JP2016103815A - Inspection device, threshold change method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inspection device, a threshold change method and a program, capable of easily changing threshold information for use for the inspection of a printed matter to a value according to user intention.SOLUTION: The inspection device includes: a reading image acquisition unit 402 which acquires a reading image obtained by reading a printed matter; a master image generation unit 403 which generates a reference image on the basis of the original image of a printed matter generation source; an inspection unit 404 which inspects the printed matter on the basis of threshold information composed of one or more types of thresholds, and a difference image indicative of a difference between the first reading image and the reference image; an identification unit 408 which identifies a region of the printed matter which produces contradiction between the inspection result and a confirmation result obtained by a user visual inspection; and a change unit 409 which changes the threshold information in a manner to cancel the contradiction in the region.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an inspection apparatus, a threshold value changing method, and a program.

  In production printing, there is a need to perform some kind of inspection on the print output of a printer. For example, a print output of a printer is read by a line sensor such as a camera or a scanner, and whether or not printing is normally performed is checked based on the read result and threshold information composed of one or more thresholds. There is an inspection device.

  As a technique for changing the threshold information as described above, for example, in Patent Document 1, an image defect is detected based on document image data and inspection image data, and the quality of a printed matter is determined based on a plurality of threshold values, Quality determination means for classifying into a defect class or an intermediate quality class having a quality between a good product class and a defect class, information on the level of image defects for each type of image defect in the printed matter, and each quality class of the printed matter Storage means for holding log information including information relating to the number of sheets, and display means for displaying the number of each quality class of the printed matter, the display means presents a display for changing the threshold value to the user, There is disclosed a printed matter inspection control device that re-edits and displays the number of each quality class according to the changed threshold value when the threshold value is changed by the user. That.

  However, in the conventional technology as described above, in order to change the threshold value information so as to obtain the inspection result intended by the user, specialized knowledge is required, which is very troublesome.

  The present invention has been made in view of the above, and it is an object of the present invention to provide an inspection apparatus, a threshold change method, and a program that can easily change threshold information used for inspection of printed matter to a value in accordance with a user's intention. And

  In order to solve the above-described problems and achieve the object, an inspection apparatus according to an aspect of the present invention includes a read image acquisition unit that acquires a first read image obtained by reading a printed material, and a source of the printed material. Based on a reference image generation unit that generates a reference image based on an image, threshold information including one or more types of thresholds, and a difference image that indicates a difference between the first read image and the reference image An inspecting unit for inspecting the printed matter, a specifying unit for specifying a region on the printed matter in which a contradiction occurs between the inspection result and a user's visual confirmation result, and the contradiction in the region is resolved. And a changing unit for changing the threshold information.

  According to the present invention, there is an effect that threshold information used for inspection of printed matter can be easily changed to a value according to the user's intention.

FIG. 1 is a block diagram illustrating a configuration of a print inspection system. FIG. 2 is a diagram illustrating a mechanical configuration of the print engine and the print inspection apparatus. FIG. 3 is a block diagram illustrating a hardware configuration example of the print inspection apparatus. FIG. 4 is a block diagram illustrating a functional configuration example of the engine controller, the print engine, and the print inspection apparatus. FIG. 5 is a flowchart illustrating a processing example of the print inspection apparatus. FIG. 6 is a diagram illustrating a screen example of the inspection result of the inspection unit. FIG. 7 is an explanatory diagram of an example of a gap region designation method. FIG. 8 is a chart illustrating threshold information held by the inspection unit. FIG. 9 is a chart showing type determination threshold information. FIG. 10 is an explanatory diagram of an example of a method for determining a vertical line defect candidate. FIG. 11 is an explanatory diagram of an example of a method for determining a defect candidate for a horizontal line. FIG. 12 is an explanatory diagram of an example of a technique for discriminating defect candidates for point defects. FIG. 13 is an explanatory diagram of an example of a changing method in the case where the threshold information is changed so as to become a non-defective region when the gap region is a defective region. FIG. 14 is an explanatory diagram of an example of a changing method in the case where the threshold information is changed so as to become a defective region when the gap region is a non-defective region. FIG. 15 is a flowchart illustrating a processing example of the print inspection apparatus after the processing example described in FIG. FIG. 16 is a diagram illustrating an example of a screen for information on the affected area. FIG. 17 is a diagram illustrating an example of a threshold information change confirmation screen. FIG. 18 is a block diagram illustrating a functional configuration example of the engine controller, the print engine, and the print inspection apparatus. FIG. 19 is an explanatory diagram of a method for designating a gap region on a printed material by a user giving a mark with a pen. FIG. 20 is an explanatory diagram of a method for identifying a gap region when a symbol is a mark with a pen. FIG. 21 is a flowchart showing the gap area specifying process when the symbol is a pen mark. FIG. 22 is a chart illustrating an RGB data table. FIG. 23 is a chart showing a specific example of the gap region list. FIG. 24 is an explanatory diagram of a method for specifying a gap region when a symbol is a mark by a sticky note. FIG. 25 is an explanatory diagram of a method for specifying a gap region when a symbol is a sticky note and a mark using a pen.

  Exemplary embodiments of an inspection apparatus, a threshold value changing method, and a program according to the present invention will be described below in detail with reference to the accompanying drawings.

(First embodiment)
FIG. 1 is a block diagram showing the configuration of the print inspection system 9. As illustrated in FIG. 1, the print inspection system 9 includes, for example, a DFE (Digital Front End) 1, an engine controller 2, a print engine 3, a print inspection apparatus 4 (an example of an inspection apparatus), and an information processing apparatus 5.

  The DFE 1 generates bitmap data (an example of an original image) to be printed based on the received print job, and outputs the generated bitmap data to the engine controller 2.

  The engine controller 2 controls the print engine 3 based on the bitmap data received from the DFE 1 to execute image formation output. Further, the engine controller 2 transmits the bitmap data received from the DFE 1 to the print inspection apparatus 4.

  The print engine 3 is an image forming apparatus that executes image formation output based on bitmap data under the control of the engine controller 2 to generate a printed matter.

  The print inspection apparatus 4 generates a master image (an example of a reference image) based on the bitmap data received from the engine controller 2 and compares it with a read image generated by electrically reading a printed matter generated by the print engine 3. The printed matter is inspected. Then, the print inspection apparatus 4 notifies the engine controller 2 of inspection results such as information indicating a defective printed material (for example, information indicating a page of the printed material). Thereby, the engine controller 2 can execute reprint control of a printed matter having a defect.

  The information processing apparatus 5 communicates with the engine controller 2 via a network such as a WAN (Wide Area Network). The information processing apparatus 5 is configured by a general information processing apparatus such as a PC (Personal Computer). The information processing apparatus 5 receives, for example, image information of a printed matter having a defect from the engine controller 2 according to the inspection result by the print inspection apparatus 4.

  FIG. 2 is a diagram illustrating a mechanical configuration of the print engine 3 and the print inspection apparatus 4. The print engine 3 has a configuration in which photosensitive drums 102Y, 102M, 102C, and 102K (hereinafter collectively referred to as photosensitive drums 102) of each color are arranged along a conveying belt 101 that is an endless moving unit. The so-called tandem type. That is, a plurality of photosensitive drums 102Y, 102M, 102C, and 102K are arranged along the transport belt 101 in order from the upstream side in the transport direction of the transport belt 101.

  Each color image developed with toner on the surface of each color photoconductive drum 102 is superimposed and transferred onto the conveyor belt 101 to form a full-color intermediate transfer image. The full-color intermediate transfer image formed on the transport belt 101 in this manner is moved from the paper feed tray 103 by the function of the transfer roller 104 at a position closest to the paper transport path indicated by the broken line in the drawing. Is transferred onto the surface of the paper that has been conveyed.

  The paper on which the image is formed on the paper surface is further transported, and after the image is fixed by the fixing roller 105, the paper is transported to the print inspection apparatus 4. In the case of duplex printing, the sheet on which an image is formed and fixed on one side is conveyed to the reversing path 106, reversed, and conveyed again to the transfer position of the transfer roller 104.

  The print engine 3 includes an operation display unit 302 that is a user interface (UI) of the print engine 3.

  Reading devices 401 a and 401 b provided on both sides of the sheet in the sheet conveyance path inside the print inspection apparatus 4 read the respective surfaces of the sheet conveyed from the print engine 3. The paper whose surface is read by the reading devices 401 a and 401 b is further conveyed inside the print inspection device 4, conveyed to the stacker 6, and discharged to the paper discharge tray 601.

  FIG. 3 is a block diagram illustrating a hardware configuration example of the print inspection apparatus 4. The print inspection apparatus 4 has the same configuration as an information processing apparatus such as a general PC or server. That is, the print inspection apparatus 4 includes a CPU (Central Processing Unit) 10, a RAM (Random Access Memory) 20, a ROM (Read Only Memory) 30, an HDD (Hard Disk Drive) 40, and an interface (I / F) 50. Connected through. In addition, a display unit 60, an operation unit 70, and a dedicated device 80 are connected to the I / F 50.

  The CPU 10 is a calculation means and controls the operation of the entire print inspection apparatus 4. The RAM 20 is a volatile storage medium capable of reading and writing information at high speed, and is used as a work area when the CPU 10 processes information. The ROM 30 is a read-only nonvolatile storage medium and stores a program such as firmware.

  The HDD 40 is a nonvolatile storage medium capable of reading and writing information, and stores an OS (Operating System), various control programs, application programs, and the like. The I / F 50 connects and controls the bus 90 and various hardware and networks.

  The display unit 60 is a visual user interface for the user to check the state of the print inspection apparatus 4 and is, for example, an LCD. The operation unit 70 is a user interface such as a keyboard and a mouse for the user to input information to the print inspection apparatus 4.

  The dedicated device 80 is hardware for realizing a dedicated function, and examples thereof include a dedicated arithmetic device and a scanner device for performing image processing at high speed such as an ASIC (Application Specific Integrated Circuit).

  In such a hardware configuration, a program stored in a recording medium such as the ROM 30, the HDD 40, or an optical disk is read out to the RAM 20, and the CPU 10 performs calculations according to those programs, thereby configuring a software control unit.

  The engine controller 2 and the print engine 3 can also employ the hardware configuration shown in FIG. In the case of the print engine 3, examples of the dedicated device 80 include a transport mechanism that transports paper and a plotter device. In the case of the engine controller 2, a dedicated arithmetic device for performing image processing at high speed, such as an ASIC, can be used.

  FIG. 4 is a block diagram illustrating a functional configuration example of the engine controller 2, the print engine 3, and the print inspection apparatus 4. In FIG. 4, data transmission / reception is indicated by a solid line, and the flow of paper is indicated by a broken line. Each function executed by the engine controller 2, the print engine 3, and the print inspection apparatus 4 may be configured by hardware or software.

  The engine controller 2 includes a data acquisition unit 201, an engine control unit 202, and a bitmap transmission unit 203. The print engine 3 includes a printing unit 301. The print inspection apparatus 4 includes a reading unit 401, a read image acquisition unit 402, a master image generation unit 403 (an example of a reference image generation unit), an inspection unit 404, a comparison unit 405, a display control unit 406, a reception unit 407, and a specification unit 408. And a change unit 409. Each function executed by the engine controller 2, the print engine 3, and the print inspection apparatus 4 may be configured by hardware or software.

  The data acquisition unit 201 acquires bitmap data input from the DFE 1 and operates the engine control unit 202 and the bitmap transmission unit 203, respectively. Bitmap data is information of each pixel constituting an image to be imaged and output. The engine control unit 202 causes the print engine 3 to execute image formation output based on the bitmap data transferred from the data acquisition unit 201. The bitmap transmission unit 203 transmits the bitmap data acquired by the data acquisition unit 201 to the print inspection apparatus 4 for generating a master image.

  The printing unit 301 acquires bitmap data input from the engine controller 2, executes image formation output based on the bitmap data on the paper, and generates a printed matter on which an image based on the bitmap data is formed. And output. The printing unit 301 can be realized by, for example, the photosensitive drum 102, the conveyance belt 101, the transfer roller 104, the fixing roller 105, and the like. The printing unit 301 is realized by a general electrophotographic image forming mechanism, but may have another image forming mechanism such as an ink jet method.

  The reading unit 401 reads the printed matter generated by the printing unit 301 to generate a read image and outputs it. The reading unit 401 can be realized by, for example, the reading devices 401 a and 401 b and the dedicated device 80.

  The read image acquisition unit 402 acquires a read image (an example of a first read image) obtained by reading a printed material. Specifically, the read image acquisition unit 402 acquires a read image of a printed matter from the reading unit 401 and outputs the acquired image to the inspection unit 404.

  The master image generation unit 403 generates a reference image based on the original image from which the printed material is generated. Specifically, the master image generation unit 403 receives bitmap data from the engine controller 2, and performs various kinds of processing such as multi-value conversion processing, smoothing processing, resolution conversion processing, and color conversion processing on the bitmap data. Image processing is performed to generate a master image.

  The inspection unit 404 includes threshold information composed of one or more types of thresholds, a difference image indicating a difference between the read image acquired by the read image acquisition unit 402 and the master image generated by the master image generation unit 403, The printed matter is inspected based on the above.

  Specifically, the inspection unit 404 outputs the read image acquired by the read image acquisition unit 402 and the master image generated by the master image generation unit 403 to the comparison unit 405. The comparison unit 405 compares the read image and the master image input from the inspection unit 404 for each corresponding pixel, and calculates a difference value of the pixel value for each pixel, so that a difference constituted by the difference value of each image An image is generated and output to the inspection unit 404. In the first embodiment, the read image and the master image are 200 dpi images represented by 8 bits for each color of RGB, but the present invention is not limited to this. In the first embodiment, the comparison unit 405 is configured by a dedicated device 80 such as an ASIC in order to quickly process an enormous amount of calculation, but is not limited thereto.

  The inspection unit 404 calculates, for each predetermined range, the total difference value of the pixels constituting the predetermined range for the difference image input from the comparison unit 405, and compares it with a threshold value for detecting a defect candidate region. If the total value is equal to or greater than the threshold value for detecting the defect candidate area, the predetermined range is set as the defect candidate area. The predetermined range is, for example, a range of several dots square to several tens dots square or hundreds of dots square.

  Here, the threshold information will be described. As one or more types of threshold values constituting the threshold information, for example, an area threshold value for determining whether or not the defect type is a defect for each type of defect may be used. However, the threshold value information is not limited to this. As the area threshold, for example, a point area threshold for determining whether or not an abnormal pixel group composed of abnormal pixels is a point-like defect, and for determining whether or not the abnormal pixel group is a horizontal line-like defect The horizontal line area threshold value for determining whether or not the abnormal pixel group is a vertical line defect is determined in order to determine whether or not it is the first density defect due to the high density of the abnormal pixel group. And a second density area threshold for determining whether or not the density defect is a second density defect due to a low density of the abnormal pixel group.

  In the first embodiment, one or more types of threshold values constituting the threshold information are a difference threshold value, a point area threshold value, a horizontal line area threshold value, a vertical value threshold for determining whether or not a pixel constituting the defect candidate region is an abnormal pixel. The case of the line area threshold, the first density area threshold, and the second density area threshold will be described as an example, but the present invention is not limited to this. However, in the first embodiment, since the difference threshold value is assumed to be fixed, the difference threshold value may not be included in the threshold information. In the first embodiment, the threshold information for detecting the defect candidate area is not included in the threshold information, but the threshold for detecting the defect candidate area may be included in the threshold information.

  The inspection unit 404 compares each pixel constituting the defect candidate area with a difference threshold value, and detects an abnormal pixel in the defect candidate area. Then, for each defect type, the inspection unit 404 counts the number of abnormal pixels constituting the abnormal pixel group that is a defect candidate of that type, and compares it with the area threshold value of the defect of that type. As a result, if the counted number of abnormal pixels is equal to or larger than the area threshold, the abnormal pixel group is determined as the type of defect, and the area on the read image corresponding to the defect candidate area is determined as the defective area.

  Thus, the inspection unit 404 inspects the presence or absence of defects on the printed matter by inspecting the presence or absence of defects on the difference image. Then, the inspection unit 404 transmits the inspection result to the engine controller 2.

  The display control unit 406 displays the inspection result of the inspection unit 404 on the display unit 60. Examples of the inspection result of the inspection unit 404 displayed on the display unit 60 include, but are not limited to, a thumbnail image of a read image and an enlarged image of a defective area on the read image. Note that the display control unit 406 may display the inspection result of the inspection unit 404 on the operation display unit 302.

  The accepting unit 407 accepts an input of an area on the printed matter in which there is a discrepancy between the inspection result of the inspecting unit 404 and the user's visual confirmation result (hereinafter may be referred to as “gap area”). Specifically, the user can obtain a gap region in which a gap is generated between the inspection result of the inspection unit 404 displayed on the display unit 60 and the confirmation result of the printed matter by his / her own visual inspection, that is, the inspection result of the inspection unit 404. Is a defective area but is a non-defective area in the visual confirmation result, or a non-defective area in the inspection result of the inspection unit 404 is a defective area in the visual confirmation result Check if there is any.

  When there is a gap area, the user performs a designation operation for designating the gap area on the enlarged image displayed on the display unit 60 from the operation unit 70, and the reception unit 407 receives an input of the designation operation. . Thereby, the accepting unit 407 accepts a designation operation for designating a gap area on the printed material.

  When the display control unit 406 displays the inspection result of the inspection unit 404 on the operation display unit 302, the user may perform a designation operation from the operation display unit 302.

  The specifying unit 408 specifies a region on the printed matter in which there is a contradiction between the inspection result of the inspection unit 404 and the result of visual confirmation by the user. Specifically, the specifying unit 408 specifies the gap region on the printed material by specifying the gap region specified by the specifying operation on the read image based on the specifying operation received by the receiving unit 407. .

  The changing unit 409 changes the threshold value information so as to eliminate the contradiction between the inspection result of the inspection unit 404 and the user's visual confirmation result generated in the region specified by the specifying unit 408. Specifically, when the inspection result of the inspection unit 404 indicates that the gap region specified by the specifying unit 408 is a defective region, the changing unit 409 sets threshold information so that the gap region becomes a non-defective region. To change. Similarly, when the inspection result of the inspection unit 404 indicates that the gap region specified by the specifying unit 408 is a non-defective region, the changing unit 409 changes the threshold information so that the gap region becomes a defective region. To do.

  Thereafter, the inspection unit 404 reinspects the printed matter based on the threshold information changed by the changing unit 409 and the difference image generated by the comparison unit 405. The re-inspection method for the printed matter is the same as the above-described inspection method except that the threshold information is changed.

  The display control unit 406 displays the re-inspection result of the inspection unit 404 on the display unit 60. The re-inspection result of the inspection unit 404 may be the same as the inspection result, or may be the content that is the same as the inspection result.

  Hereinafter, a specific operation of the print inspection apparatus 4 will be described.

  FIG. 5 is a flowchart illustrating a processing example of the print inspection apparatus 4.

  First, the read image acquisition unit 402 acquires a read image of a printed matter from the reading unit 401 (S501).

  Subsequently, the master image generation unit 403 generates a master image based on the original image from which the printed material is generated (S502).

  Subsequently, the inspection unit 404 outputs a printed matter based on the threshold information and a difference image that indicates a difference between the read image acquired by the read image acquisition unit 402 and the master image generated by the master image generation unit 403. Inspect (S503).

  Subsequently, the display control unit 406 displays the inspection result of the inspection unit 404 on the display unit 60 (S504).

  FIG. 6 is a diagram illustrating a screen example of the inspection result of the inspection unit 404. In the example illustrated in FIG. 6, the display control unit 406 first displays the job list screen 601 on the display unit 60 as the inspection result of the inspection unit 404. The job list screen 601 includes a job name, the number of defects detected in the job, a date and the like.

  When the user performs a selection operation for selecting a job from the operation unit 70 on the job list screen 601, and the reception unit 407 receives the selection operation, the display control unit 406 displays the page list screen 602 on the display unit 60. Let The page list screen 602 includes pages, thumbnail images, the number of detected defects, and the like.

  In the page list screen 602, when the user performs a selection operation for selecting a page from the operation unit 70 and the reception unit 407 receives the selection operation, the display control unit 406 displays the page screen 603 on the display unit 60. . The page screen 603 includes a thumbnail image 604 of a read image, an enlarged image 605 of a defective area on the read image, and the like. In the thumbnail image 604, a square indicating the range to be displayed in the enlarged image 605 is displayed so that the position of the enlarged image 605 can be seen. In the enlarged image 605, the defect area is indicated by a rectangle 606.

  Returning to FIG. 5, subsequently, the accepting unit 407 accepts an input of a designation operation for designating the gap area on the enlarged image displayed on the display unit 60 from the operation unit 70 (S505).

  FIG. 7 is an explanatory diagram of an example of a gap region designation method. When the user finds a gap region from the inspection result of the inspection unit 404 displayed on the display unit 60 and the confirmation result of the printed matter by his / her own visual inspection, the user selects the threshold value from the operation unit 70 on the page screen 603 described with reference to FIG. Press operation to press the setting button. When the accepting unit 407 accepts the pressing operation, the display control unit 406 switches the viewing mode page screen 603 to the threshold setting mode page screen 611 and causes the display unit 60 to display the page.

  In the enlarged image 612 of the page screen 611, a rectangle 613 and a rectangle 614 are displayed. A rectangle 613 is a rectangle that indicates a defective area, that is, an area that is determined as a defective area by the inspection result of the inspection unit 404. A rectangle 614 is a rectangle indicating a non-defective area, for example, an area that has been determined as a defect candidate area in the inspection result of the inspection unit 404 but has not been determined as a defect area. In the first embodiment, the rectangle 614 is not defined as a defective area in the inspection result of the inspection unit 404. However, when the inspection unit 404 inspects with other threshold information whose value is stricter than the threshold information described above, However, the present invention is not limited to this.

  On the page screen 611, a rectangle 613 and a rectangle 614 can be selected. For this reason, if the user determines that the region indicated by the rectangle 613 is a non-defective region and the region indicated by the rectangle 613 is a gap region as a result of visual confirmation, the rectangle 613 is set as a gap region from the operation unit 70. A designation operation for designation is performed, and the reception unit 407 receives the selection operation. Similarly, when the user determines that the area indicated by the rectangle 614 is a defect area and the area indicated by the rectangle 614 is a gap area as a result of visual confirmation, the user designates the rectangle 614 as a gap area from the operation unit 70. The designation operation is performed, and the receiving unit 407 receives the selection operation.

  Returning to FIG. 5, subsequently, the specifying unit 408 specifies the gap region specified by the specifying operation on the read image based on the specifying operation received by the receiving unit 407, so that the gap region on the printed material is determined. Is specified (S506).

  Subsequently, the changing unit 409 changes the threshold information so as to eliminate the gap generated in the gap region specified by the specifying unit 408 (S507).

  FIG. 8 is a chart illustrating threshold information held by the inspection unit 404. Since there are a plurality of types of threshold information held by the inspection unit 404, in the example shown in FIG. 8, it is assumed that these types of threshold information are represented in the threshold information table 801. The inspection unit 404 holds a threshold information table 801 on the storage area of the HDD 40. In the example illustrated in FIG. 8, threshold information for setting a and threshold information for setting b are registered in the threshold information table 801.

  As described above, the threshold information for setting a and the threshold information for setting b are each composed of a difference threshold, a point area threshold, a horizontal line area threshold, a vertical line area threshold, a first density area threshold, and a second density area threshold. ing. Each threshold value constituting the threshold information for setting b has a smaller value than the corresponding threshold value in the threshold information for setting a, and the threshold information for setting b is stricter than the threshold information for setting a. Yes. In the first embodiment, a case where the threshold information of setting a is threshold information used for inspection of a printed matter by the inspection unit 404 and the threshold information of setting b is the other threshold information described with reference to FIG. 7 will be described as an example. However, the present invention is not limited to this.

  In addition, the inspection unit 404 holds type determination threshold information for determining which type of defect candidate the abnormal pixel group in the defect candidate area is in the storage area of the HDD 40. FIG. 9 is a chart showing the type determination threshold information 802. In the example shown in FIG. 9, the threshold value that is the boundary between the point defect and the line defect is set to 2. In this case, if the result of dividing the length in the longitudinal direction of the abnormal pixel group by the length in the short direction of the abnormal pixel group is greater than 2, the abnormal pixel group becomes a defect candidate for a linear defect. If it is smaller, the abnormal pixel group becomes a defect candidate for a point defect. In the example shown in FIG. 9, the threshold value that is the boundary between the first density defect (dark portion) and the second density defect (thin portion) is 26.

  For example, in the abnormal pixel group 803 shown in FIG. 10 and the abnormal pixel group 804 shown in FIG. 11, the result of dividing the length in the longitudinal direction by the length in the short direction is larger than 2, so the abnormal pixel group 803 and The abnormal pixel group 804 is a defect candidate for a linear defect. The abnormal pixel group 803 is a vertical line defect candidate because the longitudinal direction is the vertical direction, and the abnormal pixel group 804 is a horizontal line defect candidate because the longitudinal direction is the horizontal direction. Further, for example, in the abnormal pixel group 805 shown in FIG. 12, the result of dividing the length in the longitudinal direction by the length in the short direction is smaller than 2, so the abnormal pixel group 805 is a defect candidate for a point defect. . 10 to 12, the vertical direction is the main scanning direction, and the horizontal direction is the sub-scanning direction.

  FIG. 13 is an explanatory diagram of an example of a changing method in the case where the threshold information is changed so as to become a non-defective region when the gap region is a defective region. In the case of the example illustrated in FIG. 13, the changing unit 409 compares each area threshold value configuring the threshold information of the setting a with the detection value detected by the inspection unit 404 corresponding to the area threshold value, and sets The threshold information of a is changed. The detection value detected by the inspection unit 404 through inspection is the number of abnormal pixels counted as described above.

  Specifically, as described above, the inspection unit 404 compares each pixel constituting the defect candidate area with the difference threshold value to detect abnormal pixels in the defect candidate area, and for each defect type, Since the number of abnormal pixels constituting the abnormal pixel group serving as a defect candidate is counted, the number of abnormal pixels counted for each type of defect becomes a detection value. The inspection unit 404 uses the type determination threshold information 802 to determine a type of defect candidate that can be an abnormal pixel group composed of abnormal pixels detected in the defect candidate area. For the type determined not to be obtained, the number of abnormal pixels counted is zero.

  Then, the changing unit 409 compares each area threshold value constituting the threshold information of the setting a with the detection value detected by the inspection unit 404 corresponding to the area threshold value, and if area threshold value> detection value, the area If the area threshold is equal to or smaller than the detection value without changing the threshold, the area threshold is changed to a value obtained by adding 1 to the detection value.

  In the case of the example shown in FIG. 13, since the detection value “20” corresponding to the vertical line area threshold is equal to or greater than the vertical line area threshold “10” (see reference numeral 901), the vertical line area threshold is set to “21 (20 + 1)”. Since the detection value corresponding to the first concentration area threshold is “30” is equal to or greater than the first concentration area threshold “10” (see reference numeral 903), the first concentration area threshold is set to “31 (see reference numeral 902). 30 + 1) "(see reference numeral 904). As a result, if the threshold information after the change is re-inspected, the area threshold value is greater than the detected value at any area threshold value, so the gap region is not a defective region but a non-defective region.

  FIG. 14 is an explanatory diagram of an example of a changing method in the case where the threshold information is changed so as to become a defective region when the gap region is a non-defective region. In the case of the example illustrated in FIG. 14, the changing unit 409 compares each area threshold value configuring the threshold value information of the setting b with the detection value detected by the inspection unit 404 corresponding to the area threshold value, and sets The threshold information of a is changed. The detection value detected by the inspection unit 404 through inspection is the number of abnormal pixels counted as described above.

  Specifically, the changing unit 409 compares each area threshold value configuring the threshold value information of the setting b with the detection value detected by the inspection unit 404 corresponding to the area threshold value, and the area threshold value ≧ the detected value. In this case, the area threshold value is not changed, and if the area threshold value <detection value, the area threshold value is changed to the detection value.

  In the case of the example shown in FIG. 14, since the detection value “5” corresponding to the vertical line area threshold exceeds the vertical line area threshold “2” of the setting b (see reference numeral 905), the vertical line area threshold of the setting a is The value is changed to “5” (see reference numeral 906), and the detection value corresponding to the first concentration area threshold value is “5” exceeds the first concentration area threshold value “2” of setting b (see reference numeral 907). The first density area threshold value of a is changed to “5” (see reference numeral 908). Thereby, if the threshold information of the setting a after the change is re-inspected, since the area threshold ≦ the detection value in the vertical line area threshold and the first concentration area threshold, the gap region is not a non-defective region but a defective region. Become.

  FIG. 15 is a flowchart illustrating a processing example of the print inspection apparatus 4 after the processing example described in FIG. In this flowchart, in S507 of the flowchart shown in FIG. 5, when the gap information is a defective area, the threshold information is changed so as to become a non-defective area.

  First, the inspection unit 404 reinspects the printed matter based on the threshold information changed by the changing unit 409 and the difference image generated by the comparison unit 405 (S601).

  Subsequently, the inspection unit 404 compares the inspection result of the printed matter with the re-inspection result. In addition to the gap region, the inspection result is a defective region in the inspection result, but is a region changed to a non-defective region in the re-inspection result. It is confirmed whether there is an affected area (S602).

  When there is an affected area (Yes in S602), the display control unit 406 displays information on the affected area on the display unit 60 as a re-inspection result of the inspecting unit 404 (S603).

  FIG. 16 is a diagram illustrating an example of a screen for information on the affected area. The affected area screen 1101 illustrated in FIG. 16 includes a thumbnail image including the affected area, a job name, a page number, and a check button 1102. The check button 1102 is provided with “defect” and “not defective”. By confirming the influence area screen 1101 shown in FIG. 16, the user can grasp the influence of the changed threshold information on areas other than the gap area.

  Returning to FIG. 15, the user then uses the operation unit 70 to perform an approval operation for selecting “not defective” on the check button 1102 if there is no problem with the affected area as a non-defective area for each affected area. . Thereby, the reception unit 407 receives an input of an approval operation from the operation unit 70 (S604).

  Subsequently, when the acceptance unit 407 receives an input of an approval operation, the inspection unit 404 updates the inspection result of the printed matter with the re-inspection result (S605). Thereby, the information on the defective area corresponding to the affected area is deleted from the inspection result of the printed matter.

  In S <b> 604, the user uses the operation unit 70 to perform a non-approval operation for selecting “defect” of the check button 1102 if there is a problem with the affected area as a non-defective area for each affected area. Thereby, the accepting unit 407 accepts an input of an unapproved operation from the operation unit 70 (S604). Note that the inspection unit 404 does not update the inspection result of the printed matter with the re-inspection result when the input of the non-approval operation is received by the reception unit 407.

  Note that this flowchart may be executed when the threshold information is changed to become a defective area in S507 of the flowchart shown in FIG. 5 when the gap area is a non-defective area. In this case, the affected area may be a non-defective area in the inspection result other than the gap area, but may be changed to a defective area in the re-inspection result.

  As described above, according to the first embodiment, the threshold value information is changed so as to eliminate the gap generated in the gap region. Therefore, the value can be easily changed to a value according to the user's intention. Further, according to the first embodiment, since the re-inspection result with the changed threshold information is displayed, the user can grasp the influence of the changed threshold information.

(Modification 1)
In the first embodiment, the user may be allowed to select whether to reflect the changed threshold information. In this case, the display control unit 406 displays a threshold information change confirmation screen 1201 shown in FIG. The threshold information change confirmation screen 1201 illustrated in FIG. 17 includes setting items (items for each threshold constituting the threshold information), the value of the setting a before the change, the value of the setting a after the change, and whether there is a change. Since a reflection button 1202 is displayed in the presence / absence of a change in the setting item whose value has been changed, the user performs a pressing operation of pressing the reflection button 1202 using the operation unit 70, whereby the reception unit 407 An input of a pressing operation is received from the operation unit 70, and the changing unit 409 confirms the change of the threshold information.

(Second Embodiment)
In the second embodiment, an example in which a gap region is automatically specified will be described. In the following, differences from the first embodiment will be mainly described, and components having the same functions as those in the first embodiment will be given the same names and symbols as those in the first embodiment, and the description thereof will be made. Omitted.

  FIG. 18 is a block diagram illustrating a functional configuration example of the engine controller 2, the print engine 3, and the print inspection apparatus 2004 in the print inspection system 2009. As shown in FIG. 18, a reading unit 2401, a read image acquisition unit 2402, a specifying unit 2408, and a changing unit 2409 are different from the first embodiment.

  The reading unit 2401 generates a read image by reading a printed matter generated by the printing unit 301 and in which a region in which a contradiction occurs between the inspection result of the inspection unit 404 and the user's visual confirmation result is designated by the user. ,Output.

  The read image acquisition unit 2402 reads a read image (an example of a second read image) obtained by reading a printed matter in which a region in which a contradiction occurs between the inspection result of the inspection unit 404 and the result of visual confirmation by the user. Hereinafter referred to as “designated read image”). Specifically, the read image acquisition unit 2402 acquires a designated read image of a printed matter from the reading unit 2401 and outputs the acquired read image to the specifying unit 2408.

  For example, when the reception unit 407 receives an operation for setting the threshold setting mode from the operation unit 70 and the print inspection apparatus 2004 is in the threshold setting mode, the inspection result of the inspection unit 404 and the user's visual confirmation result The reading unit 2401 reads the printed matter designated by the user in the area where the contradiction occurs. When the print inspection apparatus 2004 is in the threshold setting mode, the read image acquisition unit 2402 can output the designated read image to the specifying unit 2408 instead of the inspection unit 404 by outputting the read image to the specifying unit 2408.

  Based on the designated read image acquired by the read image acquisition unit 2402, the specifying unit 2408 specifies a region in which there is a contradiction between the inspection result of the inspection unit 404 and the result of visual confirmation by the user.

  A gap region, which is a region in which there is a discrepancy between the inspection result of the inspection unit 404 and the user's visual confirmation result, is designated by a symbol attached to the printed matter. Then, the specifying unit 2408 detects the symbol on the designated read image, and specifies the gap region based on the symbol. Note that the specifying unit 2408 specifies the gap region by a specifying method according to the detected symbol type.

  The changing unit 2409 changes the threshold information based on the symbol attribute detected by the specifying unit 2408 so as to eliminate the contradiction between the inspection result of the inspection unit 404 and the user's visual confirmation result in the gap region. To do.

  Hereinafter, a specific method for specifying the gap region will be described.

  First, a description will be given of a specific method in the case where a symbol is a pen mark.

  FIG. 19 is an explanatory diagram of a method for designating a gap region on a printed material by a user giving a mark with a pen. The user finds the gap area on the printed material (1301), and uses the pen 2002 to mark the gap area (1302). Here, an example is shown in which, for example, two gap regions on a printed material are surrounded by a colored pen 2002 such as blue. Then, the reading unit 2401 reads the printed matter with the symbol attached thereto to generate three RGB RGB bitmap data (1303), and the read image acquisition unit 2402 acquires it.

  FIG. 20 is an explanatory diagram of a method for identifying a gap region when a symbol is a mark with a pen. FIG. 21 is a flowchart showing the gap area specifying process when the symbol is a pen mark.

  In step 1300 (S1300), the specifying unit 2408 receives three RGB bitmap data (hereinafter referred to as “RGB data 1303”) from the read image acquisition unit 2402.

  In step 1302 (S1302), the specifying unit 2408 subtracts the background color data of the printed matter (specifically, the background color data of the printed matter paper) from the RGB data 1303 to remove the influence of the background color. Note that the background color data of the printed matter is managed by the engine controller 2 or the like as paper information, for example.

  In step 1304 (S1304), the specifying unit 2408 compares the RGB data 1303 with the RGB values of the pen 2002 registered in the preset RGB data table 1401 of the pen. The specifying unit 2408 sets a flag for a pixel that approximates the R value of the pen 2002 in the R data of the RGB data 1303, and flags a pixel that approximates the G value of the pen 2002 in the G data of the RGB data 1303. In the B data of the RGB data 1303, the RGB data 1402 is generated by setting a flag on the pixel that approximates the B value of the pen 2002.

  FIG. 22 is a chart illustrating the RGB data table 1401. As shown in FIG. 22, the RGB data table 1401 shows the pen unique ID, the pen RGB value, and the attribute. Here, the attribute is a threshold value to be changed (for example, a point area threshold value, a horizontal line area threshold value, a vertical line area threshold value, a first density area threshold value, and a second density threshold value) if the threshold value to be changed is changed depending on the pen type. One of the density area threshold values). For example, if it is desired to specify a user whose threshold information has been changed according to the type of pen, the attribute indicates a user who uses the pen (the owner of the pen).

  Note that when the user uses a plurality of types of pens registered in the RGB data table 1401 to give a mark, the specifying unit 2408 generates RGB data 1402 for each used pen.

  In step 1306 (S1306), the specifying unit 2408 specifies a pixel that is flagged in all of the R data, the G data, and the B data of the RGB data 1402, and sets a region surrounded by the pixel as a gap on the printed matter. The area is confirmed (1403).

  In step 1308 (S1308), the identifying unit 2408 generates a gap area list 1404 of the confirmed gap areas.

  FIG. 23 is a chart showing a specific example of the gap area list 1404. As shown in FIG. 23, the gap region list 1404 shows attributes and X and Y coordinates from the reference points of the top, bottom, rightmost, and leftmost portions of the mark. The reference point is a position held by the print inspection apparatus 2004.

  Then, the specifying unit 2408 specifies the position of each gap region 1405 on the RGB data 1303 from the gap region list 1404, and the changing unit 2409 is based on the sign attribute detected by the specifying unit 2408. The threshold information is changed so as to eliminate the gap.

  For example, if the attribute indicates a threshold value to be changed, the changing unit 2409 changes the threshold value to be changed indicated by the attribute, and if the attribute indicates a user who uses a pen, the user indicated by the attribute is changed to the threshold value. Keep a history of information changers.

  Next, a description will be given of a specific method in the case where the symbol is a mark with a sticky note.

  FIG. 24 is an explanatory diagram of a method for specifying a gap region when a symbol is a mark by a sticky note.

  The user finds a gap area on the printed matter and uses the tag 2000 to mark the vicinity of the gap area (1501).

  Subsequently, the identifying unit 2408 refers to the RGB data of the tag 2000 and identifies the position of the mark (1503). The position of the mark can be specified by a method similar to that in the case where the symbol is a pen mark. However, instead of the RGB data table 1401, a preset RGB data table 1502 of sticky notes is used.

  When the symbol is a mark with a sticky note, the gap region cannot be specified only by specifying the position of the mark, unlike the case where the symbol is a mark with a pen. Therefore, for example, the specifying unit 2408 gradually increases the circle around the reference point of the sticky note, and when the circle touches the abnormal pixel, the point where the circle is to be reflected around the touched point is interrupted (the circle is abnormal). The gap region 1506 is identified by spreading (until the pixel is no longer touched) (1504). Further, for example, the specifying unit 2408 gradually increases the circle around the reference point of the sticky note, and spreads it until the portion to be reflected is interrupted after the circle touches the abnormal pixel (until the circle stops touching the abnormal pixel). (1505), the gap region 1506 is specified. In any of the examples, the reference point of the sticky note is fixed at the left center of the sticky note, but is not limited to this.

  Next, a description will be given of a specific method when the symbol is a sticky note and a mark with a pen. This is to prevent the specified gap area from being outside the printed matter area when a part of the sticky note protrudes from the paper when only the sticky note is included.

  FIG. 25 is an explanatory diagram of a method for specifying a gap region when a symbol is a sticky note and a mark using a pen.

  The user finds the gap area on the printed matter, uses the sticky note 2000 to mark the vicinity of the gap area, and marks the corner of the sticky note 2000 close to the gap area with the pen 2002 (1601).

  Subsequently, the position of the mark with the sticky note can be specified by the same method as the case of the mark with the sticky note, and the position of the mark with the pen can be specified by the same method as the case of the mark with the pen. Can be identified. Then, the specifying unit 2408 specifies the gap region by the above-described method using, for example, the corner of the sticky note 2000 that is close to a mark with a pen as a reference point (1602).

1 DFE
2 Engine controller 3 Print engine 4, 2004 Print inspection device 5 Information processing device 9, 2009 Print inspection system 60 Display unit 70 Operation unit 401, 2401 Reading unit 402, 2402 Read image acquisition unit 403 Master image generation unit 404 Inspection unit 405 Comparison Unit 406 display control unit 407 reception unit 408, 2408 identification unit 409, 2409 change unit

Japanese Patent No. 4677718

Claims (11)

A read image acquisition unit that acquires a first read image obtained by reading a printed matter;
A reference image generation unit that generates a reference image based on the original image from which the printed material is generated;
An inspection unit that inspects the printed matter based on threshold information composed of one or more types of thresholds and a difference image indicating a difference between the first read image and the reference image;
A specifying unit for specifying an area on the printed matter in which a contradiction occurs between an inspection result and a user's visual confirmation result;
A changing unit for changing the threshold information so as to eliminate the contradiction in the region;
An inspection apparatus comprising: A reception unit that receives a specifying operation for specifying the area;
The inspection apparatus according to claim 1, wherein the specifying unit specifies the region based on the designation operation. The read image acquisition unit further acquires a second read image obtained by reading the printed matter in which the region is specified,
The inspection apparatus according to claim 1, wherein the specifying unit specifies the region based on the second read image. The area is specified by a symbol attached to the printed matter,
The inspection apparatus according to claim 3, wherein the specifying unit detects the symbol on the second read image and specifies the region based on the symbol.   The inspection device according to claim 4, wherein the specifying unit specifies the region by a specifying method according to a type of the symbol.   The inspection apparatus according to claim 4 or 5, wherein the changing unit changes the threshold information so as to eliminate the contradiction of the inspection result in the region based on the attribute of the symbol.   The said change part changes the said threshold value information so that the said area | region may become a non-defect area | region, when the said test result shows that the said area | region is a defect area | region. Inspection device.   The said change part changes the said threshold value information so that the said area | region may become a defect area | region, when the said test result shows that the said area | region is a non-defect area | region. Inspection device. The inspection unit re-inspects the printed matter based on the changed threshold information and the difference image,
The inspection apparatus according to claim 1, further comprising a display control unit that displays a reinspection result on the display unit. A read image acquisition step of acquiring a read image obtained by reading a printed matter;
A reference image generating step for generating a reference image based on the original image from which the printed matter is generated;
An inspection step of inspecting the printed matter based on threshold information composed of one or more thresholds and a difference image indicating a difference between the read image and the reference image;
A specific step of identifying an area on the printed matter in which there is a discrepancy between the inspection result and the visual confirmation result of the user;
Changing the threshold information to resolve the contradiction in the region;
Threshold change method including: A read image acquisition step of acquiring a first read image obtained by reading a printed matter;
A reference image generating step for generating a reference image based on the original image from which the printed matter is generated;
An inspection step of inspecting the printed matter based on threshold information composed of one or more thresholds and a difference image indicating a difference between the first read image and the reference image;
A specific step of identifying an area on the printed matter in which there is a discrepancy between the inspection result and the visual confirmation result of the user;
Changing the threshold information to resolve the contradiction in the region;
A program that causes a computer to execute.

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