration of an engine of an image forming apparatus according to a first embodiment of the present invention. FIG. 6 is a flowchart showing the operation of the image forming apparatus according to the first embodiment of the present invention. It is a figure which shows an example of the chart for color correction which concerns on the 1st Example of this invention. FIG. 7 is a flowchart showing the operation of the image forming apparatus according to the second embodiment of the present invention. FIG. 14 is a flowchart showing an operation (an example of a black-framed image patch creation process) of the image forming apparatus according to the second embodiment of the present invention. FIG. 14 is a flowchart showing an operation of the image forming apparatus according to the second embodiment of the present invention (another example of the black-framed image patch creation process). It is a figure explaining the influence by the scattered light in the in-line sensor of the image forming apparatus which concerns on the 2nd Example of this invention. It is a table referred when determining the width of the black frame concerning a 2nd example of the present invention. It is a figure which shows an example of the chart for color correction which concerns on the 2nd Example of this invention. It is a figure which shows the other example of the chart for color correction which concerns on the 2nd Example of this invention. FIG. 14 is a flowchart showing an operation (an example of a black-framed image patch creation process) of the image forming apparatus according to the third embodiment of the present invention.

  As described in the background art, in order to perform color correction by measuring the color patches of the color correction chart, it is necessary to detect only the reflected light from the color patch to be measured, but in practice Since the diffuse light from the periphery of the color patch to be colored (light from the diffuse reflection from the adjacent color patch reflected by the structure or light from the paper around the color patch to be measured) is also detected. Can not be measured high, and the accuracy of color correction is degraded. As a method of reducing the influence of the irregular reflection, in Patent Document 1, in order to suppress the influence of the in-plane unevenness in the sub-scanning direction, sub-scanning of color group 1 classified based on the color components of the patch and another color group 2 A black patch of a certain size is placed at the boundary of the direction.

  However, Patent Document 1 provides a black image area between image areas (a collection of a plurality of color areas) in which color areas consisting of colors belonging to a color group are arranged, and between individual color areas Since there is no black image area and there is no black image area in the main scanning direction, irregular reflected light from the surroundings can not be reliably prevented.

  Therefore, in one embodiment of the present invention, an image of a black framed color patch is generated by surrounding each color patch with a black frame, and a color measurement chart image in which a plurality of black framed color patch images are arranged is generated. Do. In addition, the size of the black frame surrounding the color patch subject to color measurement based on the influence of diffuse reflection that the color patch subject to color measurement receives from the surrounding color patch or paper (hereinafter, simply referred to as the effect of ambient diffuse reflection). Determine the (width). In addition, when the black frame of the determined size can not be arranged around the color patch to be measured, the interval of the color patch is expanded so that the black frame can be arranged.

  As a result, the influence of ambient diffuse reflection can be effectively suppressed, color patches can be measured accurately, and highly accurate color correction becomes possible.

  In order to describe the above-described embodiment of the present invention in further detail, a color correction chart creation control program, an image forming apparatus, and a color correction chart creation method according to a first embodiment of the present invention will be described with reference to FIGS. This will be described with reference to FIG. 1 and 2 are schematic diagrams showing the configuration of the printing system of this embodiment, FIG. 3 is a block diagram showing the configuration of the client apparatus, and FIG. 4 is a block diagram showing the configuration of the printer controller. 5 is a block diagram showing the configuration of the image forming apparatus, and FIG. 6 is a schematic view showing the configuration of the engine of the image forming apparatus. 7 is a flowchart showing the operation of the printer controller, and FIG. 8 is a diagram showing an example of a color correction chart.

  As shown in FIG. 1, in the printing system of this embodiment, a client device 10 connectable by a communication network, a printer controller 20, and an image forming device 30 are arranged on an intranet. Although Ethernet (registered trademark) or the like can be used as the standard of the communication network, data transfer from the printer controller 20 to the image forming apparatus 30 can also use IEEE 1394, Parallel or the like besides Ethernet (registered trademark). It is. Although the printer controller 20 is provided separately from the image forming apparatus 30 in FIG. 1, the printer controller 20 may be included in the image forming apparatus 30 as shown in FIG. 2. Hereinafter, each apparatus will be described in detail based on the configuration of FIG.

[Client device]
The client device 10 is a computer device such as a personal computer, and includes a control unit 11, a storage unit 12, a network I / F unit 13, a display unit 14, an operation unit 15 and the like as shown in FIG. Ru.

  The control unit 11 includes a central processing unit (CPU) 11 a and a memory such as a read only memory (ROM) 11 b and a random access memory (RAM) 11 c, which are connected via a bus. The CPU 11a reads the program from the ROM 11b or the storage unit 12, develops the program in the RAM 11c, and executes the program to perform overall control of the client device 10.

  The control unit 11 is, as shown in FIG. 3B, an OS (Operating System) 16 such as Windows (registered trademark) or Macintosh (registered trademark), and a document creation application 17 for creating a document on the OS 16. The document data created by the document creation application 17 is converted into a language (PCL (Page Control Language) such as PCL (Printer Control Language) or PS (Post Script)) interpretable by the printer controller 20, and printing conditions and It also functions as a printer driver 18 or the like that generates a print job by designating processing conditions.

  The storage unit 12 is configured by an HDD (Hard Disk Drive), an SSD (Solid State Drive), or the like, and stores a program for the CPU 11a to control each unit, data of a document, a print job, and the like.

  The network I / F unit 13 includes a NIC (Network Interface Card), a modem, and the like, establishes a connection with the printer controller 20 connected via a network, and transmits a print job and the like.

  The display unit 14 is configured by an LCD (Liquid Crystal Display) or the like, and a screen for creating a document, document printing conditions (number of copies, paper type, single / double-sided, color / monochrome etc.) and post-processing conditions (tab sheet insertion) Display a screen to set up, staple, punch, etc.). The operation unit 15 is composed of a keyboard, a mouse, a touch panel integrated with the display unit 14 and the like, and enables operations such as creation of a document and setting of printing conditions and post-processing conditions.

[Printer controller]
The printer controller 20 is a control device such as a computer device, and as shown in FIG. 4A, includes a control unit 21, a storage unit 22, a network I / F unit 23, a printer I / F unit 24, and the like.

  The control unit 21 includes a CPU 21a and memories such as a ROM 21b and a RAM 21c, which are connected via a bus. The CPU 21a reads the program from the ROM 21b or the storage unit 22, develops the program in the RAM 21c, and executes the program, thereby controlling the entire printer controller 20.

  The control unit 21 also functions as a job processing control unit 25, an image data processing unit 26, a RIP (Raster Image Processor) unit 27 and the like as shown in FIG. 4B.

  The job processing control unit 25 analyzes the PDL command of the print job received from the client device 10, and uses the number of copies, paper type, both sides / one side, color / monochrome, objects used for each page (Image / Graphic / Text Get job settings such as tab sheet insertion, post processing such as stapling and punching. Then, the control unit 27 causes the RIP unit 27 to generate bitmap image data, and causes the image forming apparatus 30 to execute print processing based on the generated bitmap image data.

  In addition, when the job processing control unit 25 receives a color correction request from the image forming apparatus 30, the job processing control unit 25 instructs creation of a color correction chart including information of paper type to be subjected to color correction, color information of color patches, layout information and the like. Information is created and transferred to the image data processing unit 26, and the image data of the color correction chart created by the RIP unit 27 is transmitted to the image forming apparatus 30, and creation of a color correction chart and color measurement are instructed. Then, based on the colorimetric data acquired from the image forming apparatus 30, color correction such as updating a color conversion table is performed such that the measured color falls within a predetermined color gamut.

  The image data processing unit 26 generates an image of a color patch necessary for color correction in accordance with the creation instruction information of the color correction chart transferred from the job processing control unit 25. At this time, in the present embodiment, in order to suppress the influence of diffuse reflection light from the periphery of each color patch, the paper type and the distance, which is substantially eliminated by the influence of diffuse reflection of the surroundings, stored in the storage unit 22 in advance. An image in which a black frame width corresponding to a distance corresponding to a paper type to be subjected to color correction is specified with reference to a correspondence table, and an image in which a black frame is arranged around each color patch (referred to as a color patch image with black frame). And the color patch image with black frame and the layout information of the color patch are transferred to the RIP unit 27 to instruct generation of a print image of the color correction chart. In addition, when the number of page images exceeds the limited number of pages designated in advance for the color correction chart, the image data processing unit 26 operates the panel for confirming whether to execute color correction on the panel of the image forming apparatus 30. The unit 34 (in the case where the printer controller 20 is provided with a display unit, the display unit) is displayed. Note that, for example, the distance from which the light emitted from the light source for color measurement is adjacent to the color patch of the color measurement target and the circumference of the color patch of the color measurement target are the distances at which the influence of diffuse reflection in the surroundings is substantially eliminated. The amount of light irregularly reflected by the sheet of paper and incident on the in-line sensor 36 is determined by measurement or simulation, and the amount of light is a distance that is equal to or less than a threshold determined based on the accuracy of color correction.

  The RIP unit 27 translates PDL data to generate intermediate data, performs color conversion on the intermediate data using a color conversion table, performs rendering, and generates a print image of each page of the document (referred to as a page image). ) (This series of processing is called RIP processing). Further, the RIP unit 27 is a color correction chart in which each black framed color patch image is arranged on the page according to the layout information according to the black framed color patch image and the color patch layout information transferred from the image data processing unit 26. Generate a page image. In addition, the RIP unit 27 performs screen processing, tone correction, density balance adjustment, thinning, halftone processing, and the like on the page image as necessary. Then, the RIP unit 27 outputs the data of the generated page image to the image forming apparatus 30, and causes the image forming apparatus 30 to execute the printing process.

  The job processing control unit 25, the image data processing unit 26, and the RIP unit 27 (in particular, the job processing control unit 25 and the image data processing unit 26) may be configured as hardware, or the control unit 21 may be a job. It is configured as a color correction chart creation control program to function as the processing control unit 25, the image data processing unit 26, and the RIP unit 27 (in particular, the job processing control unit 25 and the image data processing unit 26). The program may be executed by the CPU 21a.

  The storage unit 22 includes an HDD, an SSD, and the like, and programs (including the above-described color correction chart creation control program) for the CPU 21a to control the respective units, print jobs, page image data, color conversion tables, and paper types And a table that associates the black frame with the width of the black frame.

  The network I / F unit 23 includes a NIC, a modem, and the like, establishes a connection with the client device 10 connected via the network, and receives a print job and the like. The printer I / F unit 24 is a dedicated interface for connecting to the image forming apparatus 30, and transmits page image data and instruction information (print instruction information and color measurement instruction information) to the image forming apparatus 30, or an image The color correction request is received from the forming device 30.

[Image forming apparatus]
The image forming apparatus 30 is a multifunction peripheral that executes printing in accordance with an instruction from the printer controller 20, and as shown in FIG. 5, the control unit 31, the controller I / F unit 32, the scan unit 33, the panel operation unit 34, and printing. A printing unit 35 and an in-line sensor (color measurement unit) 36 are provided.

  The control unit 31 includes a CPU 31a and memories such as a ROM 31b and a RAM 31c, which are connected via a bus. The CPU 31a reads the program from the ROM 31b, develops the program in the RAM 31c, and executes the program to perform overall control of the image forming apparatus 30. Further, the control unit 31 counts the number of sheets for color printing, the usage time of the apparatus, and the like, and determines that color correction is necessary when the count value reaches a predetermined value. Send a correction request.

  The controller I / F unit 32 is a dedicated interface for connecting to the printer controller 20, and receives page image data and instruction information (print instruction information and color measurement instruction information) from the printer controller 20. Send a color correction request to

  The scanning unit 33 is a portion that optically reads image data from a document placed on a document table, and a light source that scans the document and a CCD (Charge Coupled Devices) that converts light reflected from the document into an electrical signal. Etc., and an A / D converter for A / D converting an electric signal.

  The panel operation unit 34 is a touch panel in which a touch sensor consisting of transparent electrodes in a grid shape is formed on a display unit such as an LCD, and displays various screens including a color correction suspension setting screen described later. Enables various operations.

  The print unit (print unit) 35 executes print processing based on the page image. Specifically, as shown in FIG. 6, an exposure unit that irradiates and exposes a laser beam based on a page image, a photosensitive drum, a developing device, a charging device, a photosensitive member cleaning unit, and a primary transfer roller. And an intermediate belt functioning as an intermediate transfer member which is rotated by a roller and conveys the toner image formed by the image forming portion onto a sheet, and is formed on the intermediate belt. A secondary transfer roller that transfers the transferred toner image to a sheet, a fixing unit that fixes the toner image transferred to the sheet, a sheet feed roller or resist roller that transports the sheet, a loop roller, a reverse roller, a sheet discharge roller, etc. And the like.

  The in-line sensor (color measurement unit) 36 is formed of, for example, three types of sensors of RGB provided on the sheet conveyance path between the fixing unit and the discharge tray, and the color formed by the print unit 35 on the sheet Each color chart of the correction chart is measured and output as colorimetric data.

  1 to 6 show an example of the printing system according to the present embodiment, and the configuration and control of each device can be appropriately changed as long as a page image of a color correction chart on which a black framed color patch image is arranged can be created. It is possible.

  For example, in the above description, the color correction chart is measured by the inline sensor 36. However, the color measurement chart may be measured by the scan unit 33. In the above description, the control unit 21 of the printer controller 20 has the functions of the image data processing unit 26 and the RIP unit 27. However, when the printer controller 20 is included in the image forming apparatus 30, The control unit 31 of the image forming apparatus 30 may be configured to have the functions of the image data processing unit 26 and the RIP unit 27 (or cause the CPU 31a to execute a color correction chart creation control program).

  Next, the general printing operation in the printing system of the above configuration will be outlined.

  First, a document for printing is created by a document creation application 17 (for example, Word (registered trademark), Excel (registered trademark) of Microsoft (registered trademark), etc.) installed in advance in the client device 10. The data in the application file format created by the document creation application 17 is converted into PDL data in the PDL file format by the printer driver 18 and transmitted to the printer controller 20 via the intranet. At this time, an instruction for performing post-processing specific to the image forming apparatus 30 is set in the PDL data by the setting of the printer driver 18.

  The printer controller 20 receives PDL data, the PDL data is arranged in the printer controller 20 in the order of arrival, the job processing control unit 25 analyzes the setting of the job, and the RIP unit 27 converts it into a page image. Then, the instruction information based on the job setting is transmitted to the image forming apparatus 30 together with the data of the page image, and the image forming apparatus 30 executes the printing process according to the data of the page image and the instruction information.

  Next, an example of the operation of the printer controller 20 when a color correction request is received from the image forming apparatus 30 during processing of the print job will be described. The CPU 21a executes the processing of each step shown in the flowchart of FIG. 7 by developing the color correction chart creation control program stored in the ROM 21b or the storage unit 22 on the RAM 21c and executing the program. The control unit 31 of the image forming apparatus 30 automatically determines the necessity of color correction by counting the number of sheets for color printing, the use time of the apparatus, and the like, and determines that the color correction is necessary. In this case, it is assumed that a color correction request is sent to the printer controller 20. Further, since the degree of diffuse reflection varies depending on the paper type to be subjected to color correction, a table correlating the paper type to be subjected to color correction with the width of the black frame is prepared and stored in advance in the storage unit 22 or the like.

  When the control unit 21 (job processing control unit 25) of the printer controller 20 receives a color correction request from the image forming apparatus 30 (S101), information on the paper type to be subjected to color correction, color information on color patches and layout information And the like are generated and transmitted to the image data processing unit 26.

  Next, the control unit 21 (image data processing unit 26) refers to the table stored in advance in the storage unit 22 to specify the width of the black frame according to the distance corresponding to the paper type of the color correction target (S102) For each color patch, a black frame of the width specified above is arranged around the color patch, and a color patch image with black frame is generated (S103). Then, when the generation of the color patch image with black frame is completed for all color patches (Yes in S104), the control unit 21 (RIP unit 27) performs color correction in which the generated color patch image with black frame is arranged according to the layout information The page image of the for-use chart is generated (S105). At that time, as a result of arranging the black frame, if the black patch with color frame image does not fit on one line, it is placed on the next line, and if it does not fit on one page, it is placed on the next page.

  Next, the control unit 21 (image data processing unit 26) determines, as necessary, whether the number of page images generated in S105 exceeds the limited number of pages specified in advance for the color correction chart. (S106), if not exceeded, the process skips to S109. On the other hand, when the number of restricted pages is exceeded, the control unit 21 (image data processing unit 26) displays a confirmation screen as to whether or not to execute color correction on the panel operation unit 34 of the image forming apparatus 30 (printer unit in the printer controller 20). In the case of including it, it is displayed on the display unit or the like to prompt the user to judge whether or not to execute the color correction (S107).

  If it is determined that the color correction is not to be performed (No in S108), the color correction processing is ended. If it is determined that the color correction is to be performed (Yes in S108), the control unit 21 (job processing control unit 25) The data of the page image of the generated color correction chart is transmitted to the image forming apparatus 30, and the printing and color measurement of the color correction chart are instructed (S109).

  When the image forming apparatus 30 receives data of the page image of the color correction chart, the printing unit 35 prints the color correction chart, and the inline sensor 36 measures the color patches of the color correction chart, The control unit 31 transmits the colorimetric data to the printer controller 20. The control unit 21 (job processing control unit 25) of the printer controller 20 performs color correction such as updating a color conversion table so that the measured color falls within a predetermined color gamut based on the received colorimetric data. .

  FIG. 8 is an example of a color correction chart printed by the above procedure. As shown in FIG. 8, a plurality of color patches 41 are arranged on the color correction chart 40. However, the influence of irregular reflection on adjacent color patches or paper is substantially around all the color patches 41. A black frame 42 having a width of, for example, 20 mm is formed. As a result, accurate colorimetric data can be acquired, and highly accurate color correction can be performed.

  Next, a color correction chart creation control program, an image forming apparatus, and a color correction chart creation method according to a second embodiment of the present invention will be described with reference to FIG. 9 to FIG. FIGS. 9 to 11 are flowcharts showing the operation of the printer controller, and FIG. 12 is an example of a table for correlating patch colors with black frame widths. FIG. 13 is a diagram for explaining the influence of diffuse reflection, and FIGS. 14 and 15 are diagrams showing an example of a color correction chart.

  In the first embodiment described above, black frames of the same width are arranged around all color patches, but if black frames of the same width are simply arranged around all color patches, a color having a small influence of irregular reflection In the patch, the size of the black frame becomes larger than necessary, and the number of pages of the color correction chart increases in order to arrange a predetermined number of color patches, and the ink is wasted. On the other hand, in the case of a color patch in which the influence of diffuse reflection is large, the size of the black frame becomes insufficient, so that the influence of the diffuse reflection can not be sufficiently suppressed although the black frame is arranged. Therefore, in the present embodiment, the width of the black frame is changed in accordance with the color of the color patch so that irregular reflection around the color patch can be effectively suppressed.

  In that case, the configuration of each device of the printing system is the same as that of the first embodiment described above, but the influence of the plurality of representative colors for each paper type and the peripheral irregular reflections on the storage unit 22 of the printer controller 20 is substantially The control unit 21 (the image data processing unit 26) refers to the table and stores the table that associates the distance with the distance that is lost as a representative color, and the representative color closest to the color of the color patch in the paper type of the color correction target. The width of the black frame is specified from the distance corresponding to, and a black frame image is generated around the color patch with the specified width.

  Hereinafter, an example of the operation of the printer controller 20 will be described. The CPU 21a executes the processing of each step shown in the flowcharts of FIGS. 9 to 11 by developing the color correction chart creation control program stored in the ROM 21b or the storage unit 22 on the RAM 21c and executing it. The control unit 31 of the image forming apparatus 30 automatically determines the necessity of color correction by counting the number of sheets for color printing, the use time of the apparatus, and the like, and determines that the color correction is necessary. In this case, it is assumed that a color correction request is sent to the printer controller 20. Further, it is assumed that a table in which the plurality of representative colors for each paper type are associated with the above-described distance is stored in the storage unit 22 in advance.

  When the control unit 21 (job processing control unit 25) of the printer controller 20 receives a color correction request from the image forming apparatus 30 (S201), information on the paper type to be subjected to color correction, color information on color patches and layout information And the like are generated and transmitted to the image data processing unit 26.

  Next, the control unit 21 (image data processing unit 26) reads a table corresponding to the paper type to be subjected to color correction from the storage unit 22 (S202). Then, the control unit 21 (image data processing unit 26) refers to the read table, and for each color patch, according to the distance corresponding to the representative color closest to the color of the color patch adjacent to the color patch. The width of the black frame is specified, and a black frame of the specified width is arranged around each color patch, and a color patch image with black frame is generated (S203). Details of this step will be described later. Then, this process is performed on all color patches (S204).

  Thereafter, as in the first embodiment, the control unit 21 (RIP unit 27) generates a page image of a color correction chart in which the black-framed color patch image generated in S203 is arranged according to the layout information (S205). At that time, as a result of arranging the black frame, if the black patch with color frame image does not fit on one line, it is placed on the next line, and if it does not fit on one page, it is placed on the next page.

  Next, the control unit 21 (image data processing unit 26) determines, as necessary, whether the number of page images generated in S205 exceeds the limited number of pages designated in advance for the color correction chart. (S206), if not exceeded, skip to S209. On the other hand, when the number of restricted pages is exceeded, the control unit 21 (image data processing unit 26) displays a confirmation screen as to whether or not to execute color correction on the panel operation unit 34 of the image forming apparatus 30 When provided, the display unit is displayed on the display unit or the like to prompt the user to determine whether or not to execute color correction (S207).

  If it is determined that the color correction is not to be performed (No in S208), the color correction processing is ended, and if it is determined that the color correction is to be performed (Yes in S208), the control unit 21 (job processing control unit 25) The data of the page image of the generated color correction chart is transmitted to the image forming apparatus 30, and the printing and color measurement of the color correction chart are instructed (S209).

  When the image forming apparatus 30 receives data of the page image of the color correction chart, the printing unit 35 prints the color correction chart, and the inline sensor 36 measures the color patches of the color correction chart, The control unit 31 transmits the colorimetric data to the printer controller 20. The control unit 21 (job processing control unit 25) of the printer controller 20 performs color correction such as updating a color conversion table so that the measured color falls within a predetermined color gamut based on the received colorimetric data. .

  Next, the generation step of the black framed color patch image in S203 will be described. First, the case of arranging a black frame having the same width in the main scanning direction and the sub scanning direction in color measurement will be described with reference to FIG.

  First, the control unit 21 (image data processing unit 26) refers to the color correction chart creation instruction information acquired from the job processing control unit 25 and is adjacent to the color patch to be measured in the sub-scanning direction A color patch is specified, and the color of the color patch is extracted (S301). Then, the control unit 21 (image data processing unit 26) extracts the distance (d1) corresponding to the RGB value closest to the extracted color with reference to the table read in S202 (S302). The table is configured, for example, as shown in FIG. 12, and RGB values and distances are associated with each paper type to be subjected to color correction. The above distance is a distance substantially eliminating the influence of diffuse reflection at adjacent color patches as shown in FIG. 13, and since this distance is different between the main scanning direction and the sub scanning direction, The distance in the scanning direction and the distance in the sub-scanning direction are described. The color patches adjacent in the sub-scanning direction may be color patches adjacent in one direction in the sub-scanning direction, or may be color patches adjacent in both directions. When color patches adjacent in both directions are used, respectively Among the distances corresponding to the RGB values closest to the color of the color patch, the larger one can be used.

  Next, the control unit 21 (image data processing unit 26) specifies a color patch adjacent in the main scanning direction for the color patch of the color measurement target as described above, and extracts the color of the color patch ( S303). Then, referring to the table read in S202, the distance (d2) corresponding to the RGB value closest to the extracted color is extracted (S304). Similarly to the above, the color patches adjacent in the main scanning direction may be color patches adjacent in one direction in the main scanning direction, or may be color patches adjacent in both directions. In this case, the larger one of the distances corresponding to the RGB value closest to the color of each color patch can be used.

  Next, the control unit 21 (image data processing unit 26) compares d1 and d2 (S305), and sets the width of the black frame to d1 when d1 is d2 or more (S306), and d1 is less than d2 In the case, the width of the black frame is set to d2 (S307). Then, a black frame having a set width is arranged around each color patch, and a color patch image with black frame is generated (S308).

  Next, FIG. 12 is referred to in the case where black frames having different widths in the main scanning direction and the sub scanning direction in color measurement are arranged (the width is changed between the portion facing in the main scanning direction and the portion facing in the sub scanning direction). To explain.

  First, similarly to the above, the control unit 21 (image data processing unit 26) extracts the color of the color patch adjacent in the sub-scanning direction with respect to the color patch of the color measurement target (S401). Then, the distance (d1) corresponding to the RGB value closest to the extracted color is extracted (S402). In addition, the color of the color patch adjacent in the main scanning direction is extracted with respect to the color patch to be measured (S403), and the table is referenced to obtain the distance (d2) corresponding to the RGB value closest to the extracted color. It extracts (S404).

  Next, the control unit 21 (image data processing unit 26) sets the width of the black frame in the sub-scanning direction to d1 and sets the width of the black frame in the main scanning direction to d2 (S405). Then, a black frame having a set width is arranged around each color patch, and a color patch image with black frame is generated (S406).

  FIG. 14 is an example of a color correction chart printed according to the flowchart of FIG. 10, and FIG. 15 is an example of a color correction chart printed according to the flowchart of FIG. As shown in FIGS. 14 and 15, a plurality of color patches 41 are arranged on the color correction chart 40, and for color patches having a small influence of diffuse reflection around, for example, a black frame having a width of 20 mm is used. For a color patch that is formed (black frame width in the figure: small) and the influence of diffuse reflection at the periphery is moderate, for example, a black frame with a width of 30 mm is formed (black frame width in the figure: middle) For a color patch having a large influence of diffuse reflection, for example, a black frame having a width of 40 mm is formed (black frame width in the figure: large). As a result, it is possible to create a color correction chart capable of sufficiently suppressing the influence of diffuse reflection without unnecessarily increasing the number of pages of the color correction chart, and to acquire accurate colorimetric data, so that highly accurate colors can be obtained. Correction is possible.

  In the above embodiment, the width of the black frame is set based on the color of the color patch adjacent in the sub scanning direction or the main scanning direction (that is, the width of the black frame is equal to the opposing side of the color patch). The width of the black frame is set based on the color of the adjacent color patch for each of the sub-scanning direction and the reverse direction (or the main scanning direction and the reverse direction) (ie, the black frame on opposite sides of the color patch) Change the width of the

  In the above embodiment, the width of the black frame is set in consideration of the color of the color patch adjacent to the color patch to be measured, but the color of the color patch two or more ahead in the sub-scanning direction and / or the main scanning direction And the width of the black frame may be set.

  Further, in the above embodiment, the width of the black frame is set based on the color of the color patch adjacent to the color patch to be measured, but the color of the color patch is likely to be affected by ambient diffuse reflection (color saturation Because some colors have low lightness and some colors are not susceptible to ambient diffuse reflection (colors with high saturation and lightness), the width of the black frame is set based on the color of the color patch itself to be measured You can also In that case, it is not necessary to identify adjacent color patches in the sub-scanning direction and the main scanning direction, or to extract the color of the color patch. The width of the black frame may be set according to the distance corresponding to the closest representative color.

  Next, a color correction chart creation control program, an image forming apparatus, and a color correction chart creation method according to a third embodiment of the present invention will be described with reference to FIG. FIG. 16 is a flowchart showing the operation of the printer controller.

  In the first and second embodiments described above, a black frame of a desired width is arranged around the color patch, but a black frame of a predetermined width can not be arranged depending on the spacing of the color patch. In the case of a color patch having a large influence, the size of the black frame becomes insufficient, which causes a problem that although the black frame is arranged, the influence of diffuse reflection can not be reliably suppressed. Therefore, in the present embodiment, when a black frame having a width corresponding to the distance corresponding to the color of the color patch adjacent to the color patch to be measured can not be arranged, the color patch interval is changed to influence the peripheral diffuse reflection. Make it possible to suppress effectively.

  In that case, the configuration of each device of the printing system is the same as that of the first embodiment described above, but the influence of the plurality of representative colors for each paper type and the peripheral irregular reflections on the storage unit 22 of the printer controller 20 is substantially The control unit 21 (the image data processing unit 26) refers to the table and stores the table that associates the distance with the distance that is lost as a representative color, and the representative color closest to the color of the color patch in the paper type of the color correction target. The width corresponding to the distance is specified, it is judged whether the black frame can be arranged around the color patch with the specified width, and if it is judged that the black frame can not be arranged, the color patch interval is expanded.

  Hereinafter, an example of the operation of the printer controller 20 will be described. The CPU 21a executes the processing of each step shown in the flowcharts of FIGS. 16 and 17 by developing the color correction chart creation control program stored in the ROM 21b or the storage unit 22 on the RAM 21c and executing it. The control unit 31 of the image forming apparatus 30 automatically determines the necessity of color correction by counting the number of sheets for color printing, the use time of the apparatus, and the like, and determines that the color correction is necessary. In this case, it is assumed that a color correction request is sent to the printer controller 20. Further, it is assumed that a table in which the plurality of representative colors for each paper type are associated with the above-described distance is stored in the storage unit 22 in advance. Further, the overall operation (the flow chart of FIG. 9) of the printer controller 20 is the same as that of the second embodiment described above, so the description will be omitted.

  The case of arranging a black frame having the same width in the main scanning direction and the sub scanning direction will be described with reference to FIG.

  As in the second embodiment, the control unit 21 (image data processing unit 26) extracts the color of the color patch adjacent in the sub-scanning direction with respect to the color patch of the color measurement target (S501). The distance (d1) corresponding to the RGB value closest to the extracted color is extracted with reference to the table stored in advance (S502). Here, in the present embodiment, the control unit 21 (image data processing unit 26) refers to the layout information included in the creation instruction information of the color correction chart transferred from the job processing control unit 25, and the color measurement target The distance between the color patch and the color patch adjacent in the sub-scanning direction is determined, and the distance is compared with the distance (d1) extracted in the above step (S503). As a result, when the spacing between color patches is less than the distance (d1) (No in S503), adjacent color patches are moved in the sub-scanning direction such that the spacing between color patches is equal to or greater than the distance (d1). (S504). If there are color patches further adjacent to the adjacent color patch, the color patch is also moved in the sub-scanning direction.

  Next, the control unit 21 (image data processing unit 26) specifies a color patch adjacent to the color patch to be measured in the main scanning direction, and extracts the color of the color patch (S505). Then, with reference to the table stored in advance in the storage unit 22, the distance (d2) corresponding to the RGB value closest to the extracted color is extracted (S506). Then, in the same manner as described above, the control unit 21 (image data processing unit 26) refers to the layout information to obtain an interval between a color patch to be measured and a color patch adjacent in the main scanning direction. The distance (d2) extracted in the above step is compared (S507). As a result, when the spacing between color patches is less than the distance (d2) (No in S507), adjacent color patches are moved in the main scanning direction such that the spacing between color patches is equal to or greater than the distance (d2). (S508). If there are color patches further adjacent to the adjacent color patch, the color patch is also moved in the main scanning direction.

  Next, the control unit 21 (image data processing unit 26) compares d1 and d2 (S509), and sets the width of the black frame to d1 when d1 is d2 or more (S510), and d1 is less than d2 In the case, the width of the black frame is set to d2 (S511). Then, a black frame having a set width is arranged around each color patch, and a color patch image with black frame is generated (S512). When arranging black frames having different widths in the main scanning direction and the sub scanning direction, set the width of the black frame in the sub scanning direction to d1, set the width of the black frame in the main scanning direction to d2, and set each color A black frame with a set width may be placed around the patch to generate a color patch image with a black frame.

  As described above, when the black frame having a width corresponding to the distance corresponding to the color of the color patch adjacent to the color patch to be measured can not be arranged, the influence of the irregular reflection around is assured by changing the interval of the color patch. It is possible to create a color correction chart that can be suppressed, to obtain accurate colorimetric data, and to perform color correction with high accuracy.

  The present invention is not limited to the above-described embodiment, and the configuration and control of the printing system and each device can be appropriately changed without departing from the spirit of the present invention.

  For example, in the above embodiment, the inline sensor 36 is installed in the sheet conveyance path between the fixing unit of the printing unit 35 and the discharge tray, but the inline sensor 36 may be provided in the vicinity of the intermediate belt it can. In that case, each color patch of the color correction chart on which an image is formed on the intermediate belt can be measured and output as colorimetric data.

  In the above embodiment, the color measurement is performed using the in-line sensor 36 of the image forming apparatus 30. However, the color measurement may be performed by the color measuring device connected to the scan unit 33 of the image forming apparatus 30 or the printing system. You may

  Further, in each of the above-described embodiments, the distance that substantially eliminates the influence of diffuse reflection in the periphery is specified as the width of the black frame. Further, in the state where the black frame-attached color patch image is disposed in the page, when the gap is open, the gap may be filled with black.

  The present invention relates to a color correction chart creation control program for controlling creation of a color correction chart, a recording medium recording the color correction chart creation control program, an image forming apparatus for printing the color correction chart, and the image forming apparatus Can be used in a method of creating a chart for color correction in a system including:

10 client device 11 control unit 11a CPU
11b ROM
11c RAM
12 storage unit 13 network I / F unit 14 display unit 15 operation unit 16 OS
17 Document Creation Application 18 Printer Driver 20 Printer Controller 21 Controller 21a CPU
21b ROM
21c RAM
22 storage unit 23 network I / F unit 24 printer I / F unit 25 job processing control unit 26 image data processing unit 27 RIP unit 30 image forming apparatus 31 control unit 31 a CPU
31b ROM
31c RAM
32 controller I / F unit 33 scanning unit 34 panel operation unit 35 printing unit 36 in-line sensor 40 color correction chart 41 color patch 42 black frame

Claims (17)

A color correction chart creation control program that operates on a control device that instructs an image forming apparatus including a printing unit and a color measurement unit to print.
When the colorimetry unit of the image forming apparatus measures a predetermined color patch, the distance information substantially eliminates the influence of diffuse reflection of colorimetry light in the color patch adjacent to the predetermined color patch ,
In the controller,
When instructing printing of color correction chart for performing color correction of the image forming apparatus, on the basis of the distance information previously stored in the storage unit, each of the color patches to be arranged in the color correction chart The first process to identify the width of the black frame formed around
A second process of generating a black framed color patch image in which a black frame of the specified width is formed around each of the color patches;
A third process of generating a print image of the color correction chart in which the black framed color patch image is arranged by a RIP (Raster Image Processor) unit;
Transmitting data of the print image to the image forming apparatus to execute printing of the color correction chart and a fourth process of instructing color measurement of each color patch;
A color correction chart creation control program characterized in that. The storage unit stores the distance information for each paper type,
In the first process,
The distance information corresponding to the paper type for printing the color correction chart is extracted from the storage unit, and the width of the black frame is specified based on the extracted distance information.
A color correction chart creation control program according to claim 1, characterized in that: The storage unit stores, for each paper type, a table that associates a plurality of representative colors with distance information for each of the representative colors.
In the first process,
For each of the color patches, the color of the color patch adjacent to the color patch is specified, and a table corresponding to a paper type for printing the color correction chart is referred to, and the representative closest to the specified color is referred to Extracting distance information corresponding to a color, and specifying a width of the black frame based on the extracted distance information;
A color correction chart creation control program according to claim 1, characterized in that: In the first process,
The distance information extracted for color patches adjacent in the sub-scanning direction in color measurement is compared with the distance information extracted for color patches adjacent in the main scanning direction in color measurement, and the larger distance information is obtained. Specify the width of the black frame based on
4. The color correction chart creation control program according to claim 3, characterized in that: In the first process,
The width of the portion of the black frame facing in the sub-scanning direction is specified based on the distance information extracted with respect to the color patch adjacent in the sub-scanning direction in color measurement, and for the color patch adjacent in the main scanning direction in color measurement. Identifying the width of the portion of the black frame facing in the main scanning direction based on the extracted distance information,
4. The color correction chart creation control program according to claim 3, characterized in that: In the third process,
If the spacing between adjacent color patches is smaller than the specified width, the spacing is increased beyond the specified width,
The color correction chart creation control program according to any one of claims 1 to 5, wherein In the third process,
If the plurality of black framed color patch images do not fit on one line, place them on the next line, and if they do not fit on one page, place them on the next page,
The color correction chart creation control program according to claim 6, characterized in that: In the third process,
If the number of pages of the color correction chart exceeds the predetermined number of pages, a screen for confirming whether to print the color correction chart is displayed on the own apparatus or the image forming apparatus, and an instruction to continue printing is given. Execute the fourth process if the
8. The color correction chart creation control program according to claim 7, characterized in that:   An image forming apparatus including a printing unit, a color measurement unit, and a storage unit.
  When the colorimetry unit of the image forming apparatus measures a predetermined color patch, the distance information substantially eliminates the influence of diffuse reflection of colorimetry light in the color patch adjacent to the predetermined color patch ,
  When printing a color correction chart for performing color correction, a black frame formed around each color patch arranged in the color correction chart based on the distance information stored in advance in the storage unit An image data processing unit for specifying a width of the black patch and forming a black bordered color patch image in which the black border having the specified width is formed around each of the color patches;
  A RIP (Raster Image Processor) unit that generates a print image of the color correction chart in which the black framed color patch images are arranged;
  A job processing control unit that causes the printing unit to print the color correction chart and causes the color measurement unit to measure each color patch;
  An image forming apparatus characterized by The storage unit stores the distance information for each paper type,
The image data processing unit extracts distance information corresponding to a paper type on which the color correction chart is to be printed from the storage unit, and specifies the width of the black frame based on the extracted distance information.
The image forming apparatus according to claim 9, The storage unit stores, for each paper type, a table that associates a plurality of representative colors with distance information for each of the representative colors.
The image data processing unit identifies the color of a color patch adjacent to the color patch for each color patch, and refers to a table corresponding to a paper type on which the color correction chart is to be printed. Extracting distance information corresponding to a representative color closest to the identified color, and specifying a width of the black frame based on the extracted distance information;
The image forming apparatus according to claim 9 , The image data processing unit compares distance information extracted for color patches adjacent in the sub-scanning direction in color measurement with distance information extracted for color patches adjacent in the main scanning direction in color measurement. , Identifying the width of the black frame based on the larger distance information,
The image forming apparatus according to claim 11 , The image data processing unit identifies the width of the portion of the black frame facing in the sub-scanning direction based on the distance information extracted for the color patch adjacent in the sub-scanning direction in color measurement, and the main scanning direction in color measurement Identifying the width of the portion of the black frame facing in the main scanning direction based on the distance information extracted for the color patch adjacent to
The image forming apparatus according to claim 11 , When the distance between adjacent color patches is smaller than the specified width, the RIP unit enlarges the distance to the specified width or more to arrange the black framed color patch image.
The image forming apparatus according to any one of claims 9 to 13 , characterized in that: The RIP unit arranges the next line if the plurality of black framed color patch images do not fit on one line, and arranges it on the next page if it does not fit on one page.
The image forming apparatus according to claim 14 , characterized in that: When the number of pages of the color correction chart exceeds a predetermined number of pages, the image data processing unit causes the display to display a screen for confirming whether or not the color correction chart is to be printed.
The job processing control unit, when instructed to continue printing, causes the printing unit to print the color correction chart, and causes the color measurement unit to measure each color patch.
The image forming apparatus according to claim 15, wherein   A method for creating a chart for color correction in a printing system in which an image forming apparatus including a printing unit and a color measurement unit, and a control device that instructs the image forming apparatus to print are connected via a communication network.
  When the colorimetry unit of the image forming apparatus measures a predetermined color patch, the distance information substantially eliminates the influence of diffuse reflection of colorimetry light in the color patch adjacent to the predetermined color patch ,
  The controller is
  When instructing printing of a color correction chart for performing color correction of the image forming apparatus, each color patch arranged in the color correction chart based on the distance information stored in advance in the storage unit A first process for specifying the width of the black frame formed around the
  A second process of generating a black framed color patch image in which a black frame of the specified width is formed around each of the color patches;
  A third process of generating a print image of the color correction chart in which the black framed color patch image is arranged by a RIP (Raster Image Processor) unit;
  Performing a fourth process of transmitting data of the print image to the image forming apparatus;
  The image forming apparatus is
  The printing unit prints the color correction chart on the basis of the print image data, and the color measurement unit measures each color patch.
  A method of creating a chart for color correction characterized by

Images