Image processing device, image forming system, image processing method and program

Abstract

To achieve color stabilization control according to a use case.SOLUTION: An image processing apparatus comprises: an operation receiving unit that receives an operation to select data indicating a target color in color stabilization control; a correction target determination unit that determines the selected target color as correction target data indicating the target color used for the color stabilization control; and a correction gamma generation unit that, based on the determined correction target data, generates correction gamma data used for gradation correction of image data for printing.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an image processing apparatus, an image forming system, an image processing method, and a program. [Background technology]

[0002] Technologies have been developed to correct the gradation of colors used in printing by image forming devices. For example, color stabilization processing is known, in which a printed material printed by the image forming device is read by a sensor and the read color is compared with a target color to correct the gradation of the image data to be printed.

[0003] For example, Patent Document 1 discloses a configuration for measuring the color of a printed matter and correcting the difference from a target color, in order to correct color fluctuations of the printed matter over time. Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology described in Patent Document 1, the target color aimed at during color stabilization control is defined as a "pre-stored output color," but the target color cannot be selected to suit the use case, and there is a problem in that color correction may be performed aiming for an output color different from the one the user wants to obtain.

[0005] The disclosed technology aims to realize color stability control tailored to the use case. [Means for solving the problem]

[0006] The disclosed technology includes an operation receiving unit that receives an operation to select data indicating a target color in color stability control, a correction target determination unit that determines the selected target color as the correction target data indicating the target color to be used in the color stability control, and a correction gamma generation unit that generates correction gamma data to be used for gradation correction of image data for printing based on the determined correction target data. When an operation mode based on a color based on test printing is set as the operation mode indicating the color reference, the operation accepting unit accepts selection of data indicating the target color in the color stability control from the test-printed print job data, and accepts an operation to select, as the operation mode indicating the color reference, one of an operation mode based on a color based on test printing, an operation mode based on a predetermined color, and an operation mode based on the color of an initial print in the same print job data. It is an image processing device. [Effects of the Invention]

[0007] It is possible to achieve color stability control tailored to the use case. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram illustrating an example of the overall configuration of an image forming system. [Figure 2] FIG. 1 illustrates an example of a hardware configuration of an image processing apparatus. [Figure 3] FIG. 2 illustrates an example of a hardware configuration of an image forming apparatus. [Figure 4] FIG. 1 is a first diagram illustrating an example of a functional configuration of an image processing apparatus. [Figure 5] FIG. 2 is a second diagram illustrating an example of the functional configuration of the image processing device. [Figure 6] FIG. 10 is a diagram illustrating an example of a flow of color stabilization processing. [Figure 7] FIG. 10 is a diagram for explaining the flow of proof printing. [Figure 8] FIG. 10 is a diagram showing an example of a color reference mode selection screen. [Figure 9] FIG. 10 is a diagram illustrating an example of print information. [Figure 10] FIG. 10 is a diagram illustrating an example of a proof standard setting screen. DETAILED DESCRIPTION OF THE INVENTION

[0009] (First embodiment) DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an image forming system according to the present invention will be described below with reference to the accompanying drawings.

[0010] FIG. 1 is a diagram showing an example of the overall configuration of an image forming system.

[0011] The image forming system 1 includes an image forming device 10, an image processing device 20, a user terminal 30, a management server 40, and a reading device 50. The image processing device 20, the user terminal 30, and the management server 40 are connected to each other via a communication network 60 so as to be able to communicate with each other.

[0012] The image forming device 10 is a device that forms an image, such as a color production printer, a laser printer, or an inkjet printer. The image forming device 10 receives image data from the image processing device 20 and prints an image on paper based on the received image data. The paper is an example of a transport medium on which an image is formed.

[0013] The image processing device 20 is a device, such as a DFE (Digital Front End), that processes image data formed by the image forming device 10. The image processing device 20 is connected to the image forming device 10 so as to be able to communicate with it.

[0014] When the image processing device 20 receives print job data along with a signal instructing the printing of an image from the user terminal 30 or the management server 40, it uses its built-in RIP (Raster Image Processor) engine to convert the data into image data in a format that can be processed by the image forming device 10, and sends the converted image data to the image forming device 10.

[0015] The user terminal 30 is a terminal that receives a user operation and instructs printing of an image. Specifically, the user terminal 30 transmits job data including image data to the image processing device 20 or the management server 40. In addition, in response to a user operation, the user terminal 30 transmits information indicating thresholds for color stabilization processing to the image processing device 20. Furthermore, the user terminal 30 may display a screen indicating the execution status of the color stabilization processing under display control by the image processing device 20.

[0016] When the management server 40 receives job data from the user terminal 30, it adds the job data to a queue in a storage unit that stores job data waiting to be printed. Then, the management server 40 extracts the job data from the queue in the order in which it was added to the queue or according to an appropriately set priority, and transmits the job data to the image processing device 20.

[0017] The reading device 50 is a device that reads an image from paper that has been printed by the image forming device 10. The reading device 50 is communicably connected to the image forming device 10. The reading device 50 transmits read image data indicating the read image to the image processing device 20 via the image forming device 10. The reading device 50 may read an image using a spectroscopic sensor, or may be any other device that can convert an original image into digital image data, such as an RGB scanner. The reading device 50 may also be configured to be included inside the image forming device 10, such as an inline sensor.

[0018] The communication network 60 is a LAN (Local Area Network) or the Internet, etc., and is a network that realizes data communication.

[0019] FIG. 2 is a diagram illustrating an example of a hardware configuration of the image processing apparatus.

[0020] The image processing device 20 is constructed by a computer and includes a CPU (Central Processing Unit) 201, a ROM (Read Only Memory) 202, a RAM (Random Access Memory) 203, an HDD (Hard Disk Drive) / SSD (Solid State Drive) 204, and an I / F (Interface) 205, all of which are interconnected by a bus.

[0021] The CPU 201 reads out a program stored in the ROM 202 or the HDD / SSD 204 and stores it in the RAM 203. The CPU 201 then executes various processes, which will be described later, in accordance with the program stored in the RAM 203.

[0022] The ROM 202 is a non-volatile auxiliary storage device that stores programs that define the basic operations of the image processing device 20, such as BIOS.

[0023] The RAM 203 is a volatile main storage device and is used as a working area for the CPU 201.

[0024] The HDD / SSD 204 is a large-capacity nonvolatile auxiliary storage device that stores received image data, various processing programs (described later), setting information, and the like.

[0025] The I / F 205 includes a LAN (Local Area Network) card or the like, and is a relay when the image processing apparatus 20 communicates with the image forming apparatus 10, the user terminal 30, or the management server 40.

[0026] FIG. 3 is a diagram illustrating an example of a hardware configuration of an image forming apparatus.

[0027] The image forming apparatus 10 includes a controller 1110 , a short-range communication circuit 1120 , an engine control unit 1130 , an operation panel 12 , and a network I / F 1150 .

[0028] Of these, the controller 1110 has a CPU (Central Processing Unit) 1101, which is the main part of the computer, a system memory (MEM-P) 1102, a north bridge (NB) 1103, a south bridge (SB) 1104, an ASIC (Application Specific Integrated Circuit) 1106, a local memory (MEM-C) 1107, which is a memory unit, an HDD (Hard Disk Drive) controller 1108, and an HD 1109, which is a memory unit.

[0029] The NB 1103 and the ASIC 1106 are connected by an AGP (Accelerated Graphics Port) bus 1121 .

[0030] Of these, the CPU 1101 is a control unit that performs overall control of the image forming apparatus 10. The NB 1103 is a bridge that connects the CPU 1101 with the MEM-P 1102, the SB 1104, and the AGP bus 1121, and includes a memory controller that controls reading and writing to the MEM-P 1102, a PCI (Peripheral Component Interconnect) master, and an AGP target.

[0031] The MEM-P 1102 includes a ROM (Read Only Memory) 1102a, which is memory for storing programs and data that realize the functions of the controller 1110, and a RAM (Random Access Memory) 1102b, which is used for expanding the programs and data, and as a drawing memory during memory printing. The programs stored in the RAM 1102b may be provided by being recorded in an installable or executable file format on a computer-readable recording medium such as a CD-ROM, CD-R, or DVD.

[0032] The SB 1104 is a bridge for connecting the NB 1103 with PCI devices and peripheral devices. The ASIC 1106 is an integrated circuit (IC) for image processing purposes that has hardware elements for image processing, and serves as a bridge for connecting the AGP bus 1121, PCI bus 1122, HDD controller 1108, and MEM-C 1107.

[0033] The ASIC 1106 includes a PCI target and AGP master, an arbiter (ARB) that forms the core of the ASIC 1106, a memory controller that controls the MEM-C 1107, a plurality of DMACs (Direct Memory Access Controllers) that perform image data rotation and the like using hardware logic, and a PCI unit that transfers data between the scanner unit 1131 and the printer unit 1132 via a PCI bus 1122. The ASIC 1106 may be connected via an interface such as a USB (Universal Serial Bus) interface or IEEE 1394 (Institute of Electrical and Electronics Engineers 1394).

[0034] The MEM-C 1107 is a local memory used as an image buffer for copying and a code buffer. The HD 1109 is a storage for storing image data, font data used during printing, forms, etc. The HD 1109 controls the reading and writing of data from and to the HD 1109 under the control of the CPU 1101.

[0035] The AGP bus 1121 is a bus interface for a graphics accelerator card proposed to speed up graphics processing. The AGP bus 1121 can speed up the graphics accelerator card by directly accessing the MEM-P 1102 with high throughput.

[0036] The short-range communication circuit 1120 also includes a short-range communication antenna 1120a. The short-range communication circuit 1120 is a communication circuit such as NFC or Bluetooth (registered trademark).

[0037] Furthermore, the engine control unit 1130 is made up of a scanner unit 1131 and a printer unit 1132. The operation panel 12 also includes a panel display unit 12a such as a touch panel that displays current setting values, selection screens, etc. and receives input from the operator, and operation keys 12b including a numeric keypad that receives setting values ​​for image formation conditions such as density setting conditions, and a start key that receives a copy start instruction.

[0038] The controller 1110 controls the entire image forming apparatus 10, for example, controlling drawing, communication, input from the operation panel 12, etc. The scanner unit 1131 reads an image formed on a transport medium such as paper and generates image data. The printer unit 1132 includes a transfer unit that transfers an image using color materials such as a toner image onto the transport medium such as paper, a fixing unit that fixes the image, a heating unit or a drying unit, etc., and forms an image on the paper. The scanner unit 1131 or the printer unit 1132 also performs image processing such as error diffusion and gamma conversion.

[0039] The network I / F 1150 is an interface for performing data communication using a communication network. The short-range communication circuit 1120 and the network I / F 1150 are electrically connected to the ASIC 1106 via a PCI bus 1122.

[0040] FIG. 4 is a first diagram illustrating an example of the functional configuration of the image processing device.

[0041] The image processing device 20 includes an image processing unit 21, a color stabilization processing unit 22, and a storage unit .

[0042] The image processing unit 21 performs RIP processing to convert the document image into image data that can be output by the image forming apparatus 10 .

[0043] The color stabilization processing unit 22 performs processing to stabilize color conversion in image processing by the image processing unit 21. Specifically, the color stabilization processing unit 22 updates the correction gamma data used for color conversion by the image processing unit 21 based on the difference between the target color and the color read from the read image data.

[0044] The storage unit 23 stores the correction gamma data used for color conversion by the image processing unit 21 .

[0045] FIG. 5 is a second diagram illustrating an example of the functional configuration of the image processing device.

[0046] The image processing unit 21 includes a color conversion processing unit 211, a gradation correction unit 212, and a halftone processing unit 213. The color conversion processing unit 211 converts the color space of the image data of the document included in the received job data into a profile specified by the user. For example, the color conversion processing unit 211 may convert the image data into image data in a CMYK color space that matches the characteristics of the engine, or may convert the image data into a grayscale image using luminance information.

[0047] The gradation correction unit 212 corrects the gradation values ​​of the image data of the original document converted by the color conversion processing unit 211 to any gradation value that has been set. Note that since a linear gamma is set as the default setting value, the gradation correction unit 212 corrects the image data. When the correction gamma data is updated in response to the correction result from the color stabilization processing unit 22, the color conversion processing unit 211 corrects the gradation values ​​of the image data based on the updated correction gamma data.

[0048] The halftone processing unit 213 performs tone conversion processing on 8-bit document image data, and generates binary image data that can be output by the engine.

[0049] The image processing unit 21 transmits the processed image data to the image forming apparatus 10. The image forming apparatus 10 forms an image on a sheet based on the received image data.

[0050] The color stabilization processing unit 22 includes a mode determination unit 221, a measurement coordinate determination unit 222, a measurement unit 223, a correction target generation unit 224, a correction target determination unit 225, a correction gamma generation unit 226, an operation reception unit 227, and a display information transmission unit 228.

[0051] The mode determination unit 221 determines the color reference mode selected by the user and notifies the correction target determination unit 225. The color reference mode is an operation mode that indicates how to determine a target color that serves as a reference when correcting a color, and is selected by the user from, for example, "proof reference," "fixed reference," and "initial reference."

[0052] "Proof reference" is an operating mode that uses the color based on a test print (proof print) as the reference. "Fixed reference" is an operating mode that uses a predetermined color as the reference. "Initial reference" is an operating mode that uses the color of the initial print (e.g., the first page) of the same print job data as the reference.

[0053] The measurement coordinate determination unit 222 determines the image position (measurement coordinate) of a location suitable for measurement based on the image data of the document and the characteristic information of the paper. The measurement coordinate determination unit 222 may determine multiple measurement coordinates, and in that case, generates list data that associates the multiple determined measurement coordinate positions with job information and page information.

[0054] The measurement unit 223 receives read image data from the reading device 50 and measures the color of the read image data based on the measurement coordinates determined by the measurement coordinate determination unit 222. The measurement unit 223 inputs color information indicating the measured color to the correction target generation unit 224 in order to generate correction target data. Furthermore, in the case of a color reference mode in which a correction target is not generated, the measurement unit 223 inputs the color information to the correction gamma generation unit 226.

[0055] The correction target generation unit 224 generates correction target data based on color information (RGB values, Lab values, etc.), and stores the generated correction target data in the storage unit 23 together with information indicating the job ID, printing time, number of prints, etc.

[0056] The correction target determination unit 225 acquires information indicating the color reference mode selected by the user from the mode determination unit 221, and determines correction target data indicating the target color to be used in color stability control based on the job information.

[0057] The correction gamma generation unit 226 detects the difference between the determined correction target data and the color information (RGB values, Lab values, etc.) of the page to be processed, and generates correction gamma data for correcting the image data of the original. Then, the correction gamma generation unit 226 sets the generated correction gamma data in the gradation correction unit 212. The set correction gamma data is used to print the next page to be processed.

[0058] The operation accepting unit 227 accepts a selection operation of the color reference mode by the user via the user terminal 30. Furthermore, when the color reference mode is "proof reference," the operation accepting unit 227 accepts an operation of setting the proof reference by the user. The proof reference is correction target data used as a reference.

[0059] The display information sending unit 228 sends display information for displaying the control results (job name, print time, number of prints, etc.) when printing is completed to the user terminal 30. The user terminal 30 displays the received display information.

[0060] Next, the operation of the image processing device 20 will be described.

[0061] When printing is performed with the color stabilization function set to ON, job information, information about the paper used for printing, and image data of the original are input to the color stabilization processing unit 22. Then, the color stabilization processing unit 22 executes color stabilization processing.

[0062] FIG. 6 is a diagram showing an example of the flow of color stabilization processing.

[0063] The measurement coordinate determination unit 222 determines measurement coordinates (step S101). Specifically, it is desirable that the measurement positions are positions where the gradation changes gradually and can be measured evenly from the printing surface. Therefore, the measurement coordinate determination unit 222, for example, extracts pixel values ​​of a size that can be measured colorimetrically from the image data and calculates flatness. The measurement coordinate determination unit 222 may calculate flatness using a low-pass filter, Fourier transform, or the like. For example, a position of the size that can be measured colorimetrically, where the gap between the maximum pixel value and the minimum pixel value is small, may be determined as a colorimetric position where flatness is superior. Furthermore, the measurement coordinate determination unit 222 may determine the measurement positions using a technique such as clustering, so as to prevent bias in the measurement positions.

[0064] Next, the measurement unit 223 acquires the read image data from the reading device 50 (step S102), and measures the color at the measurement coordinates of the read image data (step S103).

[0065] Next, the mode determination unit 221 determines the color reference mode selected by the user and notifies the correction target determination unit 225 (step S104). If the mode determination unit 221 determines that the color reference mode is "proof reference" (step S104: proof reference), the correction target generation unit 224 determines whether the proof reference has been set (step S105).

[0066] If the correction target generation unit 224 determines that the proof standard has not been set (step S105: No), it generates correction target data (step S106) and stores it in the storage unit 23 (step S107). Specifically, the correction target generation unit 224 generates correction target data expressed as gamma values ​​by decomposing Lab values ​​or RGB values ​​into CMYK. The correction target generation unit 224 may use, for example, an LUT for decomposing colors from Lab values ​​into CMYK.

[0067] Then, the display information transmitting unit 228 transmits the print information to the user terminal 30 (step S108).

[0068] Furthermore, in step S104, if the mode determination unit 221 determines that the color reference mode is "fixed reference" (step S104: fixed reference), the correction target determination unit 225 determines correction target data (step S109). Also, in step S105, if the correction target generation unit 224 determines that the proof reference has been set (step S105: Yes), the process proceeds to step S109.

[0069] Then, the correction gamma generation unit 226 generates the correction gamma data (step S110), and the display information transmission unit 228 transmits the print information to the user terminal 30 (step S108).

[0070] Furthermore, in step S111, if the mode determination unit 221 determines that the color reference mode is "initial reference" (step S104: initial reference), correction target data is generated (step S111). Then, the correction target determination unit 225 determines the correction target data (step S109).

[0071] Next, the printing flow when the color reference mode is "proof reference" will be described.

[0072] FIG. 7 is a diagram for explaining the flow of proof printing.

[0073] The operation acceptance unit 227 accepts a selection operation of a color reference mode by a user via the user terminal 30 (step S201). Here, the user selects "proof reference." Next, the operation acceptance unit 227 accepts print job settings via the user terminal 30 (step S202). For example, print job settings include paper settings or color profile settings. At this time, a job ID, which is an identification number for each print job data, is assigned.

[0074] The image forming apparatus 10 then prints the image on paper (step S203). This printing functions as proof printing (trial printing). The user checks whether the printout is as expected. For example, the user checks the imposition settings, print position, color, etc. Regarding color, adjustments can be made using methods such as gamma adjustment if the user has received color specifications from a customer or other source using a color patch or color proof, or if the color appears dull and gives a bad impression. Fine adjustments can also be made repeatedly through trial and error based on the current engine state.

[0075] In step S203, the image forming apparatus 10 may print using a proof printing function or a normal printing function. The proof printing function is a function that always prints only one copy regardless of the number of copies specified on the print job setting screen. The normal printing function is a function that prints the number of copies specified by the user. When using the normal printing function, the user simply specifies the number of copies as one on the screen for setting the print job.

[0076] 6 after printing by the image forming apparatus 10 in step S203. In this case, the image processing apparatus 20 proceeds to the processing of step S105 because the color reference mode is set to "proof reference" in step S104. Then, because the proof reference is not set in the processing of step S105, the processing proceeds to the processing of step S106, where the correction target generation unit 224 generates correction target data.

[0077] The image forming apparatus 10 may repeatedly execute the process of step S203 until the user determines that the color is the desired color. Then, the operation accepting unit 227 of the image processing apparatus 20 accepts the setting of the proof standard on the proof standard setting screen on which the printing information is displayed (step S204). A specific example of the proof standard setting screen will be described later.

[0078] Then, the image forming apparatus 10 prints an image on paper (step S205). This printing functions as production printing. In the processing of step S205 as well, the image processing apparatus 20 executes the color stabilization processing shown in FIG. 6 after printing in the image forming apparatus 10. In this case, the image processing apparatus 20 proceeds to processing of step S105 because the color reference mode is set to "proof reference" in step S104. Then, in the processing of step S105, because the proof reference is set, the processing proceeds to processing of step S109, where the correction target determination unit 225 determines correction target data.

[0079] Next, the screens and the like displayed on the user terminal 30 will be described.

[0080] 8 is a diagram showing an example of a color reference mode selection screen. The color reference mode selection screen accepts selection of one of "proof reference", "fixed reference", and "initial reference" as the color reference mode.

[0081] As use cases for each mode, for example, a user may select "Fixed Reference" if they want to reproduce the same color across multiple print jobs. Alternatively, a user may select "Initial Reference" if they want to reproduce the same color within a single job. Furthermore, a user may select "Proof Reference" if they want to reproduce the color of a completed proof print.

[0082] The user selects the most appropriate mode depending on the use case. Note that the color reference modes are not limited to the above three types, and other options may be available. For example, there may be a color reference mode that allows the user to directly generate and set gamma data with optimal color characteristics. Furthermore, a configuration may be possible in which switching of the color reference mode can be set for each job.

[0083] FIG. 9 is a diagram illustrating an example of the print information.

[0084] The printing information stored in the storage unit 23 includes, for example, items such as "job ID", "job name", "print time", "number of prints", "reference data", and "reference selection".

[0085] The value of the item "Job ID" is an identifier for identifying each print job data. The value of the item "Job Name" is the name in the storage unit 23 of each print job data.

[0086] The value of the item "Printing time" is the time when each print job data was actually printed. The value of the item "Number of times printed" is the number of times each print job data was printed.

[0087] The value of the item "Reference Data" is the correction target data used for tone correction for each print job data. The value of the item "Reference Selection" is a flag value that indicates whether or not the data has been set as the proof reference by the user. For example, "1" is a value that indicates that the data has been set as the proof reference.

[0088] In step S109 of the color stabilization processing shown in FIG. 6, the correction target determination unit 225 determines that the correction target data to be used is the correction target data indicated in the item "Reference Data" in the entry where the value of the item "Reference Selection" is "1."

[0089] FIG. 10 is a diagram showing an example of the proof standard setting screen.

[0090] When the user terminal 30 receives print information from the image processing device 20 in step S108 of the color stabilization process shown in FIG. 6, it displays a proof standard setting screen including the print information. The proof standard setting screen allows the user to view the print information and select the print job data to be set as the proof standard. Note that the proof standard setting screen may also be configured to allow the user to select the print job data to be used as the proof standard for each print run, assuming that the same print job data is printed multiple times. This allows the user to select which print run is suitable as the proof standard.

[0091] Each time the same job is printed, the print count is incremented. The print count may also be included in the job name. In other words, even if the same print job data is printed, a different job name may be assigned each time it is printed.

[0092] According to the image forming system 1 of this embodiment, the gradation correction process is performed using correction target data based on the color set by the user as the proof standard. Therefore, the correction target when performing color stability control can be switched to suit the user's use case, thereby realizing color stability control suited to the use case.

[0093] (Second embodiment) A second embodiment will be described below. In the second embodiment, a form in which "fixed reference" is selected as the color reference mode will be described. Therefore, in the following description of the second embodiment, differences from the first embodiment will be mainly described, and components having the same functional configuration as those in the first embodiment will be assigned the same reference numerals as those used in the description of the first embodiment, and descriptions of those components will be omitted.

[0094] In this embodiment, the printing flow when the color reference mode is "fixed reference" will be described.

[0095] 7, the operation accepting unit 227 accepts a selection operation of a color reference mode by a user via the user terminal 30 (step S201). Here, the user selects "fixed reference".

[0096] In this case, steps S203 and S204 shown in Fig. 7 are skipped. Then, the image forming apparatus 10 prints an image on paper (step S205). The image processing apparatus 20 executes the color stabilization process shown in Fig. 6 after printing in the image forming apparatus 10. In this case, since the color reference mode is set to "fixed reference" in step S104, the image processing apparatus 20 proceeds to the process of step S109, and the correction target determination unit 225 determines the correction target data stored in advance in the storage unit 23.

[0097] According to the image forming system 1 of this embodiment, the tone correction process is performed using correction target data based on a color set as a fixed reference by the user, thereby enabling the same color to be reproduced across multiple print jobs.

[0098] (Third embodiment) A third embodiment will be described below. In the third embodiment, a mode in which "initial reference" is selected as the color reference mode will be described. Therefore, in the following description of the third embodiment, differences from the first embodiment will be mainly described, and components having the same functional configuration as those in the first embodiment will be assigned the same reference numerals as those used in the description of the first embodiment, and descriptions thereof will be omitted.

[0099] In this embodiment, the printing flow when the color reference mode is "initial reference" will be described.

[0100] 7, the operation accepting unit 227 accepts a selection operation of a color reference mode by a user via the user terminal 30 (step S201). Here, the user selects "initial reference."

[0101] In this case, steps S203 and S204 shown in Fig. 7 are skipped. Then, the image forming apparatus 10 prints an image on paper (step S205). The image processing apparatus 20 executes the color stabilization process shown in Fig. 6 after printing in the image forming apparatus 10. In this case, since the color reference mode is set to "initial reference" in step S104, the image processing apparatus 20 proceeds to the process of step S111, and the correction target generation unit 224 generates correction target data based on, for example, information on the first page of the print job.

[0102] Here, the correction target generation unit 224 may generate correction target data based on information obtained by averaging multiple pages at the beginning of a print job in order to reduce unevenness, etc. The correction target generation unit 224 stores the generated correction target data in the storage unit 23.

[0103] Then, in printing the subsequent pages, the correction target determination unit 225 determines the correction target data stored in the storage unit 23 as the correction target data to be used.

[0104] According to the image forming system 1 of this embodiment, the gradation correction process is performed using correction target data based on the color set as the initial reference by the user, so that the same color can be reproduced within one print job.

[0105] In each of the above-described embodiments, the image forming apparatus 10 and the image processing apparatus 20 can be configured to share the disclosed processing steps in various combinations. Furthermore, the elements of the image forming apparatus 10 and the image processing apparatus 20 may be integrated into a single device or may be separated into multiple devices.

[0106] In some embodiments, some functions of the image processing device 20 may be implemented by an information processing device. The information processing device may be configured as an information processing system including multiple computing devices, such as a server cluster. The multiple computing devices may be configured to communicate with each other via any type of communication link, including a network, shared memory, etc., and may perform the processes disclosed herein.

[0107] Each function of the above-described embodiments can be realized by one or more processing circuits. Here, the term "processing circuit" in this specification includes a processor programmed to perform each function by software, such as a processor implemented by an electronic circuit, as well as devices such as an ASIC (Application Specific Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), and conventional circuit modules designed to perform each of the above-described functions.

[0108] Although the present invention has been described above based on the embodiments, the present invention is not limited to the requirements shown in the above embodiments. These requirements can be changed without departing from the spirit of the present invention, and can be appropriately determined depending on the application form. [Explanation of symbols]

[0109] 1. Image forming system 10 Image forming device 20 Image processing device 21 Image processing section 22 Color stabilization processing section 23 Memory section 30 User terminals 40 Management Server 50 Reading device 60 Communication Network 211 Color conversion processing unit 212 Gradation Correction Section 213 Halftone Processing Unit 221 Mode determination unit 222 Measurement coordinate determination unit 223 Measuring section 224 Correction target generation unit 225 Correction target determination unit 226 Correction gamma generator 227 Operation reception section 228 Display information transmission unit [Prior art documents] [Patent documents]

[0110] [Patent Document 1] Patent No. 5618211

Claims

1. an operation receiving unit that receives an operation to select data indicating a target color in color stability control; a correction target determination unit that determines the selected aim color as correction target data that indicates the aim color to be used in the color stability control; a correction gamma generation unit that generates correction gamma data used for tone correction of image data for printing based on the determined correction target data, the operation receiving unit receives a selection of data indicating the target color in the color stability control from the print job data of the test print when an operation mode based on a color based on test print is set as an operation mode indicating a color reference; accepts an operation to select, as an operation mode indicating a color reference, one of an operation mode based on a color based on a test print, an operation mode based on a predetermined color, and an operation mode based on a color of an initial print in the same print job data; Image processing device.

2. the operation accepting unit accepts selection of data indicating the target color in the color stability control for each print run from the print job data that has been test printed; The image processing device according to claim 1 .

3. When an operation mode based on a color based on a test print is set as an operation mode indicating a color reference and when selection of data indicating the target color is not accepted, the apparatus further includes a correction target generation unit that generates correction target data based on color information measured from the read image data and stores the generated correction target data in a storage unit together with print information.

3. The image processing device according to claim 1.

4. An operation receiving unit that receives an operation to select data indicating a target color in color stability control; a correction target determination unit that determines the selected aim color as correction target data that indicates the aim color to be used in the color stability control; a correction gamma generation unit that generates correction gamma data used for tone correction of image data for printing based on the determined correction target data; a correction target generating unit that generates correction target data based on color information measured from the read image data and stores the generated correction target data in a storage unit together with print information when an operation mode based on a color based on a test print is set as an operation mode indicating a color reference and when selection of data indicating the target color is not accepted; a display information sending unit that sends display information including the print information and the correction target data generated based on color information measured from the read image data to a user terminal when an operation mode based on a color based on a test print is set as an operation mode indicating a color reference and selection of data indicating the target color is not accepted, the operation accepting unit accepts selection of data indicating the target color in the color stability control from the print job data of the test print when an operation mode based on a color based on test print is set as the operation mode indicating the color reference; Image processing device.

5. An image forming system including an image forming apparatus and an image processing apparatus, The image processing device includes: an operation receiving unit that receives an operation to select data indicating a target color in color stability control; a correction target determination unit that determines the selected aim color as correction target data that indicates the aim color to be used in the color stability control; a correction gamma generation unit that generates correction gamma data used for tone correction of image data for printing based on the determined correction target data; a gradation correction unit that corrects the gradation of the image data based on the corrected gamma data, the operation receiving unit receives a selection of data indicating the target color in the color stability control from the print job data of the test print when an operation mode based on a color based on test print is set as an operation mode indicating a color reference; accepts an operation to select an operation mode indicating a color reference from an operation mode based on a color based on a test print, an operation mode based on a predetermined color, and an operation mode based on a color of an initial print in the same print job data; the image forming device forms an image on a conveying medium based on the image data whose gradation has been corrected. Imaging system.

6. 1. A computer-implemented method comprising: receiving an operation to select data indicating a target color in color stability control; determining the selected aim color as correction target data indicating the aim color to be used in the color stability control; generating correction gamma data to be used for gradation correction of image data for printing based on the determined correction target data; In the step of accepting the operation, when an operation mode based on a color based on a test print is set as an operation mode indicating a color reference, a selection of data indicating the target color in the color stability control is accepted from test print job data; accepts an operation to select, as an operation mode indicating a color reference, one of an operation mode based on a color based on a test print, an operation mode based on a predetermined color, and an operation mode based on a color of an initial print in the same print job data; Image processing methods.

7. On the computer, receiving an operation to select data indicating a target color in color stability control; determining the selected aim color as correction target data indicating the aim color to be used in the color stability control; generating correction gamma data to be used for gradation correction of image data for printing based on the determined correction target data; A program for executing In the step of accepting the operation, when an operation mode based on a color based on a test print is set as an operation mode indicating a color reference, a selection of data indicating the target color in the color stability control is accepted from test print job data; accepts an operation to select, as an operation mode indicating a color reference, one of an operation mode based on a color based on a test print, an operation mode based on a predetermined color, and an operation mode based on a color of an initial print in the same print job data; program.

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