Image forming apparatus, image forming method, and program

Abstract

To solve the problem in which: when an adjustment chart is inserted and printed in the middle of a print job, constantly printing a four-color adjustment chart creates a color adjustment chart even when pages of the print job are composed of black-and-white images, which causes unnecessary consumption of toner and wear of a device member.SOLUTION: An image forming apparatus acquires an image forming mode when a predetermined number of sheets are printed, and determines a gradation pattern image according to the acquired image forming mode. When acquiring a color image forming mode, the image forming apparatus forms a color gradation pattern image, and when acquiring a black-and-white image forming mode, forms a black-and-white gradation pattern image.SELECTED DRAWING: Figure 14

Description

[Technical field]

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

[0002] Image forming devices are known that have a configuration having multiple printing modes that can switch between image forming means for color printing and black-and-white printing. For example, when a certain number of black-and-white image pages are printed in succession, the forming means of the image forming device is switched to a black-and-white image forming mode that can print only with black toner. Control of components such as toner other than black and the photosensitive drum is temporarily suspended. By switching the printing mode, it is expected that productivity can be improved while mechanical deterioration can be suppressed. However, switching the printing mode takes a long time because the forming means is changed.

[0003] Also known is a printing system in which an in-line sensor is connected to the rear stage of an image forming apparatus that forms an image on paper, and the image formed on the paper by the image forming apparatus is read by the in-line sensor.

[0004] In such a printing system, an in-line sensor reads density adjustment patches printed on paper by an image forming device, and adjustment results can be fed back to the printing device in real time even during printing of a job with a large number of pages. It is desirable to print the patches in the margins of the output (paper), but depending on the type and size of the paper, it may not be possible to print the adjustment patches.

[0005] Patent Document 1 discloses a technique for generating an adjustment chart by printing patches on paper different from the output of a print job, and inserting and printing the adjustment chart when a predetermined number of print pages is reached during printing of the job. Patent Document 1 also discloses a technique for reading the density of the patches on the printed adjustment chart and feeding it back to the device to adjust the density. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2010-122377 A Summary of the Invention [Problem to be solved by the invention]

[0007] In Patent Document 1, regardless of the print mode when the adjustment chart is inserted, an adjustment chart consisting of four colors, cyan, magenta, yellow, and black, is always printed, and the tone correction table for each of the four colors is updated. In the black-and-white image formation mode, only black toner is required for printing, so the updated tone correction table uses only black. Even if the tone correction table is updated, other toners are not used until the next color image page is printed. Therefore, always forming images of patches for all colors and reading and performing tone correction results in unnecessary use of chromatic toners. [Means for solving the problem]

[0008] In order to solve the above problem, an image forming apparatus according to one aspect of the present invention has the following configuration: That is, in an image forming apparatus capable of switching between a color image forming mode in which printing is performed using a plurality of recording materials including chromatic recording materials, and a black-and-white image forming mode in which printing is performed using a monochrome recording material without using chromatic recording materials, the image forming apparatus includes a printing means for printing an image, an enabling means for enabling an interrupt adjustment setting, a means for not incrementing an adjustment counter each time one page is printed when the setting is not enabled, and a means for incrementing the adjustment counter each time one page is printed when the setting is enabled, and a means for incrementing the adjustment counter each time one page is printed when the adjustment counter reaches a predetermined value, the image forming apparatus includes: a printing means for printing an image; Floor a control means for printing a key pattern image; The aboveThe image forming apparatus includes a color measurement means for reading and measuring a gradation pattern image, a generation means for generating gradation correction data based on the color measurement result of the gradation pattern image by the color measurement means and a reference value, and a correction means for performing gradation correction on image data using the gradation correction data generated by the generation means, and is characterized in that the image forming mode of the image forming device when the adjustment counter reaches the predetermined value is obtained, and if the obtained image forming mode is a color image forming mode, a color gradation pattern image including a plurality of patch images having gradually differing densities is printed using the chromatic color recording material, and if the obtained image forming mode is a black-and-white image forming mode, a black-and-white gradation pattern image is printed using the black monochrome recording material without using the chromatic color recording material. Effect of the Invention

[0010] According to the present invention, The adjustment counter can be incremented on the condition that the interrupt adjustment setting is enabled, and when the interrupt adjustment setting is not enabled, the adjustment counter can be prevented from incrementing. When the adjustment counter reaches a specified value, Since the color composition of the gradation pattern image can be changed according to the image formation mode of the device when the gradation pattern image is printed, excessive consumption of the recording material used for printing the gradation pattern image can be prevented. Can do. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 illustrates an example of the configuration of a printing system. [Diagram 2] A diagram illustrating the internal configuration of a printing system. [Diagram 3] A block diagram showing an example of the software configuration of a printing system. [Figure 4] FIG. 1 is a flow chart showing an execution flow of an image processing apparatus. [Diagram 5] FIG. 1 is a flow chart showing an execution flow of print control in an image forming apparatus. [Figure 6] FIG. 1 is a flow chart showing an execution flow of interrupt adjustment in an image forming apparatus. [Figure 7] FIG. 1 is a flow chart showing an execution flow of page image generation of an adjustment chart in an image forming apparatus. [Figure 8]FIG. 13 is a diagram showing an example of a screen for setting an interrupt adjustment interval. [Figure 9] FIG. 13 is a diagram showing an example of a print management application screen. [Figure 10] FIG. 13 is a diagram showing an example of a print job setting screen. [Figure 11] FIG. 13 is a diagram showing an example of a print job setting screen. [Figure 12] FIG. 13 is a diagram showing an example of the layout of an adjustment chart. [Figure 13] FIG. 4A is a diagram showing an example of measurement value data, FIG. 4B is a diagram showing an example of reference value data, and FIG. 4C is a diagram showing an example of correction values. [Figure 14] FIG. 13 is a flow chart showing an execution flow of page image generation of an adjustment chart according to a third embodiment. [Figure 15] FIG. 13 is a block diagram showing an example of the software configuration of a printing system according to a third embodiment. [Figure 16] FIG. 11 is a flow chart showing an execution flow chart of an image processing apparatus according to a third embodiment. [Figure 17] FIG. 11 is a flow chart showing an execution flow of print control in an image forming apparatus according to a third embodiment. [Figure 18] Block diagram showing an example of a hardware configuration [Figure 19] FIG. 1 is a flow chart showing an execution flow of interrupt adjustment in an image forming apparatus. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0013] <Printing system configuration> Fig. 1 is a diagram showing an example of the configuration of a printing system according to the present embodiment. As shown in Fig. 1, in the printing system, an image processing device 20 connected to an image forming device 10 and a client PC 30 are connected via a network 40 such as a LAN. The image forming device 10 and the image processing device 20 have a function (printing function) of forming an image on a recording medium such as paper or a plastic sheet (hereinafter referred to as "paper") in accordance with a print request received from the client PC 30.

[0014] The configuration of the printing system is not limited to that shown in Fig. 1, and it is sufficient that at least one or more client PCs 30, image forming apparatus 10, and image processing apparatus 20 are communicably connected via network 40. Image processing apparatus 20 may be configured as a print server independent of image forming apparatus 10 as shown in the figure, or may be an integrated system in which image forming apparatus 10 has the same functions internally. Furthermore, network 40 may be wired or wireless.

[0015] <Printing system hardware configuration> FIG. 18 is a block diagram showing the hardware configuration of a printing system according to this embodiment. In the image forming apparatus 10, the device controller 100 is a controller that controls the devices of the image forming apparatus 10. The CPU 111 generally controls access to various devices connected to a system bus 116 based on a control program stored in the ROM 112 or a hard disk drive (HDD) 114. The ROM 112 stores control programs executable by the CPU 111. The RAM 113 mainly functions as a main memory, a work area, etc. for the CPU 111, and is configured so that the memory capacity can be expanded by an optional RAM connected to an expansion port (not shown). The hard disk drive (HDD) 114 stores a boot program, various applications, font data, user files, edit files, etc. In this embodiment, the HDD 114 is used, but an SD card, a flash memory, etc. may be used as an external storage device other than the HDD 114. The control system I / F 115 transmits and receives information required for print control to the image processing apparatus 20. The printer I / F 117 controls image output to the print device 200. The operation unit I / F 119 controls the display of the display unit 132 of the operation unit 130 and controls the input of various setting information set by the input unit 131. The image data system I / F 120 receives image data to be sent to the printing device 200 from the image processing device 20. The sensor I / F 118 transmits operation instructions to a sensor 220 provided inside the printing device 200 and receives measurement results of the sensor 220. The sensor 220 is disposed between a fixing unit and a paper discharge outlet on a paper transport path of the printing device 200. Alternatively, the sensor 220 may be disposed on a paper transport path of a finishing device (not shown) connected to a downstream stage of the printing device 200. A measurement chart with color patches arranged according to the arrangement position of the sensor is printed, and the chart passes through the sensor 220, whereby the sensor 220 measures information of the patches, such as spectral values, chromaticity values, and density. The measured information is used for the adjustment functions of both devices.

[0016] In the image processing device 20, the RIP controller 140 performs processing required for executing the print processing in the image processing device 20, such as analyzing the input print job and expanding the print job into image data. The CPU 141 generally controls access to various devices connected to a system bus 146 based on a control program stored in the ROM 142 or a hard disk drive (HDD) 144. The ROM 142 stores control programs executable by the CPU 141. The RAM 143 mainly functions as the main memory, work area, etc. of the CPU 141, and is configured so that the memory capacity can be expanded by an optional RAM connected to an expansion port (not shown). The hard disk drive (HDD) 144 stores a boot program, various applications, font data, user files, edit files, etc. In this embodiment, the HDD 144 is used, but in addition to the HDD 144, an SD card, a flash memory, etc. may be used as an external storage device. The control system I / F 145 transmits and receives information required for print control to and from the image forming device 10. The image data system I / F 147 transmits image data to be output by the printing device 200 to the image forming apparatus 10. The operation unit I / F 148 controls the display of a display unit 152 provided in the operation unit 150 and controls the input of various setting information set by an input unit 151. The network I / F 149 performs data communication with an external network 40 via a network cable.

[0017] The image processing apparatus 20 may also have a function of submitting the same print job as the client PC 30 described later. A print job is submitted from the operation unit 150 to the RIP controller 140 via a printer driver or a print management application.

[0018] The client PC 30 is connected to the image processing device 20 through an external network 40. The client PC 30 submits a print job to the image processing device 20 via a printer driver or a print management application.

[0019] <Internal structure of the printing system> FIG. 2 is a diagram for explaining the internal structure of an electrophotographic printing device 200 mounted on the image forming apparatus 10 according to this embodiment, and the relationship between the respective devices.

[0020] In Fig. 2, the area enclosed by a dashed line indicates the printing device 200. The printing device 200 has four stations corresponding to the toners (recording materials) of cyan (C), magenta (M), yellow (Y), and black (K). These four stations, arranged in the horizontal direction, sequentially form toner images in the order of yellow, magenta, cyan, and black. Note that yellow toner, magenta toner, and cyan toner are chromatic recording materials.

[0021] Each station is provided with a photosensitive drum 201 as an image carrier. On the circumferential surface of the photosensitive drum 201, a charger 202, an exposure device 203, a developing device 204, a cleaning device 207, and a pre-exposure device 208 are arranged. The developing device 204 is arranged with a developing roller 205 that supplies a developer (toner) to the photosensitive drum 201. In the intermediate transfer unit 206, an intermediate transfer belt 209 and a primary transfer roller 210 are in contact with the photosensitive drum 201 at each station via the intermediate transfer belt 209 in a manner opposing each other. Furthermore, a secondary transfer inner roller 211 and a secondary transfer roller 212 are also in contact with each other via the intermediate transfer belt 209, and are arranged in such a configuration that the intermediate transfer belt rotates in the conveying direction. The fixing device 213 is composed of a heating film (heating rotatable body) 214, a fixing roller 215, and a pressure roller 216, and fixes the toner transferred to the paper 222 by heating and pressurizing it. A paper discharge roller 217 discharges the paper 222 that has passed through the fixing device 213 onto a paper discharge tray 218 .

[0022] A colorimetric sensor 220 is installed between the fixing device 213 and the paper discharge roller 217 so as to be able to read the printed surface, measures the density of a patch formed on the paper 222 after fixing, and notifies the controller 100 of the colorimetric data (density data). A cleaning blade 221 cleans toner remaining on the intermediate transfer belt 209 without being transferred to the paper 222 during the secondary transfer. A paper feed roller 224 feeds the paper 222 stored in a paper feed cassette 223 (paper feed stage). Note that although there is one paper feed cassette 223 in FIG. 2, the printing device 10 is equipped with multiple paper feed cassettes 223 corresponding to various paper sizes and types.

[0023] Next, the software configuration of each device according to this embodiment will be described.

[0024] <Software configuration of image forming device> 3A is a block diagram of a device controller 100 which is a software module configuration of the image forming apparatus 10. These software modules are stored as programs in the HDD 114, and are read by the CPU 111 into the RAM 113 and executed.

[0025] The UI control unit 301 controls display of the display unit 132 in the operation unit 130 via the operation unit I / F 119 , and controls input of various setting information set in the input unit 131 .

[0026] The page image analysis unit 302 analyzes the print job received from the image processing device 20. In this embodiment, it is determined whether the interrupt adjustment setting of the print job is enabled. The page image control unit 303 executes the print processing required by the image forming device 10 for the print job. It performs density gradation correction processing, halftone processing, etc., and generates data that can be printed by the printing device 200. The engine control unit 304 controls a series of printing operations performed by the printing device 200. The print job is processed on a page-by-page basis and printed.

[0027] The sensor control unit 305 controls the sensor 220 to measure the density of the patch formed on the paper after printing for the page for which the sensor measurement instruction was received, and obtains color measurement data. The data transmission / reception unit 306 controls data transmission / reception with the image processing device 20. Examples of data to be transmitted / received include print job data and setting registration information stored in the image forming device. The interrupt adjustment interval setting unit 307 sets the interval for interrupt printing of the adjustment chart.

[0028] FIG. 8 is an example of a UI screen for setting an interrupt adjustment interval according to this embodiment. This UI screen 801 is generated by the interrupt adjustment interval setting unit 307 and is displayed on the display unit 132 via the UI control unit 301. 802 represents interval information for printing an adjustment chart required to perform adjustment. The setting is accepted from the operator via the input unit 131. Here, the number of prints is specified as the interrupt interval information. In this UI screen 801, a button 803 or a button 804 is operated to accept a setting change, but for example, a UI that displays a numeric keypad and accepts a numerical value directly may be used. When the operator presses an OK button 805, the interrupt adjustment interval setting unit 307 notifies the interrupt adjustment execution unit 309, which will be described later, of the specified information and ends this UI screen 801. When a cancel button 806 is pressed, the interrupt adjustment interval setting unit 307 immediately ends this UI screen 801.

[0029] An interruption adjustment chart determination unit 308 determines the patch layout configuration of the adjustment chart to be inserted based on information from the page image analysis unit 302 and the page image control unit 304. Details will be described later. An interruption adjustment chart printing control unit 309 performs control for executing interrupt printing. In order to print a measurement chart at a specified interval, it performs processes related to printing of the adjustment chart, such as counting and clearing the number of printed pages and generating an adjustment chart image. An interruption adjustment execution unit 310 obtains color measurement data (color measurement results) from the sensor 220 and calculates a correction value for gradation correction. It updates the gradation correction data based on the correction value.

[0030] The print mode switching unit 311 is a part of the engine control unit 304, and controls mode switching of the printing operation performed by the printing device 200. The timing of switching the print mode is, for example, defined in the engine control unit 304 as the number of sheets for which black and white page images are continuously printed, and when that number is reached, switching is performed from the color image formation mode to the black and white image formation mode. Also, when printing a color page image in the black and white image formation mode, switching is immediately performed from the black and white image formation mode to the color image formation mode.

[0031] Here, the print mode control of the printing apparatus 200 will be described.

[0032] In this embodiment, the printing device 200 has a color image forming mode capable of both color printing and black and white printing, and a black and white image forming mode capable of only black and white printing, as printing modes. The printing mode switching unit 311 executes switching between the respective printing modes by means described later.

[0033] In the color image formation mode, images are formed with all of the K, C, M, and Y photosensitive drums 201K, 201C, 201M, and 201Y in contact with the intermediate transfer belt 209. All of the photosensitive drums 201 are in a ready state in which image formation can be performed immediately. In this printing mode, color printing and black-and-white printing can be performed, but even in black-and-white printing, all of the photosensitive drums 201 are operated in a ready state.

[0034] In the black-and-white image forming mode, the C, M, and Y photosensitive drums 201C, 201M, and 201Y are separated from and stopped by the intermediate transfer belt 209, and only the K photosensitive drum 201K is in contact with the intermediate transfer belt 209 to form an image. Only the K photosensitive drum 201K is in a ready state where image formation can be performed immediately. In this printing mode, black-and-white printing is possible, but color printing is not possible. When color printing is instructed during this printing mode control, the printing device 200 needs to switch control so that all the photosensitive drums 201 are in contact with the intermediate transfer belt 209. The switching operation is performed after waiting for the completion of image formation and transfer to paper for all pages proceeding in parallel on the intermediate transfer belt 209, and after the rotation of each photosensitive drum 201 is resumed, it is brought into contact with the intermediate transfer belt 209. Therefore, the switching operation takes a certain amount of time. In the black-and-white image forming mode, printing is performed using a recording material of only black (K).

[0035] Here, the means for stopping the photosensitive drum 201 from the intermediate transfer belt 209 has been described as the control for the black-and-white image formation mode. However, the control means is not limited to this. Other means may be used, such as a means for stopping the primary transfer roller 210 from the intermediate transfer belt 209 in addition to the photosensitive drum 201, or a means for cutting off the power supply to the exposure device 203 or the development device 204.

[0036] <Software configuration of image processing device> 3(b) is a block diagram of a RIP controller 140 which is a software module configuration of the image processing device 20. These software modules are stored as programs in the HDD 144, and are read into the RAM 143 and executed by the CPU 141. A UI control unit 341 controls the display of the display unit 152 in the operation unit 150 and controls the input of various setting information set by the input unit 151 via the operation unit I / F 148.

[0037] The print job management unit 342 manages print job data received from an operator. Specifically, it performs processes such as retrieving print jobs stored in the HDD 144, reflecting print job setting changes made by the operator, and managing the history of printed jobs. Generally, a print management application is provided to allow the operator to easily execute a series of processes.

[0038] 9 is an example of a UI screen of a print management application according to this embodiment. This UI screen 901 is managed and generated by the print job management unit 342, and is displayed on the display unit 152 via the UI control unit 341. A job queue 902 represents a job queue that displays information about print jobs received by the print processing device 20. Here, the name of the print job, the number of pages of the print job, information about the number of copies, information about whether interrupt adjustment described below is enabled, and information about whether the print job has been processed are displayed. The information displayed is not limited to this, and any item set in the print job, such as color / monochrome information or paper information, may be displayed.

[0039] When the operator selects a target print job and presses one of the buttons 903 to 905, the print job management unit 342 executes processing corresponding to the button. When the print button 903 is pressed, print processing of the selected print job is started, and when the processing is completed, print data is sent to the image forming apparatus 10. When the property button 904 is pressed, a UI screen for setting print settings of the selected print job is displayed. There are various items for print settings. For example, there are print paper to be used for the print job, layout such as page imposition, and settings related to color and image processing. The print setting items set here are notified to the print job management unit 342. When the delete button 905 is pressed, the data of the selected print job is deleted from the queue.

[0040] 10 is an example of a UI screen for configuring settings related to print paper, which is one of the print settings for a print job. This UI screen 1001 is generated by the print job management unit 342 and displayed on the display unit 152 via the UI control unit 341.

[0041] In this UI, 1002 indicates the paper type, 1003 indicates the paper size, and 1004 indicates the paper catalog information. Each of these accepts settings from the operator via the input unit 151. Here, a paper catalog is a collection of arbitrary paper information given a name, and is managed by the print job management unit 342, but may also be created by the operator. When a paper catalog is selected in 1004, the paper type 1002 and size 1003 indicate the information set in the paper catalog. When an OK button 1005 is pressed, the print job management unit 342 sets the input paper information as job setting information. When a cancel button 1006 is pressed, the print job management unit 342 ends this UI screen 1001.

[0042] The print job processing unit 343 performs processes required for executing print processing, such as analyzing the print job received from the operator, expanding it into image data, and compressing and expanding the image. The data transmission / reception unit 344 manages the transmission and reception of various data with the image forming apparatus 10. The print job data generated by the print job processing unit 343 is transmitted to the image forming apparatus 10 by the data transmission / reception unit 344. The data transmission / reception unit 344 also manages the transmission and reception of data with the client PC 30 connected via the external network 40. The interrupt adjustment setting unit 345 sets whether or not to perform interrupt adjustment for the print job. This setting is one of the print setting items that are displayed and set by pressing the properties button 904 of the print management application 901 described above.

[0043] 11 shows an example of a UI screen for performing print settings for a print job according to this embodiment. This UI screen 1101 is managed and created by the interrupt adjustment setting unit 345 on the print job management unit 342, and is displayed on the display unit 152 via the UI control unit 341. 1102 is a check box for specifying whether or not to perform interrupt adjustment. When the operator checks the check box 1102, interrupt adjustment is enabled for the print job, and when the check box is unchecked, interrupt adjustment is disabled. When an OK button 1103 is pressed, the state of the currently displayed check box 1102 is notified to the print job management unit 342, and this UI screen 1101 is terminated. When a cancel button 1104 is pressed, the interrupt adjustment setting unit 345 immediately terminates this UI screen 1101.

[0044] <Print job execution flow according to the first embodiment> The execution flow of a print job involving interrupt adjustment according to this embodiment will be described. The execution of a print job is explained in order, since processing is performed by both the image processing device 20 and the image forming device 10. First, the processing by the image processing device 20 will be explained.

[0045] 4 is a flow diagram showing an execution flowchart in the image processing device 20. This flowchart is realized by reading a program stored in the HDD 144 of the image processing device 20 into the RAM 143 and executing it by the CPU 141. This flowchart starts when the print button 903 is pressed on the print management application UI screen 901 with a print job selected.

[0046] In S401, the print job management unit 342 reads the target print job data. In the following S402, the print job management unit 342 reads print setting information related to the print settings. In addition to the items described above in FIG. 10 and FIG. 11, there are other items such as page layout settings for the print job and settings related to a CMS (Color Management System) such as a color profile. Furthermore, the print setting information related to the print settings includes many items such as settings related to image processing correction such as halftones and settings related to the operation of a finishing device. Of course, the print settings for a print job are not limited to the items listed here, and there are various other setting items.

[0047] In S403, the print job processing unit 343 performs RIP processing of the print job. Here, RIP (Raster Image Processor) processing of the print job refers to analyzing the submitted print job, performing necessary processing such as color conversion according to the print setting information read in S402, and developing the print job into rasterized image data. After this processing is performed, the print job becomes a group of image data in units of pages.

[0048] In the next S404, the print job management unit 342 transmits the processed print job data to the image forming apparatus 10 via the data transmission / reception unit 344. The print job data includes the expanded page image data group as well as print job setting item information required for processing in the image forming apparatus 10. When S404 ends, the print job management unit 342 ends this flowchart.

[0049] Next, a description will be given of the processing of the image forming apparatus 10. First, a print mode switching method for switching the print mode of the printing apparatus 200 will be described.

[0050] 5 is a flow diagram showing an execution flowchart of the print mode switching unit 311 of the engine control unit 304 of the device controller 100 in the image forming apparatus 10. This flowchart is realized by reading a program stored in the HDD 114 of the image forming apparatus 10 into the RAM 113 and executing it by the CPU 111.

[0051] This flowchart starts when page image data that has been print-processed by the page image control unit 303 is printed by the engine control unit 304. In the print job processing flow described later, this flow is executed when the flow proceeds to steps S6104 and S6205.

[0052] In S501, the print mode switching unit 311 determines the color configuration (color attribute) of the read page image data. Here, the color configuration is the number of colors used to configure the page image data. In the printing device 200 according to this embodiment, four toners, C, M, Y, and K, can be used, and if the page image data is configured with only K toner, the color configuration is determined to be "black and white." Also, if the page image data is configured with a configuration other than "black and white," that is, if it contains even a small amount of C, M, or Y toner, the color configuration is determined to be "color." If the page configuration is determined to be "color" in S501, the process proceeds to S502.

[0053] In S502, the print mode switching unit 311 determines the current print mode of the printing device 200. If the print mode is determined to be color in S502, the process proceeds to S504, and if it is determined to be black and white, the process proceeds to S503. In S503, the print mode switching unit 311 switches the print mode of the printing device 200 to the color image formation mode through the engine control unit 304. The switching control means is as described above. Because the color composition of the page image to be printed is color, printing cannot be performed if the print mode remains in the black and white image formation mode. Therefore, the print mode is switched at this timing.

[0054] In S504, the engine control unit 304 executes printing of the page image to be printed upon receiving an instruction from the print mode switching unit 311. In the following S505, the print mode switching unit 311 clears the black and white consecutive counter to zero.

[0055] Here, the black and white consecutive counter will be explained. The black and white consecutive counter is information managed by the print mode switching unit 311, stored in the HDD 114 or ROM 112, and defined as a condition for switching the print mode of the printing device 200. In this embodiment, it is defined as information on the number of consecutive pages, and the value is, for example, 100 sheets.

[0056] Although the print mode switching unit 311 has been described as holding the value as a fixed value, the present invention is not limited to this. For example, the print mode switching unit 311 may dynamically set the print mode by accepting input from an operator or administrator via an operation setting screen (not shown). Furthermore, the print mode switching unit 311 has been described as information on the number of consecutive pages, but the print mode switching unit 311 may define a different index, such as elapsed time or the number of jobs. When S505 ends, the print mode switching unit 311 ends this flow.

[0057] Returning to S501, if the page configuration is determined to be "black and white" in S501, the process proceeds to S506. In S506, similar to S504, the engine control unit 304 receives an instruction from the print mode switching unit 311 and executes printing of the page image to be printed. Since the color configuration of the page image data is black and white, printing can be executed as is regardless of the color image forming mode of the printing device 200.

[0058] In the next S507, the print mode switching unit 311 determines the current print mode of the printing apparatus 200. If the print mode is determined to be color in S507, the process proceeds to S508, and if the print mode is determined to be black and white, the process ends.

[0059] In S508, the print mode switching unit 311 increments the black and white consecutive counter. When the print mode of the printing device 200 is in the color image forming mode and a black and white page image is printed, the black and white consecutive counter is incremented.

[0060] Furthermore, in S509, the print mode switching unit 311 judges whether the black and white consecutive counter has reached a predetermined number. In this embodiment, the predetermined number is set to, for example, 100 sheets. If the counter reaches that number, the process proceeds to S510. If the counter has not yet reached that number, the process ends. In S510, the print mode switching unit 311 switches the print mode of the printing device 200 to a black and white image forming mode through the engine control unit 304. In order to prevent consumption of unused color toner and wear of components due to the continuous printing of a predetermined number of black and white image pages, the print mode is switched to black and white. The print processing flow of page image data has been described above. This flow is executed for all pages to be printed.

[0061] Next, a flow of executing a print job involving interrupt adjustment will be described.

[0062] 6 is a flow diagram showing an execution flowchart of a print job involving interrupt adjustment in the image forming apparatus 10. This flowchart is realized by a program stored in the HDD 114 of the image forming apparatus 10 being read into the RAM 113 and executed by the CPU 111. This flowchart starts when the print processing of the print job in the image processing device 20 is completed in S404 and image data is received.

[0063] In S6001, the page image analysis unit 302 analyzes the received print job. Here, the image data group and the contents of the setting item information of the received print job are confirmed. In S6002, the page image analysis unit 302 determines whether the interrupt adjustment setting is enabled. If it is enabled, the process proceeds to S6003. In S6003, the interrupt adjustment chart printing control unit 309 reads the interrupt adjustment counter information and the adjustment interval information from the interrupt adjustment chart printing control unit 309.

[0064] If the interrupt adjustment setting is invalid in S6002, or after the process of S6003 is completed, the process proceeds to S6004. In S6004, the page image control unit 303 selects the first page image data of the received and analyzed print job. In the following S6005, the page image control unit 303 executes the print process of the selected page.

[0065] Here, the page print processing executed in S6005 will be described with reference to Fig. 19(a). Fig. 19(a) is a flow diagram showing the print processing of a page image in the image forming apparatus 10. This flow chart is realized by reading a program stored in the HDD 114 of the image forming apparatus 10 into the RAM 113 and executing it by the CPU 111.

[0066] In S6101, the page image control unit 303 reads a tone correction table, which will be described later.

[0067] Next, in S6102, the page image control unit 303 executes a tone correction process.

[0068] Here, the tone correction process will be described. The tone correction process is a correction process for keeping the output density of the image forming device 10 constant. In the printing device 200 that controls the toner and ink to perform printing, the printed output density is easily affected by the paper to be printed and the temperature and humidity of the environment in which the device is installed, and the printed output density always changes. Even if the page is created by the same image processing, if the output density of the printing device 200 changes, there will be a difference in the output image quality when printed. To always obtain stable output image quality, there is a tone correction process. The tone correction process is a process for correcting print data so that the toner or ink components become a predetermined optimal output. In general, a lookup table (LUT) is provided for converting each toner or ink component into an output signal value that is an appropriate output for the input signal value, and correction using the LUT is performed when the print data processing is executed. Here, the LUT for conversion is called a tone correction table.

[0069] The principle of the tone correction process will be described with reference to Fig. 13. The data shown here is stored in the HDD 114 and managed by the page image control unit 303.

[0070] 13A shows an example of a table that defines a target density that is a standard for output density for each color. Here, information on optimal output density values ​​is defined for 10 input signals ranging from 10% to 100%. This target information may be information that is defined in advance by the printer vendor, or information that is actually measured by an operator and registered via the operation unit 130.

[0071] Fig. 13(b) shows an example of the measurement value obtained by printing a gradation patch image created from 10 input signal values ​​at a certain point in time and reading its density. This measurement value becomes the current output density of the printing device 200. The page image control unit 303 calculates a gradation correction table from the gradation target (reference value) (Fig. 13(a)) and the measurement value (Fig. 13(b)).

[0072] FIG. 13(c) is an example in which the difference in density is calculated as the correction value. The difference may be used as the correction value as it is, or a value obtained by performing a certain processing such as multiplying by a constant may be used as the correction value. Based on this correction value, a signal value that has the same density as the target density of the input signal value is associated as an output signal value to generate a tone correction table. In this example, an explanation is given using an example of 10 input signal values, but this is not limited to this. The more signal values ​​used, the higher the accuracy of correction, but the number of patches required for measurement increases. In addition, since the output density differs depending on the paper to be printed, there are cases in which a tone target and a tone correction table are provided for each paper. Here, the tone correction process for all four colors has been explained, but it is not necessary to perform all at once. Only one or more arbitrary colors may be performed. In this embodiment, correction process is performed for all four colors when the configuration of the adjustment chart described later is four colors, and for black only when it is black and white.

[0073] According to the above-described processing, in S6102, the page image control unit 303 converts the signal values ​​of the page image to be processed using the tone correction table read in S6101.

[0074] In the next step S6103, the page image control unit 303 executes halftone processing. Halftone processing is processing for converting the signal value of a page image expressed in multiple tones to a smaller number of tones that can be output by the printing device 200. It is generally known as a technology for expressing multiple tones in a pseudo manner while reducing the number of tones by expressing one pixel in a page image in multiple areas. In step S6104, the engine control unit 304 forms the page image data, which has been converted into a state printable by the printing device 200, on a sheet of paper and executes printing processing. In this embodiment, the printing mode switching unit 311 also performs processing for switching the printing mode of the printing device 200 according to the color configuration of the page image. The flow of the printing process is as described in FIG. 5. When the print output of the target page is completed, this flow ends.

[0075] Returning to the flowchart in FIG. 6, in the following S6006, the page image control unit 303 determines whether the interrupt adjustment setting is enabled, as in S6002.

[0076] If the interrupt adjustment setting is invalid in S6006, the process proceeds to S6007, where the page image control unit 303 determines whether the processed page is the final page of the print job. If it is determined that it is the final page, this flow ends. If it is determined that it is not the final page, the next page is selected in the following S6008, and the process returns to S6005. If the interrupt adjustment setting is valid in S6006, the process proceeds to S6009. In S6009, the interrupt adjustment chart printing control unit 309 performs an increment operation to increase the adjustment counter read in S6003 by one.

[0077] In S6010, the interrupt adjustment chart printing control unit 309 determines whether the adjustment counter has reached the setting value of the adjustment interval read in S6003. If the adjustment interval value has been reached, the adjustment page printing process is executed in the following S6011 and onwards. If the adjustment counter has not been reached, the process proceeds to S6007 and the above-mentioned process continues.

[0078] If the adjustment counter reaches the adjustment interval value in S6010, the interruption adjustment chart determination unit 308 and the interruption adjustment chart print control unit 309 generate an interruption adjustment page in S6011.

[0079] Here, the determination and generation of the interruption adjustment chart executed in S6011 will be described. Fig. 7 is a flow diagram showing a process flow related to the generation of the interruption adjustment page in S6011. This flow chart is realized by reading a program stored in HDD 114 of image forming apparatus 100 into RAM 113 and executing it by CPU 111.

[0080] In S701, the interruption adjustment chart determination unit 308 analyzes the page image where the adjustment counter has reached the adjustment interval value. That is, it analyzes the page image of the predetermined number. Specifically, it analyzes the color configuration information of the target page image. The color configuration information is as described in S501 above.

[0081] In S702, the interruption adjustment chart determination unit 308 determines whether the color configuration of the page image is color or black and white based on the analysis result of S701. If it is color, the process proceeds to S703, and if it is black and white, the process proceeds to S704. If it is determined to be color in S702, the process proceeds to S703, where the interruption adjustment chart determination unit 308 selects a gradation patch for color. The gradation patch will be described later.

[0082] If it is determined to be black and white in S702, the process proceeds to S704, where the interruption adjustment chart determination unit 308 selects a gradation patch for black and white. The gradation patch will be described later. In the following S705, the interruption adjustment chart determination unit 308 uses the gradation patch selected in S703 or S704 to create page image data for the adjustment chart.

[0083] Here, the page of the adjustment chart to be generated will be described with reference to Fig. 12. Figs. 12(a) and (b) are diagrams showing an example of a page image (gradation pattern image) of the adjustment chart. This chart is determined and generated by the interruption adjustment chart determination unit 308. Page image 1201 is an example of a page image when a color gradation patch is selected in S703, and page image 1211 is an example of a page image when a black and white gradation patch is selected in S704.

[0084] In the page image 1201, gradation patches expressed by four colors of toner are arranged at predetermined positions within the page (1202 to 1205). In this example, each toner is configured as 10 gradation patches with stepwise different densities, but as described in the gradation correction process above, the number of patches is not limited to this. The color measurement sensor 220 in FIG. 2 indicates a sensor installed on the paper transport path, and the page image is arranged with 1202 to 1205 arranged so as to pass through the position of the installed sensor 220. Here, the sensor 220 has been described as being configured to be fixed and arranged in two units, but the number and positions of the sensors 220 are not limited to this. Only one sensor may be fixedly arranged at an arbitrary location, four sensors may be fixedly arranged, or one or more sensors may be installed in a movable state. Furthermore, the adjustment chart to be generated may be arranged in a layout that allows the sensor 220 to read the gradation patches depending on the number and installation state of the sensors 220. Furthermore, as one of the factors in the specifications that the sensor 220 can read, the layout of the tone patches arranged on the adjustment chart may be changed depending on the size and type of paper.

[0085] In the page image 1211, gradation patches expressed in one color of black toner are arranged at predetermined positions within the page (1212-1213). In this example, the black toner is configured as 20 gradation patches with gradually differing densities, but as described above, the number and layout of the gradation patches arranged are not limited to this. When the above processing of S705 is completed, the process flow proceeds to S6012.

[0086] In the next step S6012, the interruption adjustment chart print control unit 309 executes printing processing for the interruption adjustment chart. Here, the interruption adjustment chart printing processing executed in step S6012 will be described with reference to FIG.

[0087] 19B is a flow diagram showing an interruption adjustment chart printing process in the image forming apparatus 10. This flow chart is realized by a program stored in the HDD 114 of the image forming apparatus 10 being read into the RAM 113 and executed by the CPU 111.

[0088] At S6201, the interruption adjustment chart printing control unit 309 reads the current gradation correction table. At S6202, the interruption adjustment chart printing control unit 309 executes gradation correction processing. At S6203, the interruption adjustment chart printing control unit 309 executes halftone processing. At S6204, the interruption adjustment chart printing control unit 309 issues an instruction to the sensor control unit 305 to control the sensor 220 to measure the density of the gradation patch formed and printed on the adjustment chart 1201 or 1211.

[0089] In S6205, the engine control unit 304 forms a page image (gradation pattern image) of the adjustment chart on paper and prints it out. At the same time, the sensor control unit 305 measures the density of the patch. In this embodiment, the print mode switching unit 311 also switches the print mode of the printing device 200 depending on the color composition of the page image. The flow of the print process is as described in FIG. 5. When printing is completed, this flow ends.

[0090] Returning to the flowchart of Fig. 6, in the next step S6013, the interrupt adjustment execution unit 310 receives the measurement results of the adjustment patch measured by the sensor 220. In the next step S6014, the interrupt adjustment execution unit 310 generates tone correction data. Here, the tone correction data generation process executed in S6014 will be described with reference to Fig. 19(c). The principle of tone correction is as described above.

[0091] 19C is a flow diagram showing an interruption adjustment chart printing process in the image forming apparatus 10. This flow chart is realized by a program stored in the HDD 114 of the image forming apparatus 10 being read into the RAM 113 and executed by the CPU 111.

[0092] In S6301, the interrupt adjustment execution unit 310 reads the gradation correction target corresponding to the paper on which the adjustment chart is printed from the page image control unit 303. In S6302, the interrupt adjustment execution unit 310 reads the measurement results of the adjustment patch by the sensor 220 received in S6013. In S6303, the interrupt adjustment execution unit 310 calculates the difference between the gradation target and the measurement value. In S6304, the interrupt adjustment execution unit 310 generates a new gradation correction table from the calculated difference. As described above, a new gradation correction table is generated every time an interrupt occurs and an adjustment chart is output.

[0093] As described above, the new correction table to be generated may be changed according to the color configuration of the adjustment patch measured in S6013. In this embodiment, if the adjustment chart is configured with four colors, the tone correction table is generated for all four colors, and if it is configured with black and white, the tone correction table is generated for only black.

[0094] 6, in the next step S6015, the interruption adjustment execution unit 310 updates and saves the newly generated gradation correction table. In the next step S6016, the interruption adjustment chart printing control unit 309 clears the interruption adjustment counter, and the process proceeds to step S6007 to continue the above-mentioned process.

[0095] As described above, by executing this flowchart, an adjustment chart is generated and printed each time the number of printed pages reaches the set adjustment interval during printing of a print job for which adjustment settings are enabled. A new gradation correction table is generated and continuously updated based on the measurement values ​​obtained by measuring the gradation patches printed on the adjustment chart. The updated gradation correction table is applied from the printing process immediately after the update, making it possible to achieve stable output image quality during printing of the print job.

[0096] As described above, according to the present embodiment, in a printing system that prints an adjustment chart during execution of a print job and applies the results of measuring the patch density of the chart to a gradation correction process, the gradation patches of the adjustment chart are changed according to the color composition of the print job. This makes it possible to switch between color adjustment when the page of the print job is composed of color images and black and white adjustment when the page is composed of black and white images. As a result, it is possible to prevent unnecessary consumption of toner and wear and tear on device components.

[0097] [Second embodiment] In the first embodiment, a flow for determining the configuration of the gradation patches of the adjustment chart based on the analysis results of the counter arrival page image was described. In this embodiment, a method for determining the configuration of the adjustment chart using a method different from that of the first embodiment will be described. Since the hardware configuration, software configuration, and print processing flow are the same as those of the first embodiment, figures and descriptions will be omitted. Only the differences will be described below. In this embodiment, the process of generating an interruption adjustment page S6011 in the flow of FIG. 6 is changed.

[0098] 14 is a flow diagram showing a process flow for generating an interrupt adjustment page in step S6011 according to this embodiment. This flow chart is implemented by a program stored in HDD 114 of image forming apparatus 100 being loaded into RAM 113 and executed by CPU 111.

[0099] In S1401, the interrupt adjustment chart determination unit 308 checks the print mode (image formation mode) of the printing apparatus 200 controlled by the engine control unit 304. The print mode (image formation mode) is dynamically switched in accordance with the processing flow described in Fig. 5, and is in either the color image formation mode or the black and white image formation mode. If it is the color image formation mode, the process proceeds to S1402, and if it is the black and white image formation mode, the process proceeds to S1403.

[0100] If the color image forming mode is determined in S1401, the process proceeds to S1402, where the interrupt adjustment chart determination unit 308 selects a color gradation patch. If the black-and-white image forming mode is determined in S1401, the process proceeds to S1403, where the interrupt adjustment chart determination unit 308 selects a black-and-white gradation patch.

[0101] S1404 is the same as S705, and therefore a description thereof will be omitted. Also, the printing flow after the generation of the adjustment chart in S6011 is the same as in the first embodiment, and therefore a description thereof will be omitted.

[0102] As described above, according to this embodiment, the interrupt adjustment chart determination unit 308 changes the gradation patches of the adjustment chart according to the print mode of the printing device 200 controlled by the engine control unit 304. This makes it possible to switch between color adjustment when the page of the print job is composed of a color image and black and white adjustment when the page is composed of a black and white image. As a result, it is possible to prevent unnecessary consumption of toner and wear and tear of device components.

[0103] Furthermore, in a configuration in which the color / black and white printing mode can be switched, downtime occurs as the printing mode is switched from black and white to color image formation mode in order to print color patches; however, according to this embodiment, this downtime can be prevented.

[0104] [Third embodiment] In the first and second embodiments, the configuration has been described in which the device controller 100 of the image forming apparatus 10 generates and controls the interrupt adjustment chart for implementing the interrupt adjustment.

[0105] In this embodiment, a configuration will be described in which the interruption adjustment chart is generated by the RIP controller 140 in the image processing device 20. Only the differences will be described below.

[0106] The hardware configuration is the same as in the first embodiment, so the diagram and description will be omitted.

[0107] 15A is a block diagram of a device controller 100 which is a software module configuration of the image forming apparatus 10. These software modules are stored as programs in the HDD 114, and are read by the CPU 111 into the RAM 113 and executed.

[0108] The controls of a UI control unit 1501, a page image analysis unit 1502, a page image control unit 1503, an engine control unit 1504, and a sensor control unit 1505 are the same as those of the blocks 301 to 305 of the same names in Fig. 3, and therefore descriptions thereof will be omitted. The controls of an interrupt adjustment interval setting unit 1507, an interrupt adjustment execution unit 1508, and a print mode switching unit 1509 are the same as those of the blocks 307, 310, and 311 of the same names in Fig. 3, and therefore descriptions thereof will be omitted.

[0109] A data transmission / reception unit 1506, which is the same as the control unit 306, controls data transmission / reception with the image processing device 20. The data to be transmitted / received is, for example, print job data, setting registration information stored in the image forming device, etc. Furthermore, in this embodiment, the setting value set in an interrupt adjustment interval setting unit 1507 and print mode information of the printing device 200 are transmitted to the image processing device 20.

[0110] 15B is a block diagram relating to a RIP controller 140 which is a software module configuration of the image processing device 20. These software modules are stored as programs in a HDD 144, and are read into a RAM 143 by a CPU 141 and executed.

[0111] The controls of the UI control unit 1541, print job management unit 1542, print job processing unit 1543, and interrupt adjustment setting unit 1545 are the same as those of the blocks 341 to 343 and 345 with the same names, and therefore descriptions thereof will be omitted.

[0112] The data transmission / reception unit 1544 is the same as the control unit 344, and manages the transmission and reception of various data with the image forming apparatus 10. The print job data generated by the print job processing unit 1543 is transmitted to the image forming apparatus 10 by the data transmission / reception unit 1544. The data transmission / reception unit 1544 also manages the transmission and reception of data with the client PC 30 connected via the external network 40. Furthermore, in this embodiment, the setting value set in the interrupt adjustment interval setting unit 1507 and print mode information of the printing apparatus 200 are received from the image forming apparatus 10.

[0113] The interruption adjustment chart determination unit 1546 is the same as the interruption adjustment chart determination unit 308 of the device controller 100 in the first and second embodiments. It receives information necessary for determination from the image forming apparatus 10 and determines the patch layout configuration of the interruption adjustment chart.

[0114] The interruption adjustment chart printing control unit 1547 is the same as the interruption adjustment chart printing control unit 309 of the device controller 100 in the first and second embodiments. In order to print a measurement chart at a specified interval received from the image forming apparatus 10, the interruption adjustment chart printing control unit 1547 counts and clears the number of pages of a RIPped print job, generates an adjustment chart image, and performs processes related to inserting pages into the print job.

[0115] 16 is a flow diagram showing an execution flowchart of a print job involving interrupt adjustment in the image processing device 20 according to this embodiment. This flowchart is realized by reading a program stored in the HDD 144 of the image processing device 20 into the RAM 143 and executing it by the CPU 141.

[0116] The following description will focus on the differences from the process flows described in FIGS. 4 to 6 in the first and second embodiments.

[0117] S1601 to S1603 are the same as S401 to S403 in the first and second embodiments, and therefore the description will be omitted. In S1604, the print job processing unit 1543 analyzes the image page group after RIP processing and the print setting information. Next, in S1605 to S1607, the print job processing unit 1543 performs the same processing as S6002 to S6004.

[0118] In S1608, the print job management unit 1542 transmits the processed page image to the image forming apparatus 10 via the data transmission / reception unit 1544. The print job data includes setting item information of the print job required for processing in the image forming apparatus 10 in addition to the expanded page image data.

[0119] Steps S1609 to S1611 are processed by the print job management unit 1542. Since the contents of steps S6006 to S6008 executed by the page image control unit 303 in the first and second embodiments are the same as those in the first and second embodiments, a description thereof will be omitted.

[0120] S1612 and S1613 are processed by the interruption adjustment chart printing control unit 1547. Description will be omitted as they are the same as the contents executed by the interruption adjustment chart printing control unit 309 in S6009 and S6010 in the first and second embodiments. S1614 is processed by the interruption adjustment chart determination unit 1546. They are the same as the contents executed by the interruption adjustment chart determination unit 308 in S6011 in the first and second embodiments.

[0121] Furthermore, in the first and second embodiments, the interruption adjustment chart is determined by the interruption adjustment chart determination unit 308 in the image forming apparatus 10 through the process flows described in Fig. 7 and Fig. 14. In this embodiment, the interruption adjustment chart is determined by the interruption adjustment chart determination unit 1546 in the image processing apparatus 20. The method is the same as in the first and second embodiments, and therefore description thereof will be omitted.

[0122] In S1615, the print job management unit 1542 transmits the processed page image to the image forming apparatus 10 via the data transmission / reception unit 1544. The print job data includes information identifying the page as an adjustment page in addition to the expanded page image data. S1616 is processed by the interruption adjustment chart printing control unit 1547. This is the same as the content executed by the interruption adjustment chart printing control unit 309 in S6016 in the first and second embodiments, and therefore a description thereof will be omitted.

[0123] 17 is a flow diagram showing an execution flowchart of a print job involving interrupt adjustment in the image forming apparatus 10. This flowchart is realized by a program stored in the HDD 114 of the image forming apparatus 10 being read into the RAM 113 and executed by the CPU 111.

[0124] 4 to 6 in the first and second embodiments will be described with emphasis on the differences. S1701 and S1702 are processed by the page image analysis unit 1502 and the page image control unit 1503. Since the contents are the same as those executed by the page image analysis unit 302 and the page image control unit 303 in S6001 and S6004 in the first and second embodiments, the description will be omitted.

[0125] In S1703, the page image analysis unit 1502 determines whether the selected page is a page image for adjustment based on the information attached to the adjustment page transmitted in S1615.

[0126] If it is determined in S1703 that the page is not an adjustment page, the process proceeds to S1704, where the page image control unit 1503 executes print processing for the target page. This is the same processing as S6005 in the first and second embodiments, and the details are the same as those described in FIG. 19A, so a description thereof will be omitted. S1705 and S1706 are processed by the page image control unit 1502. The details are the same as those executed by the page image control unit 303 in S6007 and S6008 in the first and second embodiments, so a description thereof will be omitted.

[0127] S1707 is processed by the interruption adjustment chart printing control unit 1547. This is the same as the processing executed by the interruption adjustment chart printing control unit 309 in S6011 in the first and second embodiments, and the details are the same as those described in FIG. 19B, so a description thereof will be omitted.

[0128] Steps S1708 to S1710 are processed by the interruption adjustment chart print control unit 1547. Descriptions of steps S1708 to S1710 will be omitted since they are the same as those executed by the page image control unit 303 in steps S6013 to S6015 in the first and second embodiments. In the present embodiment, a configuration has been described in which the interruption adjustment chart is generated and controlled by the image processing device 20.

[0129] As described above, according to the present embodiment, in a printing system that prints an adjustment chart during execution of a print job and applies the results of measuring the patch density of the chart to a gradation correction process, the gradation patches of the adjustment chart are changed according to the color composition of the print job. This makes it possible to switch between color adjustment when the page of the print job is composed of color images and black and white adjustment when the page is composed of black and white images. As a result, it is possible to prevent unnecessary consumption of toner and wear and tear on device components.

[0130] (Other embodiments) The present invention can also be realized by a process in which a program for implementing one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) that implements one or more of the functions.

Claims

1. An image forming apparatus capable of switching between a color image forming mode in which printing is performed using a plurality of recording materials including chromatic color recording materials and a black-and-white image forming mode in which printing is performed using a single black recording material without using chromatic color recording materials, A printing means for printing an image; An enabling means for enabling the setting of interrupt moderation; a means for not incrementing an adjustment counter each time one page is printed when the setting is not enabled, and for incrementing the adjustment counter each time one page is printed when the setting is enabled; a control means for causing the printing means to print a gradation pattern image when the adjustment counter reaches a predetermined value; a color measurement means for reading and measuring the color of the gradation pattern image printed by the printing means; a generating means for generating gradation correction data based on a color measurement result of the gradation pattern image by the color measuring means and a reference value; a correction unit that performs gradation correction on image data using the gradation correction data generated by the generation unit, acquiring an image forming mode of the image forming apparatus when the adjustment counter reaches the predetermined value; an image forming apparatus characterized in that, when the acquired image forming mode is a color image forming mode, a color gradation pattern image including a plurality of patch images having gradually differing densities is printed using the chromatic color recording material, and, when the acquired image forming mode is a black-and-white image forming mode, a black-and-white gradation pattern image is printed using the black monochrome recording material without using the chromatic color recording material.

2. 2. The image forming apparatus according to claim 1, wherein, when the acquired image forming mode is the color image forming mode, the plurality of patch images are printed using at least a first color recording material and a second color recording material different from the first color recording material.

3. 3. The image forming apparatus according to claim 1, wherein the plurality of recording materials including chromatic color recording materials include at least two of a cyan toner, a yellow toner, a magenta toner, and a black toner.

4. 4. The image forming apparatus according to claim 1, further comprising an operation unit that receives the predetermined value.

5. An image forming method for an image forming apparatus capable of switching between a color image forming mode in which printing is performed using a plurality of recording materials including chromatic color recording materials and a black-and-white image forming mode in which printing is performed using a black monochrome recording material without using chromatic color recording materials, comprising: a printing step of printing the image by a printing means; an enabling step for enabling the interrupt moderation setting; a step of not incrementing an adjustment counter every time one page is printed when the setting is not enabled, and incrementing the adjustment counter every time one page is printed when the setting is enabled; a control step of causing the printing means to print a gradation pattern image when the adjustment counter reaches a predetermined value; a color measurement step of reading and measuring the gradation pattern image printed in the printing step; a generating step of generating gradation correction data based on a color measurement result of the gradation pattern image by the color measurement step and a reference value; a correction step of performing gradation correction on the image data using the gradation correction data generated by the generating step, acquiring an image forming mode of the image forming apparatus when the adjustment counter reaches the predetermined value; an image forming method characterized in that, when the acquired image forming mode is a color image forming mode, a color gradation pattern image including a plurality of patch images having gradually differing densities is printed using the chromatic color recording material, and, when the acquired image forming mode is a black-and-white image forming mode, a black-and-white gradation pattern image is printed using the black monochrome recording material without using the chromatic color recording material.

6. A program for causing a computer to execute the image forming method according to claim 5.

Images