Color Validation Apparatus, Color Validation Method and Computer-Readable Recording Medium

In accordance with a user operation, an apparatus obtains one or more designated positions on an image, the one or more designated positions being one or more positions at which each of one or more designated colors designated for printing of the image is to be printed. The apparatus generates a printing file for causing a printer to print a patch of each of the one or more designated colors on a sheet at a position corresponding to each of the one or more designated positions for the designated color. The apparatus performs color verification based on a colorimetry value on the sheet having the patch printed thereon at the position corresponding to each of the one or more designated positions and a target value for the designated color corresponding to the designated position.

The entire disclosure of Japanese Patent Application No. 2020-119014, filed on Jul. 10, 2020, is incorporated herein by reference in its entirety.

BACKGROUND

Technological Field

The present disclosure relates to a color verification apparatus, a color verification method, and a computer-readable recording medium, particularly, to a color verification apparatus, a color verification method, and a computer-readable recording medium, each of which uses colorimetry.

Description of the Related Art

In a printing industry, color verification is performed in order to maintain excellent printing quality. For example, in a colorimetry value detection system of Japanese Laid-Open Patent Publication No. 2019-100864, a guide rail is provided with a guide groove having a length or width formed along the longitudinal direction thereof, and is set on a printed material by a user such that a colorimetry position of the printed material or an object including the colorimetry position is positioned in the guide groove. Then, a manual colorimeter is moved along the guide groove of the guide rail in accordance with an operation by the user so as to perform measurement of a color (colorimetry) of the colorimetry position of the printed matter or the object including the colorimetry position (see paragraph 0018).

Japanese Laid-Open Patent Publication No. 2016-70697 discloses a measurement position presentation method including: a determination step of determining, based on printing image data, in advance a measurement position for measuring quality of a printed material on which an image is printed; a generation step of generating a measurement position presentation guide indicating the measurement position of the printed material based on the printing image data; and a presentation step of presenting the measurement position by disposing a measurement position presentation guide on the printed material. In the generation step, a process of cutting out a portion corresponding to the measurement region of the measurement position presentation guide is performed.

SUMMARY

In order to specify a position to be subjected to the colorimetry for color verification, in Japanese Laid-Open Patent Publication No. 2019-100864, the user moves the manual colorimeter along the guide groove of the guide rail. On the other hand, Japanese Laid-Open Patent Publication No. 2016-70697 uses a special mechanism for cutting out the portion corresponding to the measurement region of the measurement position presentation guide. Therefore, for the color verification, a demand arises in a system that can designate a colorimetry position by a simple operation without requiring a special mechanism.

To achieve at least one of the abovementioned objects, according to an aspect of the present invention, a color verification apparatus reflecting one aspect of the present invention comprises a hardware processor. In accordance with a user operation, the hardware processor obtains one or more designated positions on an image, the one or more designated positions being one or more positions at which each of one or more designated colors designated for printing of the image is to be printed, the hardware processor generates a printing file for causing a printer to print a patch of each of the one or more designated colors on a sheet at a position corresponding to each of the obtained one or more designated positions for the designated color, and the hardware processor performs color verification based on a colorimetry value on the printed sheet at the position corresponding to each of the one or more designated positions and a target value for the designated color corresponding to the designated position.

To achieve at least one of the abovementioned objects, according to an aspect of the present invention, a color verification method reflecting one aspect of the present invention comprises: in accordance with a user operation, obtaining one or more designated positions on an image, the one or more designated positions being one or more positions at which each of one or more designated colors designated for printing of the image is to be printed; generating a printing file for causing a printer to print a patch of each of the one or more designated colors on a sheet at a position corresponding to each of the obtained one or more designated positions for the designated color; and performing color verification based on a colorimetry value on the printed sheet at the position corresponding to each of the one or more designated positions and a target value for the designated color corresponding to the designated position.

To achieve at least one of the abovementioned objects, according to an aspect of the present invention, a computer-readable recording medium reflecting one aspect of the present invention is provided, the computer-readable recording medium being a computer-readable recording medium that stores a program for causing a computer to perform the above-described color verification method.

DETAILED DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments will be described with reference to figures. In the description below, the same parts and components are denoted by the same reference characters. Their names and functions are also the same. Therefore, they will not be described repeatedly. First, terms used in the embodiments will be described.

The term “spot color” refers to a color having a special meaning for a user of a printed material, such as a logotype or a brand color that is a color representing a brand. The spot color is also referred to as “specific color”. The spot color is one example of a “designated color”, and the designated color is not limited to the spot color.

The term “colorimetry” refers to measurement of a color of an image printed by a printer on a medium such as a sheet. In a color verification process, the printer prints a color patch, and a colorimeter measures the color of the printed color patch.

The term “color verification” indicates a process of evaluating whether or not appropriate color reproducibility is realized by a printer. The color reproducibility means that even when images are formed (drawn or printed) on media (sheets or the like) by any printer, the formed images exhibit the same brightness or hue.

In the color verification, a colorimetry value is compared with a target value, and the color verification is performed based on a difference (hereinafter, referred to as “color difference”) therebetween obtained by the comparison. More specifically, in the color verification, each of the colorimetry value and the target value is indicated by a Lab value indicating coloration, for example. For example, in the color verification, when a color difference value quantitatively indicating a color difference, such as a difference in Lab value between the colorimetry value and the target value, does not exceed a permissible range, “Passed” (success) is output as a color verification result. When the color difference value exceeds the permissible range, “Failed” (failure) is output as the color verification result. It should be noted that the color value is not limited to the Lab value, and may be a Munsell value (HVC).

FIG. 1is a configuration diagram of a system according to the present embodiment. Referring toFIG. 1, a system1includes: an image forming apparatus100installed in, for example, a printing company; and an information processing apparatus200to which a colorimeter500having a color sensor can be connected. Image forming apparatus100, colorimeter500, and information processing apparatus200communicate with one another via a network600in the printing company. System1further includes a server300connected to a network400. Network600is connected to network400via a communication device (such as a router or a switch) not shown in the figure. Therefore, in system1, image forming apparatus100, colorimeter500, information processing apparatus200, and server300can communicate with one another via networks400,600.

It should be noted that colorimeter500may be connected to network600or may be included in image forming apparatus100. Further, network400includes a network external to the printing company or a network internal to the company. Further, each of networks400,600includes a wired or wireless network. Further, networks400and600are shown as different networks inFIG. 1, but may be the same network.

In the present embodiment, server300mainly performs color verification for image forming apparatus100, but the apparatus for performing the color verification is not limited to server300and may be information processing apparatus200. Further, when image forming apparatus100is configured to include a server or information processing apparatus therein, the server or information processing apparatus included therein may perform the color verification.

Typically, a general-purpose computer such as a personal computer is applied to information processing apparatus200. Although information processing apparatus200is shown as a stationary type information processing apparatus inFIG. 1, information processing apparatus200may be a portable type information processing apparatus such as a tablet type or laptop type information processing apparatus.

(a1. Hardware Configuration of Image Forming Apparatus100)

FIG. 2is a schematic diagram showing an internal configuration of image forming apparatus100. Image forming apparatus100is illustrated as a printer, a copy machine, or an MFP (Multi-Function Peripheral), which is a composite machine of the printer and the copy machine. Functions included in image forming apparatus100are not limited to those of the printer and the copy machine, and may further include functions such as those of a scanner and a facsimile. Image forming apparatus100can execute a print job, a copy job, a scan job, a facsimile job, and the like. It should be noted that image forming apparatus100may be provided as a printing apparatus that provides only the printer function.

Image forming apparatus100includes an image forming unit152, an image scanning unit173, an automatic document feeding unit13, a sheet supplying unit14, a conveyance path15, a reverse conveyance path17, an ejection roller18, and an operation panel170. Image forming apparatus100further includes a controller150that controls image forming apparatus100.

Automatic document feeding unit13automatically feeds a document placed on a document table, to a scanning position of image scanning unit173. Image scanning unit173optically scans an image of the document fed by automatic document feeding unit13, and generates image data. Sheet supplying unit14includes a sheet supplying roller113and a sheet supplying cassette142. Sheets P are accommodated in sheet supplying cassette142. Sheet supplying roller113sends a sheet P upward along conveyance path15. Reverse conveyance path17is used for double-side printing; however, reverse conveyance path17may be used for single-side printing.

Based on the image data generated by image scanning unit173or image data obtained from a print job, image forming unit152forms an image on sheet P supplied by sheet supplying unit14. For example, image forming apparatus100can receive a print job from an external apparatus such as information processing apparatus200or server300.

Image forming unit152has a so-called printer configuration. More specifically, image forming unit152includes an intermediate transfer belt101, paper stop rollers102,103, a yellow image forming unit104Y, a magenta image forming unit104M, a cyan image forming unit104C, a black image forming unit104K, an image density sensor105, primary transferring devices111, a secondary transferring device115, and a fixing device120. Fixing device120includes a heating roller121and a pressing roller122.

Intermediate transfer belt101is an endless belt member. Both end portions of intermediate transfer belt101are supported by paper stop rollers102,103. Image forming units104Y,104M,104C,104K for the respective colors and image density sensor105are disposed below intermediate transfer belt101.

Image forming unit104Y includes a photoconductor drum106, a charging device107, an exposure device108, a developing device109, and a cleaning device110. Charging device107, exposure device108, developing device109, and cleaning device110are disposed around photoconductor drum106. It should be noted that each of image forming units104M,104C,104K has the same hardware configuration as that of image forming unit104Y.

Ejection roller18is disposed on the downstream side with respect to fixing device120in conveyance path15. Sheet ejection roller18sends, to a horizontal conveyance unit290, sheet P ejected from image forming units104Y,104M,104C,104K. A plurality of horizontal conveyance rollers291included in horizontal conveyance unit290convey sheet P ejected from ejection roller18, to an external tray271attached to image forming apparatus100.

Next, an operation of image forming apparatus100will be described. Image forming apparatus100generates respective pieces of image data for the colors in accordance with a document scanned by image scanning unit173or in accordance with a print job. The generated pieces of image data for the colors are sent to corresponding image forming units104Y,104M,104C,104K. Image forming units104Y,104M,104C,104K for the colors charges and exposes respective photoconductor drums106based on the respective pieces of image data, thereby forming electrostatic latent images. Further, image forming units104Y,104M,104C,104K develop the formed electrostatic latent images to form toner images.

The formed toner images are sequentially transferred to and overlaid on intermediate transfer belt101by respective primary transferring devices111. At the same time, a sheet P is sent upward from sheet supplying unit14along conveyance path15, and the toner images overlaid on intermediate transfer belt101are synchronously transferred to sheet P by secondary transferring device115. Sheet P having the toner images thereon is further conveyed to fixing device120, and is heated and pressed by fixing device120. Thus, the toner images are fixed to sheet P. Sheet P having the toner images fixed thereon is ejected to horizontal conveyance unit290by ejection roller18. In the case where colorimeter500is included in image forming apparatus100, colorimeter500performs colorimetry by scanning sheet P before printed sheet P is ejected.

It should be noted that in the case of single-side printing, sheet P having the toner images fixed on its front surface by fixing device120is ejected without a further process of image forming. In the case of double-side printing, the sheet is conveyed again to secondary transferring device115via reverse conveyance path17to form an image on its rear surface, and is then ejected.

(a2. Module Configuration of Image Forming Apparatus100)

FIG. 3is a diagram schematically showing an exemplary module configuration of image forming apparatus100. Referring toFIG. 3, image forming apparatus100includes: a controller150including a CPU (Central Processing Unit) including a hardware processor circuitry; a storage unit160that stores a program and data; an operation panel170; a communication I/F (interface)156that communicates with server300or information processing apparatus200via network600; a communication circuit175; various types of sensors177; and various types of processing units.

Storage unit160includes a ROM (Read Only Memory), a RAM (Random Access Memory), a non-volatile memory, and the like, each of which stores a program to be executed by the CPU of controller150as well as data. The RAM is also provided as a work area when a program is executed by the CPU of controller150.

Operation panel170includes: a presentation unit171including a display; and an operation unit172that is operated by a user to input information to image forming apparatus100. Here, operation panel170may be provided as a touch panel in which presentation unit171and operation unit172are formed in one piece.

Communication I/F156includes a circuit such as a NIC (Network Interface Card). Communication I/F156includes a data communication unit157that conforms to a communication standard such as Wi-Fi (registered trademark). Data communication unit157includes: a transmitting unit158that transmits data to external apparatuses including server300and information processing apparatus200via the networks; and a receiving unit159that receives data from the external apparatuses including server300and information processing apparatus200via the networks. Communication circuit175can include a communication circuit that conforms to a communication standard such as NFC (Near Field Communication) or USB (Universal Serial Bus). Each of communication I/F156and communication circuit175receives a print job70.

The various types of processing units described above include: an image processing unit151that generates image data of each color based on document data scanned from a document or print job70; an image forming unit152; a storage unit153, such as a hard disk, that stores various types of data including image data; a facsimile control unit155that controls a facsimile circuit (not shown); an image scanning unit173; and a data reader/writer174to which a recording medium176is detachably attached.

Data reader/writer174has: a circuit that reads out a program or data from recording medium176attached thereto; and a circuit that writes data to recording medium176.

Image processing unit151generates image data of each color from print job70. More specifically, print job70includes PJL data, PDL (page description language) data, and a user ID that identifies a user having provided print job70. The PJL data is an instruction that does not directly affect the PDL data, and includes commands for functions such as stapling and punching. Image processing unit151loads the PDL data of print job70as bitmap data on the RAM of storage unit160. In accordance with the bitmap data (PDL data) loaded by image processing unit151, image forming unit152performs a printing process for each color onto sheet P. Also, image processing unit151loads, as bitmap data, image data scanned from a document by image scanning unit173. In accordance with the bitmap data loaded with regard to the document, image forming unit152performs a printing process for each color on sheet P.

(a3. Hardware Configuration of Server300)

FIG. 4is a diagram schematically showing an exemplary hardware configuration of server300. Referring toFIG. 4, server300includes: a controller30including a CPU including a hardware processor circuitry; a storage unit34; and a network controller35. Further, server300includes an R/W (abbreviation of “reader/writer”)34-1. A recording medium34-2is detachably attached to R/W34-1. R/W34-1reads and writes data and a program from and into attached recording medium34-2under control of controller30.

Storage unit34includes a ROM31, a RAM32, and a hard disk drive (HDD)33, each of which stores a program to be executed by the CPU of controller30and data. RAM32includes: an area that stores various types of information; and a work area when a program is executed by the CPU of controller30. HDD33stores a color verification program36. Network controller35includes a circuit, such as a NIC, that controls communication between server300and another apparatus via network400.

(a4. Hardware Configuration of Information Processing Apparatus200)

FIG. 5is a diagram schematically showing an exemplary hardware configuration of information processing apparatus200. Referring toFIG. 5, information processing apparatus200includes: a controller20including a CPU including a hardware processor circuitry; a display23; an operation key25that is operated by a user to input information to information processing apparatus200; a storage unit26; a communication controller27; and a communication circuit29. Further, information processing apparatus200includes an R/W (abbreviation of “reader/writer”)26-1. A recording medium26-2is detachably attached to R/W26-1. R/W26-1reads and writes data and a program from and into attached recording medium26-2under control of controller20. Storage unit26includes a ROM21, a RAM22, and a memory28, each of which stores a program to be executed by CPU20and data. Memory28includes a hard disk device. Display23and operation key25may be provided as an operation panel24such as a touch panel in which display23and operation key25are formed in one piece. Communication controller27includes a communication circuit, such as an NIC or a LAN circuit, that controls communication between information processing apparatus200and another apparatus via network600. Communication circuit29communicates with colorimeter500in accordance with a communication standard such as USB.

B. Configuration for Implementing Color Verification System

FIG. 6is a diagram schematically showing a module configuration of a color verification system according to the present embodiment. Referring toFIG. 6, controller30of server300implements a color verification unit37by executing a color verification program36. The color verification system is implemented when information processing apparatus200uses a browser201included in information processing apparatus200to exchange data with server300serving as a web server, more specifically, exchange data with color verification unit37. Here, browser201is included in information processing apparatus200; however, browser201may be included in image forming apparatus100. An environment provided by color verification unit37is not limited to server300, and may be implemented in information processing apparatus200or image forming apparatus100. Hence, when each of server300, information processing apparatus200, and image forming apparatus100has the modules included in controller30and the data (including the data stored in HDD33) inFIG. 6, each of server300, information processing apparatus200, and image forming apparatus100constitutes one embodiment of the “color verification apparatus”.

The data stored in HDD33includes: patch data331indicating a patch of each spot color; target value data332representing a target Lab value for each spot color; and a colorimetry job file340. Colorimetry job file340is generated and stored whenever a color verification job is executed in server300. A job identifier is assigned to colorimetry job file340in order to identify the file.

Colorimetry job file340includes job image data333, configuration data334, a colorimetry file335, a colorimetry result336, and a color verification result337. Job image data333indicates an image to be subjected to color verification, and includes an image that is based on image data obtained from print job70, for example Configuration data334includes data indicating one or more designated positions on the image indicated by job image data333, the one or more designated positions being one or more positions at which each of one or more specific colors designated for printing of the image is to be printed. Colorimetry file335corresponds to a printing file for causing printer140to print a patch of each of the one or more designated colors on a sheet P at a position corresponding to each of the one or more designated positions for the designated color. Colorimetry file335(printing file) can be converted into print job70by performing a predetermined process. Colorimetry result336includes a colorimetry value on printed sheet P at a position corresponding to each of the one or more designated positions. Color verification result337includes a result of color verification that is based on the colorimetry value on printed sheet P at the position corresponding to each of the one or more designated positions and a target value indicated by color target value data332and corresponding to the designated position.

Controller30includes: a browser I/F (abbreviation for “interface”)360that communicates with browser201of information processing apparatus200to exchange data; a color verification unit37; and a screen generation unit375. Screen generation unit375generates a screen (screen data) that can be presented by browser201in accordance with an output from color verification unit37. The generated screen is transmitted to browser201via browser I/F360. Browser201causes display23of operation panel24to present the screen received from server300. Screen generation unit375can generate screen data using, for example, HyperText Markup Language (HTML) for web page screens.

Color verification unit37includes: a configuration obtainment unit370that obtains configuration data334; a colorimetry processing unit371; and a report creation unit374that creates a report of a result of color verification. Colorimetry processing unit371includes: a colorimetry file generation unit372that generates colorimetry file335; and a colorimetry result calculation unit373that calculates colorimetry result336. Configuration obtainment unit370is one embodiment of a “color position obtainment module” configured by executing color verification program36by the CPU of controller30. Colorimetry file generation unit372is one embodiment of “file generation module” configured by executing color verification program36by the CPU of controller30. Report creation unit374is one embodiment of a “report module” that outputs a result of color verification and that is configured by executing color verification program36by the CPU of controller30.

Referring toFIG. 6, colorimeter500optically scans the image printed on sheet P using a CCD (Charge Coupled Device)501, generates, from an output of CCD501, a colorimetry value that is based on a value corresponding to a coloration of each pixel at a scanning position, and transmits the generated colorimetry value to information processing apparatus200via communication circuit502.

C. Process and Exemplary Presentation Screen

By operating operation panel24, the user can perform color verification in a manner interactive with color verification unit37of server300via a screen presented on display23by browser201. Such a process regarding the interactive manner is implemented by controller20of information processing apparatus200operating as browser201, and controller30of server300operating as browser I/F201, color verification unit37, and screen generation unit375. Hereinafter, a color verification process for a spot color will be described; however, the target for the color verification is not limited to the spot color, and another color may be the target for the verification. Each ofFIGS. 7 to 9 and 13 to 15is a diagram showing an exemplary browser screen presented by browser201. Each ofFIGS. 16 to 20is a flowchart of a process according to the embodiment of the present invention. Referring toFIGS. 7 to 15, the processes of the color verification system will be described in accordance with the flowcharts ofFIGS. 16 to 20.

Referring toFIG. 16, the following describes creation of target configuration data334(hereinafter, also referred to as target configuration). Controller30operates as configuration obtainment unit370to perform the process ofFIG. 16. First, controller30transmits screen data for a target configuration creation screen to information processing apparatus200. Browser201causes display23to present a screen (FIG. 7) that is based on the received screen data (step S1).

The screen (FIG. 7) includes a spot color list73, a radio button79, and a window72that presents an image corresponding to an uploaded image. Spot color list73shows a list of spot colors that have been registered in advance and that are used to print a target image of the target. More specifically, spot color list73includes: a position identifier71that identifies a position corresponding to each of one or more spot colors in an image, each of the one or more spot colors being a candidate for colorimetry; a target value76for the spot color, target value76being indicated by a Lab value; and a permissible range77for color difference value. Position identifier71identifies a position, in the target image, at which a corresponding spot color is to be printed. Permissible range77is a type of threshold value. Permissible range77may be a range of values, or may be a single value. The user can set permissible range77by an operation via operation panel24.

From spot color list73, the user selects spot color(s)74intended to be subjected to the colorimetry (step S2). On this occasion, the user can also set permissible range77for each of the selected spot color(s). Further, the user operates an upload button of radio button79to upload a job image of an image to be printed using selected spot color(s)74(step S3). For example, image data obtained from print job70is presented in window72of the screen (FIG. 7).

When the user operates a position designation button of radio button79, controller30transmits data of a screen for designating colorimetry positions. Based on the received screen data, browser201causes display23to present a screen (FIG. 8) for designating the colorimetry positions (step S4).

The screen (FIG. 8) for designating the colorimetry positions is a screen for designating: one or more spot colors used (designated) by the user to print the image; and one or more positions on the image at which each of the spot colors is to be printed. More specifically, the screen (FIG. 8) has: a guidance81including a message for supporting a designation operation; a list82of the spot colors selected by the user in the screen (FIG. 7) for the target configuration creation; and a window83that presents the image of job image data333(step S5). In accordance with guidance81, the user performs an operation of: selectively designating the spot colors; and designating positions (colorimetry positions) to be subjected to the colorimetry for each of the spot colors.

Based on the user operation received on the screen (FIG. 8), controller30places patches84,85of the spot colors on the image of window83at the positions to be subjected to the colorimetry (steps S6to S100). More specifically, in accordance with the user operation received via the screen (FIG. 8), controller30determines whether or not the user has selected a spot color from spot color list82(step S6). While it is determined that the user has selected no spot color (NO in step S6), controller30repeats the determination of step S6. When controller30determines that the user has selected a spot color (YES in step S6), controller30generates a color patch for the selected spot color based on patch data331(step S7). Further, in accordance with the user operation received via the screen (FIG. 8), controller30determines whether or not the user has designated a position on the image of window83(step S8). While it is determined that no position has been designated (NO in step S8), controller30repeats the determination of step S8. On the other hand, when it is determined that the user has designated a position (YES in step S8), the patch generated in step S7is placed on the image of window83at the position designated by the user (step S9). More specifically, controller30causes display23to present the image, and obtains, as the designated position, the position designated by the operation of the user on the presented image. That is, controller30generates screen data in which the patch for the selected spot color is placed at the designated position on the image of window83, and transmits the screen data to information processing apparatus200. Browser201causes display23to present a screen that is based on the screen data received from controller30. Thus, the image of window83of the screen (FIG. 8) presented on display23is updated to draw the patch of the spot color selected by the user at the position designated by the user. In accordance with the user operation, controller30determines whether or not the position designation operation has been ended (step S10). When controller30does not determine that the operation has not been ended (NO in step S10), the process returns to step S6. A colorimetry position is designated for the next spot color. When controller30determines that the operation has been ended (YES in step S10), controller30generates configuration data334and stores configuration data334into HDD33(step S11). For each of the one or more spot colors selected by the user, configuration data334includes: the one or more colorimetry positions designated by the user on the job image of window83of the screen (FIG. 8); respective identifiers for the colorimetry positions; and target values76. The one or more colorimetry positions, the identifiers, and target values76are included in configuration data334in association with one another.

In the screen (FIG. 8), for example, three colorimetry positions are designated for a “custom spot color1” by the user. At the three colorimetry positions, respective identifiers A1, A2, A3for the colorimetry positions are drawn in the vicinity of the patches. Further, two colorimetry positions are designated for a “custom spot color2” by the user. At the two colorimetry positions, respective identifiers B1, B2for the colorimetry positions are drawn in the vicinity of the patches. For a “custom spot color3”, the user designates two colorimetry positions. At the colorimetry positions, identifiers C1, C2for the colorimetry positions are drawn in the vicinity of the patches. Here, each of the identifiers for the colorimetry positions for the spot colors is indicated using a combination of a symbol that identifies a corresponding spot color (symbol A, B, C, or the like) and a symbol that identifies a corresponding colorimetry position (numerical value 1, 2, 3, or the like). It should be noted that the expression of the identifier is not limited to this as long as the colorimetry position for the spot color can be identified.

In the colorimetry process, the user performs a user operation to perform the colorimetry process via a browser screen (FIGS. 9 and 13 to 15) presented by browser201. Here, HDD33of server300stores a plurality of pieces of configuration data334.

The following describes the colorimetry process in accordance with the flowchart ofFIG. 17. First, the user selects one piece of configuration data334from the plurality of pieces of configuration data334and inputs a colorimetry instruction. Controller30receives this user operation, and generates, based on configuration data334selected from the plurality of pieces of configuration data334of HDD33, screen data for a screen (FIG. 9) for preparing for the colorimetry. Controller30transmits the generated screen data to information processing apparatus200, and browser201causes display23to present the screen (FIG. 9) that is based on the received screen data (step S21).

The screen (FIG. 9) includes: a radio button91; a window92; a spot color list93; a guidance94having a message for supporting the preparation for colorimetry; a button95for instructing to start the colorimetry; and an identifier96for configuration data334. In spot color list93, data set in a below-described step S23is presented. Further, window92presents an image of colorimetry file335generated in a process of a below-described step S24. As the image of window92, there is presented an image of colorimetry file335that is based on configuration data334selected by the user, such as a thumbnail corresponding to the size of window92.

When the user operates a “target profile download” button of radio button91, browser201requests controller30for configuration data334selected by the user. Based on the request from browser201, controller30searches HDD33for configuration data334selected by the user, and transmits configuration data334to browser201.

Browser201sets, to spot color list93of the screen (FIG. 9), configuration data334received from server300(step S23). More specifically, the information set by the user in spot color list73of the target configuration creation screen (FIG. 7) is set to spot color list93.

A colorimetry file generation process (step S24) is performed. More specifically, in accordance with the user operation received via the browser screen, controller30generates colorimetry file335that is a printing file for causing printer140to perform printing, stores colorimetry file335into HDD33, and transmits colorimetry file335to browser201. Details of the colorimetry file generation process will be described later with reference toFIGS. 10 to 12 and 18.

In window92, browser201presents, as a thumbnail, an image that is based on colorimetry file335received from controller30(step S25). In the image that is based on colorimetry file335in window92, the patches of spot colors74designated by the user in spot color list93are placed at the colorimetry positions designated by the user (positions indicated by identifiers A1, A2, A3, B1, B2, C1, C2).

When the user operates a “wedge download” button of radio button91, downloading of colorimetry file335and printing in accordance with colorimetry file335are performed (step S26). More specifically, in accordance with the user operation on the “wedge download” button, browser201requests controller30for colorimetry file335corresponding to the image presented in window92. Based on the request from browser201, controller30searches HDD33for colorimetry file335, and downloads colorimetry file335to information processing apparatus200. Information processing apparatus200converts downloaded colorimetry file335into a print job and transmits the print job to image forming apparatus100. Image forming apparatus100executes the print job of colorimetry file335received from information processing apparatus200. Thus, printer140prints the image on sheet P in accordance with colorimetry file335, and outputs printed sheet P to tray271.

Controller30stands by until an operation for colorimetry instruction is received from the user (NO in step S27). When the colorimetry instruction is received from the user by operating button95(YES in step S27), browser201causes display23to present the colorimetry screen (FIG. 13) that is based on the screen data from controller30(step S28).

The colorimetry screen (FIG. 13) includes: a window130for presenting an image131of colorimetry file335in the form of, for example, a thumbnail; a guidance132including a message for colorimetry operation guidance to support the user; a colorimetry result133; and a button135to be operated to instruct start and end of the colorimetry.

In image131of colorimetry file335of window130, the patches (such as patches84,85) of the spot colors designated by the user are placed at the colorimetry positions designated by the user, and marks representing the identifiers for the colorimetry positions are drawn to correspond to the respective patches. More specifically, marks representing identifiers A1, A2, A3for the colorimetry positions are drawn in the vicinity of the patches of custom spot color1, marks representing identifiers B1, B2for the colorimetry positions are drawn in the vicinity of the patches of custom spot color2, and marks representing identifiers C1, C2for the colorimetry positions are drawn in the vicinity of the patches of custom spot color3. Each of these marks includes, for example, a letter/character.

The user operates colorimeter500to perform the colorimetry (steps S29to S31). More specifically, controller30determines whether or not start of the colorimetry has been instructed by the user operation on button135(step S29). The user performs the colorimetry onto the colorimetry positions (i.e., patches) on printed sheet P. Guidance132includes a message that instructs the user to perform the colorimetry onto the colorimetry positions in accordance with a predetermined order. For example, guidance132includes a message that instructs the user to perform the colorimetry onto the colorimetry positions in a predetermined order. For example, guidance132includes a message instructing the user to perform the colorimetry onto the colorimetry positions in the following order: the colorimetry positions of custom spot color1(order of identifiers A1→A2→A3)→the colorimetry positions of custom spot color2(order of identifiers B1→B2)→the colorimetry positions of custom spot color3(order of identifiers C1→C2). By checking the colorimetry positions indicated by the marks provided for the patches in image131of window130against the colorimetry positions indicated by the message, the user can specify the order of the colorimetry positions indicated by the message as the order of performing the colorimetry onto the patches printed on sheet P. Further, in order to readily specify the order of performing the colorimetry onto the patches on sheet P, the marks of the identifiers for the colorimetry positions may be printed on printing sheet P at positions that are consistent with the drawn positions of the marks of the identifiers in image131. More specifically, colorimetry file335may include a colorimetry file that allows a mark of an identifier for each colorimetry position to be printed on sheet P at a position associated with the colorimetry position (patch) (for example, in proximity to the patch).

By following such a guidance132, the user operates colorimeter500to perform the colorimetry onto sheet P at the positions corresponding to the designated positions of the spot colors. Colorimeter500outputs a colorimetry value for each colorimetry position.

It should be noted that when colorimeter500is included in image forming apparatus100, colorimeter500scans the identifier in the vicinity of each patch on sheet P (in proximity to the patch) using an OCR (optical character recognition) function. While colorimeter500specifies the colorimetry positions and colorimetry order indicated by the message of guidance132on sheet P based on the scanning result, colorimeter500performs the colorimetry onto the specified colorimetry positions in accordance with the specified order.

When controller30determines that button135has not been operated (NO in step S29), controller30repeats step S29. When it is determined that button135has been operated (YES in step S29), controller30receives colorimetry data indicating a colorimetry value via information processing apparatus200(step S30). The colorimetry data represents a result of colorimetry performed using colorimeter500by the user in accordance with guidance132, and represents, for example, a set in which the colorimetry values at the respective colorimetry positions indicated by identifiers A1, A2, A3, B1, B2, C1, C2are arranged in the order of the colorimetry positions.

Controller30determines whether or not end of the colorimetry has been instructed in accordance with the user operation on button135(step S31). When it is determined that end of the colorimetry has not been instructed (NO in step S31), the process returns to step S29and controller30determines whether or not button135has been operated to start colorimetry for the next spot color (step S29).

In step S30, in colorimetry result133of the colorimetry screen (FIG. 13), controller30presents an actual color (Actual) and a target color (Target) in association with a corresponding colorimetry position in such a manner that the actual color (Actual) can be compared with the target color (Target). The actual color (Actual) is based on the Lab value that is the colorimetry value. The target color (Target) is based on the Lab value of target value76at the colorimetry position. Colorimetry result133may be presented in real time in parallel with the colorimetry operation performed using colorimeter500by the user at each colorimetry position.

When controller30determines that end of the colorimetry has been instructed (YES in step S31), controller30performs a color verification process (step S32) using colorimetry result336. Details of the color verification process (step S32) will be described later. Further, controller30stores, into HDD33, color verification result337obtained through the color verification process. Controller30generates screen data for presenting color verification result337. Controller30transmits the generated screen data to information processing apparatus200, and browser201causes display23to present a screen (FIG. 14) that presents the colorimetry result that is based on the received screen data (step S33).

The screen (FIG. 14) has a mark144and a text box145in addition to the items shown in the screen (FIG. 9). Mark144represents a comprehensive verification result of the color verification result. Text box145is a text box for inputting an identifier of colorimetry job file340. Further, in the screen (FIG. 14), a spot color list93-1is presented instead of spot color list93inFIG. 9. In addition to the items included in spot color list93, spot color list93-1has an actual colorimetry value78at the colorimetry position for each spot color. Actual colorimetry value78indicates a representative value (for example, an average value, maximum value, minimum value, mode value, median value, or the like) of the actual colorimetry values at the one or more colorimetry positions for the corresponding spot color.

In the color verification process, for each spot color, it is determined whether or not a color difference exceeds the permissible range using target value76, colorimetry value78, and permissible range77. In the screen (FIG. 14), mark144indicates a color verification result that is based on a determination result for each spot color.FIG. 14shows a case where the color verification result represents “Failed” (Failure). For example, the case where mark144indicates “Failed” may include: a case where color verification results for one or more spot colors represent “Failed”; or a case where color verification results for all the spot colors represent “Failed”.

Returning to the colorimetry screen ofFIG. 13, controller30may present color verification result337as an image134in colorimetry result133of the screen (FIG. 13). Image134has bar-shaped pictograms corresponding to the colorimetry positions. The pictograms are presented, for example, in the following manner: a green pictogram1342is presented when a color verification result at a corresponding colorimetry position indicates “Passed”; and a red pictogram1341is presented when a color verification result at a corresponding colorimetry position indicates “Failed”. Although the manner of presenting a pictogram is switched in accordance with a color verification result, the switching of the manner of presenting a pictogram is not limited to the switching between colors.

It should be noted that the presentation of the color verification results at the colorimetry positions, i.e., the presentation of pictograms1341,1342may be performed in real time in parallel with the user operation of performing the colorimetry at the colorimetry positions using colorimeter500.

Controller30outputs a colorimetry report (step S34). More specifically, in order to check the colorimetry report, the user inputs the identifier of colorimetry job file340into text box145(FIG. 14). When controller30receives a request for the colorimetry report from browser201together with the identifier of colorimetry job file340received by the user operation in text box145, controller30searches HDD33for colorimetry job file340based on the identifier, generates screen data of a report screen (FIG. 15) based on searched colorimetry job file340, and transmits the screen data to browser201. Browser201causes display23to present a report screen (FIG. 15) that is based on the screen data of the report screen received from server300.

(c3. Presentation of Report Screen)

The report screen (FIG. 15) includes items51to57. Item55shows an image of job image data333representing the designated colorimetry positions (colorimetry positions indicated by identifiers A1, A2, A3, B1, B2, C1, C2). Item54indicates a target value, a colorimetry value, a color difference, a permissible range, and a color verification result (Passed or Failed) for each spot color designated by the user in association with a corresponding colorimetry position designated by the user. Item51indicates the same verification result as that of mark144of the comprehensive verification result. Items52and53indicate, for example, average and minimum values as representative values of color differences at all the colorimetry positions. In item54, the color verification results each indicating “Passed” may be presented by item57in the green color, and the color verification result indicating “Failed” may be presented by item56in the red color.

The following describes a process of generating the screen data of the report screen (FIG. 15) by controller30in accordance with the flowchart ofFIG. 20. Controller30creates base data of the report screen (step S71), places, as item54in the base data, a target value and a colorimetry value for each specific color in association with a corresponding colorimetry position (step S72), and places the image of job image data333as item55(step S73). From colorimetry result336, controller30obtains the colorimetry values obtained by colorimeter500at the colorimetry positions obtained from configuration data334(step S74). Controller30places the identifiers and patches for the colorimetry positions on the job image of item55for the sake of drawing (step S75). Thus, the report screen data is generated. Controller30transmits the generated screen data to information processing apparatus200, and browser201causes display23to present the report screen (FIG. 15) that is based on the received screen data.

On the screen of item55, report creation unit374may present the image that is based on image data333and may present a colorimetry value obtained at a position corresponding to each of one or more designated positions designated by the user operation on the image. Further, the colorimetry value may be presented in the form of a numerical value or the like, or may be presented in the form of a color patch indicating a coloration corresponding to the colorimetry value.

(c4. Process of Generating Colorimetry File335)

The following describes a process of generating colorimetry file335in accordance with the flowchart ofFIG. 18. Controller30obtains job image data333from HDD33by searching for job image data333(step S41), and obtains, from configuration data334, information of one or more spot colors designated by the user (step S42).

Controller30obtains one or more colorimetry positions for each spot color from configuration data334. The one or more colorimetry positions are designated by the user and each spot color is designated by the user. For the sake of drawing, controller30places the patches of the spot color on the image indicated by job image data333at the colorimetry positions designated by the user, the patches being based on patch data331(steps S43, S44, S45, S46, S47, S48). For example, the patches are placed for the sake of drawing such that the patches overlap with the original image indicated by job image data333(step S48). More specifically, controller30determines whether or not the patches of all the spot colors designated by the user have been completely placed at all the colorimetry positions designated by the user (step S43). When controller30determines that the patches have been completely placed at all colorimetry positions (YES in step S43), the process is ended. When the end is not determined (NO in step S43), controller30obtains a spot color based on the user operation (step S44), obtains colorimetry positions for the obtained spot color (step S45), and places the patches of the spot color at the colorimetry positions, repeatedly (steps S44to S48). Further, when it is not determined that patches of one spot color have been completely placed at the colorimetry positions (NO in step S46), the placement of the patches of the one spot color is repeated (steps S47, S48). However, when it is determined that the patches of the one spot color have been completely placed (YES in step S46), the process returns to step S43.

Each ofFIGS. 10 to 12illustrates colorimetry file335which is generated by controller30(i.e., CPU). When a print job that is based on colorimetry file335inFIG. 10is executed, colorimetry file335instructs printer140to print a patch (patch84,85, or the like) of each of the spot colors designated by the user on sheet P at a position corresponding to each of the colorimetry positions designated by the user, without printing the image of job image data333. When a print job that is based on colorimetry file335inFIG. 11is executed, colorimetry file335instructs printer140to print the image of job image data333and to print a patch (patch84,85, or the like) of each spot color designated by the user on sheet P at a position (i.e., a position on the image) corresponding to each of the colorimetry positions designated by the user. When a print job that is based on colorimetry file335inFIG. 12is executed, colorimetry file335instructs printer140to print an image of a standard wedge338on sheet P, and to print a patch (patch84,85, or the like) of each spot color designated by the user on sheet P at a position (i.e., position on the image of standard wedge338) corresponding to each of the colorimetry positions designated by the user. Standard wedge338is used for normal colorimetry.

Colorimetry file generation unit372can determine a position at which a patch of a predetermined color (for example, an image338representing the standard wedge) is to be printed, based on the position at which the patch of the spot color is to be printed. For example, colorimetry file generation unit372determines the position as a position at which the patch of the predetermined color is placed in proximity to the patch of the spot color. The position at which the patch of the predetermined color is placed in proximity to the patch of the spot color includes a position at which the patch of the spot color overlaps with (is overlaid on) the patch of the predetermined color. InFIG. 12, the image representing standard wedge338is shown as the color patch image of the predetermined color different from the spot color, but the color patch image of the predetermined color is not limited thereto.

It should be noted that colorimetry file generation unit372may have the following modes: a mode in which one of colorimetry files335shown inFIGS. 10 to 12is created; and a mode in which two or more of colorimetry files335are created in combination. For example, in the case of the mode in which the two or more of colorimetry files335are created in combination, in a scene of performing printing onto a plurality of sheets P in accordance with colorimetry files355that are based on the same image data333, colorimetry file355inFIG. 10can be applied to one sheet P, and colorimetry file355ofFIG. 11 or 12can be applied to another sheet P.

The following describes the color verification process in accordance with the flowchart ofFIG. 19. Referring toFIG. 19, controller30obtains colorimetry result336from HDD33by searching for colorimetry result336(step S51).

Controller30determines whether or not color verification calculation has been ended for all the spot colors indicated by colorimetry result336(step S53). When it is determined that the color verification calculation has been ended for all the spot colors (YES in step S53), the process is ended. On the other hand, when it is determined that the color verification calculation has not been ended for all the spot colors (NO in step S53), the process proceeds to step S54.

Controller30obtains information of one spot color from colorimetry result336, and obtains a target value for the one spot color from the obtained information (steps S54, S55). Controller30determines whether or not the color verification calculation has been performed for positions corresponding to the colorimetry positions of the one spot color (step S56). When it is determined that the color verification has not been ended for all the colorimetry positions of the one spot color (NO in step S56), controller30obtains a colorimetry value at each of the colorimetry positions of the spot color from colorimetry result336, calculates a color difference that is based on the colorimetry value and the target value for the one spot color, compares the calculated color difference with permissible range77corresponding to the one spot color, and determines whether or not the color difference exceeds permissible range77based on the result of comparison (steps S57, S59, S61).

When controller30determines that the color difference does not exceed permissible range77(NO in step S61), controller30determines the colorimetry value of the colorimetry position as “Passed” (Success) (step S62). When controller30determines that the color difference exceeds permissible range77(YES in step S61), controller30determines the colorimetry value of the colorimetry position as “Failed” (Failure) (step S63). Controller30stores the result of color verification (“Passed” or “Failed”) for each of the colorimetry positions of the spot color as color verification result337(step S64). Thereafter, the process returns to step S56.

When controller30determines that the color verification has been ended for all the designated colorimetry positions of one spot color selected in step S54(YES in step S56), controller30determines whether or not the color verification results of all the colorimetry positions of the one spot color indicate “Passed” (step S65). When controller30determines that the color verification results of all the colorimetry positions indicates “Passed” (Success) (YES in step S65), controller30determines the color verification of the one spot color as Success (step S66). Otherwise (NO in step S65), controller30determines the color verification of the one spot color as Failure (step S67). Controller30stores, into color verification result337, the result of step S66or S67obtained for the one spot color (step S68). Thereafter, the process returns to step S53.

Thus, when the image of colorimetry file335is printed on sheet P by printer140, color verification result337can indicate the color verification result of each spot color designated by the user on sheet P at the position corresponding to each of the colorimetry positions designated by the user.

The programs according to the flowcharts ofFIGS. 16 to 20, color verification program36, and the programs for implementing the functions of the respective units (screen generation unit375and color verification unit37) of controller30shown inFIG. 6are provided as programs executable by controller30or controller20of information processing apparatus200. Controller30or controller20serves as a computer including a hardware processor. Each of the programs can be also provided as a program product with the program being recorded in a computer-readable recording medium such as a storage unit (flexible disk, CD-ROM (Compact Disk-Read Only Memory)) attached to the computer of server300or information processing apparatus200such as recording media34-2,26-2, ROMs21,31, RAMs22,32, and a memory card. Alternatively, each of the programs may be provided with the program being recorded in a recording medium such as a hard disk included in a computer. Further, each of the programs can be also provided by downloading the program via networks400,600. Each of the programs can be executed by one or more hardware processors such as the CPUs included in controllers30,20, or by a combination of a hardware processor and a circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

It should be noted that each of the programs may be such that required program modules of program modules provided as parts of an OS (Operating System) of a computer are invoked in a predetermined sequence at a predetermined timing to cause the processor to perform a process. In this case, the program itself does not include the modules, and the process is performed in cooperation with the OS. Such a program that does not include the modules can be also included in the program of the embodiment.

The program according to the embodiment may be provided with the program being incorporated in part of another program. Also in this case, the program itself does not include modules included in the other program, and causes the processor to perform a process in cooperation with the other program. Such a program incorporated in the other program can be also included in the program according to each embodiment.

In another aspect, each of the programs described above can be provided to image forming apparatus100. In this case, each of the programs can be provided as a program product with the program being recorded in a computer-readable recording medium such as a storage unit (flexible disk, CD-ROM (Compact Disk-Read Only Memory)) attached to the computer of image forming apparatus100such as ROM, RAM, or memory card such as recording medium176. Alternatively, each of the programs may be provided with the program being recorded in a recording medium such as a hard disk included in a computer. Further, each of the programs can be also provided by downloading the program via networks400,600. Each of the programs can be executed by one or more hardware processors such as the CPU included in controller150, or by a combination of a hardware processor and a circuit such as an ASIC or FPGA.

A state of printer140is changed due to various factors such as deterioration of components with passage of time and environmental changes such as changes in ambient temperature or humidity. Also, characteristics of toner are also changed due to various factors. Hence, color reproducibility can be also varied due to these factors. On the other hand, in the printing industry, in the verification for color reproducibility, a spot color is a color having a special meaning for a user of a printed material because the spot color includes a logotype or a brand color that is a color representing a brand. Hence, there is a demand to frequently perform color verification in order to deal with the variation in color reproducibility.

In the present embodiment, with simple operations of interacting with controller30(more specifically, color verification unit37) via the browser screen, the user causes controller30to create configuration data334and colorimetry file335, causes printer140to execute a print job that is based on colorimetry file335, and causes controller30to perform color verification. Thus, the above demand can be responded to.

In order to perform the colorimetry for the color verification by the user operating colorimeter500using the printed image that is based on colorimetry file335and that is formed on sheet P, the support message is presented to the user to readily specify a position to be subjected to the colorimetry on sheet P in accordance with guidance132and the presented image of window130. Therefore, the user can readily specify a position to be subjected to the colorimetry on sheet P without requiring a special mechanism such as the one described in Japanese Laid-Open Patent Publication No. 2016-70697. Thus, the above demand can be responded to.