JP2020024110A - Inspection device and inspection method - Google Patents

Abstract

To allow for inspecting prints more easily.SOLUTION: An inspection device provided herein is for inspecting prints printed by a digital printer. The inspection device comprises an image capturing unit configured to capture an image of a print and output captured image data, and a processing unit configured to perform an inspection process for the print using printed image data generated according to a print instruction received by the printer and the captured image data. The processing unit is configured to generate first labeling data by applying a coupled component labeling process to the printed image data, generate second labeling data by applying the coupled component labeling process to the captured image data, inspect the print by comparing the first labeling data and the second labeling data, and output an inspection result.SELECTED DRAWING: Figure 3

Description

  The present disclosure relates to an apparatus and a method for inspecting printed matter.

  Patent Document 1 discloses an apparatus for inspecting a printed matter printed by a digital printing machine. The apparatus performs an inspection based on a difference between a master image generated from print data and a read image generated by reading a printed material with a reading device. It describes that by generating a master image from print data, it is possible to efficiently inspect printed matter by, for example, variable printing (Variable Data Printing: VDP).

JP 2015-174307 A

  According to the conventional inspection method disclosed in Patent Document 1, it is possible to inspect a printed matter with high accuracy. However, since a high information processing capability is required for matching the master image with the read image, a large-scale and expensive inspection device is required.

  The present disclosure provides an inspection method capable of inspecting a printed material with a relatively small configuration.

  An inspection device according to an embodiment of the present disclosure inspects a printed matter printed by a printing machine that performs digital printing. The inspection device is an imaging device that captures the printed matter and outputs captured image data, and a print image data generated based on a print instruction input to the printing press and the printed matter based on the captured image data. A processing device for performing an inspection process. The processing device generates first labeling data by performing connected component labeling processing on the print image data, and generates second labeling data by performing connected component labeling processing on the captured image data. The printed matter is inspected by comparing labeling data with the second labeling data, and an inspection result is output.

  General or specific aspects of the present disclosure can be realized by an apparatus, a system, a method, an integrated circuit, a computer program, or a recording medium. Alternatively, the present invention may be realized by any combination of an apparatus, a system, a method, an integrated circuit, a computer program, and a recording medium.

  According to the embodiments of the present disclosure, it is possible to inspect a printed material with a simpler configuration than before.

FIG. 1 is a diagram schematically illustrating an outline of a configuration of a print inspection system according to a first exemplary embodiment of the present disclosure. FIG. 2 is a diagram for explaining functions of the processing device 210. FIG. 3 is a flowchart illustrating a process executed by the processor 212 of the processing device 210. FIG. 4A is a diagram illustrating an example of an image before labeling. FIG. 4B is a diagram illustrating an example of an image after labeling. FIG. 5 is a diagram illustrating an example of labeling data corresponding to the labeling result illustrated in FIG. 4B. FIG. 6A is a diagram illustrating an example of the first labeling data. FIG. 6B is a diagram illustrating an example of the second labeling data. FIG. 7 is a diagram illustrating a functional configuration of a print inspection system according to the second exemplary embodiment of the present disclosure. FIG. 8 is a diagram schematically illustrating an example of an image of one page to be printed. FIG. 9 is a diagram illustrating an example of the print schedule list. FIG. 10 is a flowchart illustrating processing executed by the processor 212 according to the second embodiment. FIG. 11 is a flowchart illustrating a process of the processor 212 according to the modification of the second embodiment.

(Knowledge underlying the present disclosure)
Before describing the embodiments of the present disclosure, the knowledge that became the basis of the present disclosure will be described.

  A digital printer that performs variable printing (hereinafter also referred to as “variable printing”) prints different contents for each page. For this reason, such printing machines are widely used for various purposes such as address printing, bill printing, and statement printing.

  In variable printing, since different contents are printed for each page, inspection cannot be performed by a simple method such as comparing with a single image prepared in advance. For this reason, a method is conceivable in which an inspection is performed by comparing and collating image data serving as a printing source with image data obtained by capturing an image of a printed material. For example, Patent Document 1 mentioned above discloses an example of such a method.

However, in the method of comparing two images, a high information processing capability is required for the inspection apparatus for the following reasons.
With the recent increase in resolution and printing speed of printing presses and imaging devices, it is necessary to process a large amount of image data in a short time.
-The image developed in the printing press does not always match the image developed in the inspection device, and a difference may occur.
Differences occur between an image to be printed and an actually printed image due to characteristics such as paper or ink.
-For matching, strict alignment is required between the master image and the read image, and a high precision is required for the transport mechanism.

  For these reasons, the conventional method has a problem that a large-scale and expensive inspection device is required.

  The inspection apparatus of the conventional print data collation method can improve the accuracy of the inspection, and thus is suitable for printed matter requiring high quality. However, there are many cases where the accuracy is excessive for general printed matter, and the application scene is limited. Further, in order to apply the present invention to a variable printing machine that performs printing while conveying a sheet at a high speed, an arithmetic unit having a high processing capability is required, which leads to an increase in cost.

  The present inventor has found the above problems in the related art, and has arrived at a configuration of an embodiment of the present disclosure described below. Hereinafter, an outline of an embodiment of the present disclosure will be described.

  An inspection apparatus according to an exemplary embodiment of the present disclosure inspects printed matter printed by a printing machine that performs digital printing. The inspection device includes an imaging device and a processing device. The imaging device captures an image of a printed matter printed by a printing machine and outputs captured image data. The processing device performs a print inspection process based on print image data generated based on a print instruction input to the printing press and captured image data. The processing apparatus generates first labeling data by performing connected component labeling processing on the print image data, and generates second labeling data by performing connected component labeling processing on the captured image data. Then, the printed matter is inspected by comparing the first labeling data with the second labeling data.

  With such a configuration, the load of the inspection process can be greatly reduced as compared with the conventional method of directly detecting the print image data and the captured image data to detect a defect. As a result, the inspection can be realized with a smaller and lower-cost device.

  Here, the “connected component labeling process” refers to a process of assigning the same label (for example, number) to pixels constituting the same connected component in an image and assigning different labels to pixels constituting different connected components. The “connected component labeling process” may be simply referred to as “labeling”.

  The first labeling data may include, for example, at least one piece of information about the number of connected components included in the print image data, the size of each connected component, and the position of each connected component. Similarly, the second labeling data may include, for example, at least one piece of information on the number of connected components included in the captured image data, the size of each connected component, and the position of each connected component. The “size” of the connected component refers to the number of pixels constituting the connected component (hereinafter also referred to as “area”) or the size (dimension) in the horizontal or vertical direction occupied by the area of the pixels constituting the connected component ).

  The processing device compares the number of connected components, the size of each connected component, and at least one of the positions of each connected component between the print image data and the captured image data, for example, to detect a defect in the printed matter. Can be detected.

  The data size of the first labeling data is smaller than the data size of the print image data. For example, the data size of the first labeling data is smaller than 1/10 of the data size of the print image data. In one example, the data size of the first labeling data is smaller than 1/100 of the data size of the print image data. Similarly, the data size of the second labeling data is smaller than the data size of the captured image data. For example, the data size of the second labeling data is smaller than 1/10 of the data size of the captured image data. In one example, the data size of the second labeling data is smaller than 1/100 of the data size of the captured image data.

  Assuming that the print image data and the captured image data are, for example, image data of tens of thousands to millions of pixels, their data size is, for example, several kilobytes to several megabytes. On the other hand, even if each labeling data includes all information on the area, the size in the X direction, the size in the Y direction, and the position of each connected component, and the number of connected components, the data size is less than 100 bytes. Therefore, the process of comparing the two labeling data can be executed with a much smaller amount of calculation than the process of comparing the print image data and the captured image data.

  The printing press may be, for example, a printing press that performs variable printing on the conveyed paper or film. The imaging device may include a linear image sensor (also referred to as a line sensor) that images the transported printed paper or film line by line. The imaging device is controlled to output captured image data for each page. The processing device performs an inspection based on a comparison between the first labeling data and the second labeling data for each page of the printed matter.

  According to the embodiment of the present disclosure, a check can be performed with a small amount of calculation. For this reason, even when a processor having a low computing capacity is used, the inspection can be executed by following the variable printing speed. In other words, the inspection can be performed with a smaller and lower-cost device than before. The technology of the present disclosure can be applied to general digital printing other than variable printing.

  An inspection apparatus according to another exemplary embodiment of the present disclosure inspects a printed matter printed by a printing machine that performs digital printing. An inspection device configured to image the printed matter and output captured image data; an inspection apparatus configured to inspect the printed matter based on the print image data generated based on a print instruction input to a printing machine and the captured image data And a processing device for performing processing. The processing device recognizes page information for specifying the page of the printed matter from the print image data, and generates an inspection result list in which the association between the page information and the inspection result is recorded.

  According to the above aspect, the page information is recognized from the print image data, and the inspection result list is generated based on the information. For this reason, it is possible to more appropriately manage the print inspection result than before.

  The page information may be characters (for example, numbers or alphabets) indicating the page. The processing device may recognize the page information by, for example, character recognition.

  The processing device may further recognize other page information for specifying the page of the printed matter from the captured image data. The processing device may output the inspection result list including information indicating whether the page information matches the other page information.

  The printing press may be a printing press that performs variable printing on the conveyed paper. In that case, the imaging device outputs the captured image data for each page. The processing device generates an inspection result list for each page.

  Hereinafter, embodiments of the present disclosure will be described in more detail. However, an unnecessary detailed description may be omitted. For example, a detailed description of a well-known item or a redundant description of substantially the same configuration may be omitted. This is to prevent the following description from being unnecessarily redundant and to facilitate understanding of those skilled in the art. The inventor provides the accompanying drawings and the following description so that those skilled in the art can fully understand the present disclosure, and these are not intended to limit the subject matter described in the claims. Absent. In this specification, the same or similar components have the same reference characters allotted.

(Embodiment 1)
FIG. 1 is a diagram schematically illustrating an outline of a configuration of a print inspection system according to a first exemplary embodiment of the present disclosure. This print inspection system includes a printing machine 100 and an inspection device 200. FIG. 1 also shows a computer 300 connected to the printing press 100 and the inspection device 200. The computer 300 may be a general-purpose information processing device such as a server computer, a personal computer (PC), or a mobile terminal. The computer 300 may be included in the print inspection system, or may be an external element of the print inspection system.

  The printing press 100 includes a controller 110, a print head 120, and a transport device 130. The transporter 130 transports the rolled paper 10. The controller 110 is a circuit that controls the entire operation of the printing press 100. The controller 110 drives the transport device 130 and the print head 120 in response to a print instruction input from the computer 300. Thus, the printing press 100 executes printing while transporting the paper 10.

  The printing press 100 according to the present embodiment has a function of performing variable printing. That is, characters, graphics, images, or the like that are different for each page are continuously printed on the paper 10. The paper 10 in the present embodiment is a roll paper, but may be printed on another print medium such as a film.

  The inspection device 200 operates in conjunction with the printing press 100 to inspect the printed paper 10. The inspection device 200 is connected to the printing press 100 and the computer 300. The inspection device 200 includes an imaging device 220 and a processing device 210.

  The imaging device 220 is arranged on the transport path of the printed sheet 10. The imaging device 220 captures an image of the paper 10 after printing, and outputs captured image data for each page. The imaging device 220 includes an image sensor such as a CCD or a CMOS. The imaging device 220 is not limited to a two-dimensional image sensor, and may include a linear image sensor. In that case, the image capturing device 220 captures the image of the conveyed sheet 10 line by line, and collects data of a plurality of lines for each page and outputs the data as captured image data.

  The processing device 210 includes a processor 212, a storage medium such as a RAM 214 and a ROM 216, and an input / output interface (IF) 218. The processor 212 includes an arithmetic circuit such as a CPU or a GPU. ROM 216 stores computer programs executed by processor 212. The program includes, for example, an instruction group for causing the processor 212 to execute a process illustrated by a flowchart described below or a part thereof. The RAM 214 is a work memory for expanding the program when the processor 212 executes the program. The processor 212 of the processing device 210 is connected to the computer 300, the controller 110, and the imaging device 220 via the interface 218.

  The processing device 210 acquires print image data from the controller 110. The processing device 210 also acquires captured image data from the imaging device 220. The print image data is data of a two-dimensional image generated by the controller 110 in accordance with an instruction from the computer 300. The captured image data is data of a two-dimensional image generated by the imaging device 220 capturing a printed matter. These two-dimensional images may be any of a color image, a grayscale image, and a black and white binary image. The number of pixels may be different between the image output by the controller 110 and the image output by the imaging device 220. The processor 212 may perform necessary processing such as binarization by adjusting the number of pixels of both images, and then perform processing described later.

  The processing device 210 acquires a print schedule list from the computer 300, adds the inspection result to the list, and outputs the list. The print schedule list may be provided in a format such as a CSV file.

FIG. 2 is a diagram for explaining functions of the processing device 210. As illustrated, the processing device 210 in the present embodiment performs the following processing.
・ Printed image labeling ・ Captured image labeling ・ Labeling result collation ・ Print schedule list acquisition ・ Inspection result addition ・ Inspection result list output

  Hereinafter, these processes will be described.

  FIG. 3 is a flowchart illustrating a process executed by the processor 212 of the processing device 210. After the start of printing, the processor 212 repeats the processing of steps S101 to S106 for each page of the printed matter until receiving a print end instruction (step S107) from the controller 110.

  In step S101, the processor 212 acquires print image data from the controller 110. In step S102, the processor 212 acquires captured image data from the imaging device 220. The order of step S101 and step S102 may be reversed or may be simultaneous.

  In step S103, the processor 212 performs a connected component labeling process on the print image data to generate first labeling data. In step S104, the processor 212 performs a connected component labeling process on the captured image data to generate second labeling data. The order of step S103 and step S103 may be reversed or may be simultaneous.

  In step S105, the processor 212 performs an inspection by comparing the first labeling data with the second labeling data. That is, the inspection is performed by collating the labeling results obtained from each of the print data and the photographing data. In step S106, the processor 212 adds the information of the comparison result to the print schedule list. In step S107, the processor 212 determines whether or not there is an instruction to end printing, and if there is no instruction to end printing, returns to step S101 and checks the next page.

  FIGS. 4A and 4B are diagrams for explaining the labeling processing in steps S103 and S104. FIG. 4A shows an example of an image before labeling. FIG. 4B shows an example of an image after labeling. 4A and 4B show an example of an image having a smaller number of pixels than an actual image for convenience of description. An actual image may have, for example, tens of thousands to millions of pixels.

  The processor 212 in this embodiment converts each of the print image data and the captured image data into a monochrome binary bitmap image of the same size, and then performs a labeling process. As is well known, labeling is a process in which continuous white or black regions (connected components) in an image are regarded as one group, and different labels (for example, numbers) are assigned to the respective connected components. In the example shown in FIG. 4B, four separated white areas are numbered from 1 to 4.

  As a labeling algorithm, for example, a known method such as a method based on a raster scan using a lookup table or a method based on contour tracing can be adopted. The connected component may be defined by four connections or eight connections.

  The labeling data represents the characteristics of each connected component. For example, features such as the area of each connected component, the size in the X direction, the size in the Y direction, and the position are represented.

  FIG. 5 shows an example of labeling data corresponding to the labeling result shown in FIG. 4B. The labeling data in this example is a table including information on the label (number), position, area, X-direction size, and Y-direction size of each connected component. “Position” in the example of FIG. 5 represents the coordinates of the center of gravity of the pixels constituting the connected component. In this example, the X-axis is set in the right direction and the Y-axis is set in the lower direction with the upper left end of the image as the origin, but the coordinates may be taken in any manner. “Area” is the number of pixels constituting the connected component. “X direction size” is the maximum value of the number of pixels that are continuous in the X direction in the connected component. “Y direction size” is the maximum value of the number of pixels that are continuous in the Y direction in the connected component. The labeling data is not limited to the data as shown in FIG. 5, but may be any data that indicates the characteristics of each connected component. For example, the perimeter of each connected component may be included in the labeling data.

  Labeling data can represent image features with a significantly smaller amount of information than the original bitmap image. For example, a feature of an image can be represented by an information amount of several bytes to several tens bytes. For this reason, when the collation between the labeling data is performed, the inspection processing can be sped up as compared with the case where the collation between the images is performed. If different characters are printed on each page, such as a destination name, bill, or statement of usage, full collation may not be possible on a character-by-character basis, but page misalignment may be based on the number of characters or the approximate size of the characters. Can often be detected. Generally, a page shift of a sheet does not occur only on one page, but is continuous. Therefore, it can be detected in most cases by the method of the present embodiment. When kanji is used, the number of knits and structures can be collated by labeling, so that collation can be performed with high accuracy. Even when dirt adheres, it is often detectable due to the mismatch in the number of labels. In addition, when there is a missing print, if there is an abnormality in the number of labels, it can be easily detected. Many defects can be detected only by comparing the number of labels.

  6A and 6B are diagrams illustrating an example in which a difference occurs between the first labeling data and the second labeling data. FIG. 6A shows an example of the first labeling data. FIG. 6B shows an example of the second labeling data. In this example, in the actually printed image, the white area in the upper left (the connected component to which the label “1” is added) is enlarged as compared with the image to be printed. As a result, the “position”, “area”, and “Y size” of the connected component of the label “1” are different between the first labeling data and the second labeling data. If the difference between any of these values is greater than a preset threshold, the processor 212 determines that a print defect has occurred and writes information to that effect to the print schedule list. In this case, the processor 212 may transmit a signal requesting reprinting of the page to the controller 110 of the printing press 100. When the printing machine 100 receives the signal, it reprints the page.

  As described above, the inspection device 200 of the present embodiment performs an inspection based on the data of the image to be printed acquired from the controller 110 of the printing press 100 and the data of the printed image acquired from the imaging device 220. . By performing the labeling process on each of the data of the image to be printed and the data of the actually printed image, the amount of data to be processed can be significantly reduced.

  In recent years, printing machines and cameras (imaging devices) have been increased in resolution and printing speed, and the need to handle large volumes of data at high speed has increased. For this reason, the conventional method of acquiring the difference between the image data of the printing source and the image data obtained by imaging the printed matter and performing the comparison inspection requires a large-scale and high-cost apparatus. According to the present embodiment, since the data amount can be significantly reduced at the initial stage of the inspection, the inspection can be realized with a smaller and lower-cost device.

  Further, according to the method of the present embodiment, the flexibility of inspection can be increased. Normally, the data to be printed and the data obtained by reading the printed data do not completely match. Both images are different due to the influence of paper bleeding or expansion and contraction of the paper. In the method of Patent Literature 1, an inspection allowable value is set by adjusting a threshold value and an area of difference data between two images. If the overall allowable range of the coordinate shift is increased, there are many trade-off factors, such as difficulty in detecting dirt around the character, and the setting and adjustment become complicated.

  In the labeling inspection according to the present embodiment, the size, area, coordinates, and the like of each print object (for example, characters, symbols, or barcodes) can be compared, so that more flexible settings can be made. For example, it is easy to set according to the required print quality, for example, by setting the allowable value of the difference between the areas of the objects (dirt or shading) to be strict while setting the allowable value of the overall coordinate shift large.

(Embodiment 2)
Next, a second embodiment of the present disclosure will be described.

  FIG. 7 is a diagram illustrating a functional configuration of the print inspection system according to the present embodiment. In the present embodiment, only the operation of the processing device 210 is different from that of the first embodiment. The processing device 210 according to the present embodiment recognizes information for specifying a page from print image data, and performs print management based on the information, in addition to the operation of the first embodiment. Hereinafter, points different from the first embodiment will be described, and redundant description will be omitted.

  The print image data in the present embodiment includes information for specifying a page such as a page number and a serial number. For example, in variable printing such as address printing and slip printing, print-specific image data often includes page-specific information (for example, a page number or a serial number) in order to respond to inquiries after shipment and for traceability. By recognizing such page-specific information from the image data, it is possible to efficiently perform inspection management for each page and total inspection results.

  As illustrated in FIG. 7, the processing device 210 according to the present embodiment recognizes a page number included in the print image data acquired from the controller 110 using a character recognition technology. Similarly, the processor 212 recognizes the page number included in the captured image data output from the imaging device 220 by using the character recognition technology. For character recognition, for example, a known OCR technique or the like can be used. The processor 212 generates and outputs a test result list including test result information for each page based on the recognized page number information and the print schedule list.

  FIG. 8 is a diagram schematically illustrating an example of an image of one page to be printed. In this example, a form including the address is printed. This form includes a number 410 for identifying a page, a bar code 430, and a two-dimensional code 440. The number 410, the barcode 430, the two-dimensional code 440, and the address portion surrounded by a thick frame differ depending on the page, and the other portions are common regardless of the page. When printing such a form, the processor 212 can identify the page by recognizing the number 410. The processor 212 may specify a page by reading a barcode 430 or a two-dimensional code 440 (for example, a QR code (registered trademark)) instead of character recognition.

  FIG. 9 is a diagram illustrating an example of the print schedule list. The print schedule list in this example includes an inspection schedule number, information indicating whether or not printing has been performed, information indicating a label collation result, information indicating a character recognition result, information indicating a character collation result, and an inspection result. And information indicating the total result of the inspection. The inspection schedule number is a number corresponding to the page number, and is included in the print schedule list from the beginning. The information indicating whether or not printing has been completed indicates whether or not printing of the page has been completed. The label collation result indicates whether or not the above-described labeling processing has been completed without any problem. The character recognition result indicates a number for identifying the page recognized from the print image data. The character collation result indicates whether the recognized number matches the inspection schedule number, and if they match, the result is OK. The information indicating the test result indicates whether the test has been completed normally. The overall result of the inspection is OK if all of the label collation, character collation, and inspection are OK. The processor 212 performs character recognition such as a page number, character collation, and inspection every time one page is completed, and records the result in a list as shown in FIG. Since the result of the character recognition and the result of the inspection are recorded as the printing progresses, a useful inspection record can be generated. Note that the list shown in FIG. 9 is merely an example. The generated print result list may include information not shown in FIG. 9 or may not include a part of the information shown in FIG. The format of the print result list is arbitrary.

  FIG. 10 is a flowchart illustrating processing executed by the processor 212 according to the present embodiment. In the present embodiment, steps S203, S204, and S208 are different from the processing of the first embodiment.

  In step S201, the processor 212 acquires print image data. In step S202, the processor 212 acquires captured image data. The order of steps S201 and S202 may be reversed or may be simultaneous.

  In step S203, the processor 212 recognizes a page number from the print image data. In step S204, the processor 212 recognizes a page number from the captured image data. In step S205, the processor 212 performs a connected component labeling process on the print image data to generate first labeling data. In step S206, the processor 212 performs a connected component labeling process on the captured image data to generate second labeling data. The order of steps S203 to S206 is not limited to this order and may be interchanged.

  In step S207, the processor 212 performs an inspection by comparing the first labeling data with the second labeling data. The method of this comparative inspection is the same as the method of the first embodiment.

  In step S208, the processor 212 records the association between the page numbers of the print image data and the captured image data and the inspection results in the above-described print schedule list. The above processing is repeated until an instruction to end printing is received in step S209. The processor 212 may record the recorded print schedule list on the storage medium as the inspection result list.

  As described above, the processing device 210 according to the present embodiment recognizes the page information that specifies the page of the printed matter from the print image data, and generates an inspection result list in which the association between the page information and the inspection result is recorded. According to the present embodiment, even when the text data that is the basis of the print data cannot be obtained, the page information can be obtained by, for example, character recognition of the bitmap data (print image data) for printing. Generally, in character recognition from an image, it is difficult to obtain a recognition rate of 100% due to the effects of dirt or missing ink, dirt or expansion and contraction of paper, and the like. On the other hand, the print image data has less noise components such as dirt or missing ink, dirt or expansion and contraction of the paper, and a high recognition rate with little erroneous reading can be obtained as compared with the image data obtained by photographing the printed matter. For this reason, the print image data has high reliability as a master in creating inspection records and performing recovery production. Therefore, the print image data can be suitably used for collation with the inspection schedule number in the print schedule list and management of the character reading inspection of the printed matter.

  Since the print image data is simply image data, it is not very useful to record the image of the number as it is. However, if the page information is recognized from the print image data by a method such as character recognition, the utility value as the management number increases. The same effect can be obtained by recognizing not only characters but also two-dimensional codes such as bar codes and QR codes (registered trademark).

  In addition, a printing machine which is not assumed to be linked with the inspection apparatus usually has no mechanism for outputting a management number or the like. In order to perform number management on the inspection apparatus side, it is necessary to recognize characters in the read image. However, there is a risk of erroneous recognition due to problems such as dirt on ink, paper, and lenses. According to the method of the present embodiment, even in such a case, highly reliable number management can be performed.

  In a printing machine that is assumed to be linked with an inspection device, a number is often exchanged on a line different from a print image. However, there is a possibility that the timing of communication may be shifted due to the influence of the load on the communication line. In the method of the present embodiment, since raw image data is used, such a possibility is low, and the consistency between the printed matter and the data is not lost.

  A general printing machine or print controller converts text data such as a management number for specifying a page into image data and prints it. At this time, this conversion may not be performed normally for some reason. When this kind of malfunction occurs, there is a case where an illegal printing is performed not only on the management number but also on the entire page. Even in the above-described labeling inspection and other inspections, if the image data is incorrect, it is not possible to detect a defect in a printed matter printed as such.

  On the other hand, in the present embodiment, the image data of the management number is recognized from the print image data and collation with the scheduled number recorded in the list in advance can detect the improper image data. The inspection device outputs an error such as “the predicted number cannot be recognized” or “there is no number at the predicted position”, thereby preventing the outflow of defective products.

  Next, a modified example of the present embodiment will be described.

  The processing device according to the present embodiment performs the process of recognizing page information on both print image data and captured image data, but may omit the process of recognizing page information from captured image data. As described above, since the page information can be accurately recognized from the print image data, it is possible to appropriately manage the print inspection even if the recognition of the captured image data is omitted.

  In the present embodiment, similarly to the first embodiment, a process of performing labeling on each of the print image data and the captured image data and comparing the labeling data with each other is performed. The processing is not limited to such processing, and a processing for directly comparing two images as disclosed in Patent Document 1 may be applied. When such processing is adopted, the required amount of calculation increases, but the advantage of the inspection management according to the present embodiment can be obtained.

  FIG. 11 is a flowchart illustrating a process of the processor 212 according to a modification of the present embodiment. In this example, the processor 212 acquires print image data in step S301. In step S302, captured image data is obtained. In step S303, a page number is recognized from the print image data. In step S304, a page number is recognized from the captured image data. In step S305, an inspection is performed by comparing the print image data with the captured image data. The method of this inspection is not limited to the method of the first embodiment, and may be, for example, a method disclosed in Patent Document 1. In step S306, the relationship between each page number of the print data and the captured image data and the inspection result is recorded. Even when the processing shown in FIG. 11 is applied, management of the inspection result can be easily performed. In the processing shown in FIG. 11, step S304 may be omitted. In this case, the recording of the page number of the captured image data is omitted in step S306.

  The technology of the present disclosure can be used for checking whether or not a print result of a printed matter is appropriate. In particular, the present invention can be suitably used for the purpose of inspecting a result printed by a printing machine that performs digital variable printing.

DESCRIPTION OF SYMBOLS 10 Paper 100 Printing machine 110 Variable print controller 120 Print head 130 Conveyor 200 Inspection device 210 Processing device 212 Processor 214 RAM
216 ROM
220 imaging device 300 computer

Claims (8)

An inspection device that inspects printed matter printed by a printing machine that performs digital printing,
An imaging device for imaging the printed matter and outputting captured image data,
A processing device that performs inspection processing of the printed matter based on the print image data generated based on a print instruction input to the printing press and the captured image data,
With
The processing device includes:
Generating first labeling data by performing a connected component labeling process on the print image data;
Generating second labeling data by performing a connected component labeling process on the captured image data;
Inspecting the printed matter by comparing the first labeling data with the second labeling data, and outputting an inspection result;
Inspection equipment. The first labeling data includes at least one information of the number of connected components included in the print image data, the size of each connected component, and the position of each connected component,
The second labeling data includes at least one information of the number of connected components included in the captured image data, the size of each connected component, and the position of each connected component,
The processing device, between the print image data and the captured image data, by comparing at least one of the number of connected components, the size of each connected component, and the position of each connected component, in the printed matter Detect defects,
The inspection device according to claim 1. A data size of the first labeling data is smaller than 1/10 of a data size of the print image data;
A data size of the second labeling data is smaller than 1/10 of a data size of the captured image data;
The inspection device according to claim 1. The printing machine is a printing machine that performs variable printing on the conveyed paper,
The imaging device outputs the captured image data for each page,
The processing device performs an inspection based on a comparison between the first labeling data and the second labeling data for each page,
The inspection device according to claim 1.   A processing device used in the inspection device according to claim 1. An inspection device according to any one of claims 1 to 4,
The printing device;
A print inspection system comprising: An inspection method performed by an inspection device that inspects printed matter printed by a printing machine that performs digital printing,
Imaging the printed matter and outputting captured image data;
Print image data generated based on a print instruction input to the printing press, and performing an inspection process on the printed matter based on the captured image data;
Including
The step of performing the inspection processing includes:
Generating first labeling data by performing a connected component labeling process on the print image data;
Generating second labeling data by performing a connected component labeling process on the captured image data;
Inspecting the printed matter by comparing the first labeling data with the second labeling data, and outputting an inspection result;
Inspection methods, including: A program that defines processing performed by an inspection device that inspects printed matter printed by a printing machine that performs digital printing,
In the processor of the inspection device,
Obtaining print image data generated based on a print instruction input to the printing press;
An image capturing device acquiring captured image data generated by capturing the printed matter;
Generating first labeling data by performing a connected component labeling process on the print image data;
Generating second labeling data by performing a connected component labeling process on the captured image data;
Inspecting the printed matter by comparing the first labeling data with the second labeling data, and outputting an inspection result;
To run the program.

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