Inspection system, inspection apparatus and control method thereof, and program

Abstract

To prevent a waste rate from increasing due to a false determination in a label inspection caused in such a case that even an inspection target object in which dirt adheres to an area to be removed through the unnecessary part removal process is determined to be failed in the inspection.SOLUTION: An inspection apparatus reads a print product formed by an image forming device to obtain an inspection target image, obtains a reference image to be used in an inspection of the inspection target image, determines an inspection area to be targeted in an inspection in the reference image in accordance with whether or not an unnecessary part removal process for removing an unnecessary part of the print product is executed, and, based on the determined inspection area, performs the inspection by comparing the reference image and the inspection target image. When determining the inspection area, the inspection apparatus determines an area remaining after removing a part corresponding to the unnecessary part from the reference image to be the inspection area in a case of that the unnecessary part removal process is included.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to an inspection system, an inspection device, a control method thereof, and a program.

Background Art

[0002] In digital printing machines, it is required to inherit the high quality of offset printing machines and efficiently produce printed materials. In recent years, in order to balance the guarantee of the print quality of printed materials and productivity, an inspection device that performs quality inspection of printed materials on the conveyance path after printing has been proposed.

[0003] In printing such as book-shaped printing, when printing on large-sized recording paper, a trim mark indicating the cutting position is printed on the printed image. Then, in the post-process of the printing device, the cutting device performs cutting based on the cutting position specified by the trim mark. That is, the area inside the trim mark in the printed material is the area of the product to be delivered, and the area outside the trim mark is the area to be cut and discarded.

[0004] On the other hand, in seal label printing in which printing is performed on a sheet where a base paper and an adhesive paper overlap, cutting using a trim mark is not performed. The automatic cutting device uses CAD (Computer Aided Design) data to leave only the seal part used as a product on the base paper and remove only the adhesive paper other than the seal part. The process of removing the adhesive paper other than the seal part and leaving only the seal part on the base paper is called a scraping-up process. Whether to perform the scraping-up process is optional, and there are cases where the product is delivered with the adhesive paper other than the seal part attached to the base paper without performing the scraping-up process.

[0005] Patent Document 1 describes a printing device that, as a method of not performing unnecessary inspection on the medium part to be discarded in the cutting process, determines the outside of the trim mark as a cutting area and inspects only the inside of the trim mark when the cutting process is performed in the post-process.

Prior Art Documents

Patent Documents

[0006] Japanese Patent Document 1 Japanese Unexamined Patent Application Publication No. 2007-50546 Summary of the Invention Problems to be Solved by the Invention

[0007] However, in the technology of Patent Document 1, in the case of seal - label printing without printing trim marks, the cutting position cannot be specified, so the discarded part to be discarded also needs to be inspected. For this reason, even if the non - discarded image part of the printed matter is normal, if there is dirt or stain adhesion on the discarded part, the inspection will be NG. Therefore, a printed matter that should pass the inspection after the discarded part is removed may be judged as NG in the inspection. Therefore, in seal - label printing, it is required to exclude the discarded part to be discarded by the waste - raising process from the inspection target so as not to perform unnecessary inspections.

[0008] An object of the present invention is to solve at least one of the above - mentioned problems of the prior art.

[0009] Another object of the present invention is to provide a technique that eliminates unnecessary inspection processes by excluding unnecessary parts from the inspection target when a process of removing unnecessary parts of a printed matter is included, and reduces the possibility that a printed matter that should pass the inspection will be judged as NG. Means for Solving the Problems

[0010] In order to achieve the above object, an inspection apparatus according to an aspect of the present invention has the following configuration. That is, An inspection apparatus, a first acquisition means for reading a printed matter formed by an image forming apparatus and acquiring an inspection image; a second acquisition means for acquiring a reference image used for inspecting the inspection image; a determination means for determining an inspection area to be inspected in the reference image according to the presence or absence of a process of removing unnecessary parts of the printed matter; An inspection means for inspecting by comparing the reference image and the inspection image based on the inspection area determined by the determination means; When the determination means includes a process of removing an unnecessary part of the printed matter, the determination means is characterized in that a region obtained by removing the unnecessary part from the reference image is determined as the inspection region.

Advantages of the Invention

[0011] According to the present invention, when a process of removing an unnecessary part of a printed matter is included, it is possible to prevent an unnecessary inspection process from being performed on the removed region, so that a wasteful inspection process for the removed region is not performed.

[0012] Other features and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings. In the accompanying drawings, the same or similar components are denoted by the same reference numerals.

Brief Description of the Drawings

[0013] The accompanying drawings are included in the specification, form a part thereof, show embodiments of the present invention, and are used to explain the principle of the present invention together with the description.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Mode for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential to the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and duplicate explanations are omitted.

[0015] FIG. 1 is an overall configuration diagram of an image inspection system (print inspection system) according to an embodiment of the present invention. In the following description, the printing apparatus 100 may also be referred to as an image forming apparatus, a printer, a multifunction machine, a multifunction peripheral, or an MFP (Multi Function Peripheral).

[0016] A PC (Personal Computer) 300 is connected to the printing apparatus 100 via a LAN 400. Further, an inspection apparatus 200 is connected to the LAN 400. Note that the printing apparatus 100 and the inspection apparatus 200 are connected such that a print (media) printed by the printing apparatus 100 can be directly conveyed. The printing apparatus 100 and the inspection apparatus 200 may be collectively referred to as a print inspection apparatus.

[0017] The printing apparatus 100 is connected to a paper feeding unit 101. A control unit 104 controls the printing apparatus 100. The control unit 104 can control the printing apparatus 100 to be connected to the LAN 400. The paper feeding unit 101 can mount a roll paper used for seal / label printing, and a roll paper is installed in a roll paper winding unit 112. Note that the roll paper is one of the recording media in the present invention and can be applied to media of various shapes such as continuous form paper and cut paper. Further, it can also be applied to various printable materials such as cloth, plastic materials, and metal materials.

[0018] The recording medium fed from the paper feeding unit 101 is conveyed in the direction of arrow A. In this conveyance path, the recording medium passes through the cyan station 105, magenta station 106, yellow station 107, and black station 108, which are image forming units, and inks or toners of colors corresponding to each unit are transferred to form an image. Note that the method of forming an image on the recording medium is not particularly limited in the embodiment, and an electrophotographic method, an offset method, an inkjet method, etc. are conceivable. The fixing device 109 is a device that fixes color materials such as toner and ink to the recording medium. This also varies depending on the image forming method. For example, in the electrophotographic method, a thermocompression bonding method, and in the inkjet method, a drying method, etc. are conceivable.

[0019] After the fixing device 109, the reading sensor 201 of the inspection device 200 is arranged. The reading sensor 201 reads the image formed on the recording medium to acquire scanned image data. The reading sensor 201 is an image reading sensor using an element such as a CMOS (Complementary Metal Oxide Semicondacutor) sensor or a CCD (Carge Coupled Device), for example. Note that the reading sensor 201 may be a line sensor having the length in the main scanning direction of the recording medium or an area sensor. The reading sensor 201 converts the entire conveyed recording medium into high-resolution image data, for example, 300 dpi (dots per inch).

[0020] The inspection device 200 also includes a marking device 202, a recording paper winding device 203, and a control unit 204. The marking device 202 can attach a mark to an arbitrary location on the recording medium. This is used to attach a mark to a predetermined position of the recording medium determined to be NG by the inspection device.

[0021] As described above, a PC (Personal Computer) 300 is connected to the printing apparatus 100 via a LAN 400. The PC 300 is used to perform printing on the printing apparatus 100. In the embodiment, the PC 300 is described, but it is not necessary to be a PC, and any device that realizes processing for performing printing or a device that executes a program having such a function can be implemented.

[0022] The cutting apparatus 1000 is an apparatus that performs a half cut on a recording medium such as a seal label printed by the printing apparatus 100 in accordance with shape data (cut data) recorded by an electronic method such as CAD data. This cutting apparatus 1000 makes incisions only in the seal and label portions in the shape of the seal label, leaving the backing paper of the seal label. Inside the cutting apparatus 1000, roll paper winding units 1001 and 1002 are mounted, and the recording medium is conveyed in the direction of arrow B. During the conveyance, the recording medium is half cut directly below the cutter 1003 in accordance with the shape of the CAD data. As described above, since the cutting apparatus 1000 and a PC (Personal Computer) 300 are connected via the LAN 400, the PC 300 can transfer CAD data to the cutting apparatus 1000.

[0023] The peeling apparatus 1100 performs a so-called culling process of winding up and removing unnecessary adhesive paper other than the label of a recording medium such as a seal label that has been half cut by the cutting apparatus 1000. Inside the peeling apparatus 1100, roll paper winding units 1101, 1102, and 1103 are mounted, and the recording medium subjected to the culling process is conveyed in the direction of arrow C. The roll paper winding unit 1103 is a winding unit that winds up unnecessary adhesive paper separated by the separating apparatus 1104 by the culling process. The roll paper winding unit 1102 is a unit that winds up a recording medium including seals and labels from which unnecessary adhesive paper has been removed. In the embodiment, the peeling apparatus 1100 is not connected to the network 400, but the present invention is not limited to this. For example, by connecting to the network 400, it is also possible to perform control and data sharing with the PC 300.

[0024] FIG. 2 is a block diagram for explaining the hardware configuration of each device included in the image inspection system according to the embodiment.

[0025] The printing device 100 is connected to the LAN 400 via the network controller 120. The processes executed by the printing device 100 are realized by expanding the program stored in the storage device 121 into the memory 123 and then having the CPU 122 execute the expanded program. These storage device 121, CPU 122, and memory 123 correspond to the control unit 104 in FIG. 1. The printing device 100 also has an operation unit 124 and can display on the screen of the operation unit 124 to receive input operations from the outside. The image processing unit 125 converts electronic image data (for example, multi-value image data of CIE-sRGB) into electronic image data for printing (for example, halftone image of CMYK). Further, the electronic image data for printing is transferred to the printing processing unit 126, and an image is printed on the recording paper fed from the paper feeding unit 101 using the image forming stations 105 to 108 in FIG. 1. The GPU 127 controls the operation of the printing device 100 in cooperation with the CPU 122.

[0026] The inspection device 200 is connected to the LAN 400 via the network controller 221. The processing executed by the inspection device 200 is realized by expanding the program stored in the storage device 222 into the memory 224 and then executing the expanded program by the CPU 223. Further, the CPU 223 uses the reading unit 225 connected to the reading sensor 201 to convert the image of the recording medium into electronic image data (for example, RGB multi-value image data). These storage device 222, CPU 223, and memory 224 correspond to the control unit 204 in FIG. 1. The operation unit 226 also functions as a display unit that displays an inspection setting screen described later and accepts input from the user. Note that the display unit may have a touch panel function. Further, the screen displayed on the display unit is controlled by the CPU 223, and in the embodiment, the CPU 223 may also be referred to as a display control unit. Further, the GPU 227 is mounted, and by speeding up the inspection process, the inspection time per page can be made shorter than the printing time. In the embodiment, it is described that the inspection device 200 connected to the subsequent stage of the printing device 100 performs the inspection process, but the present invention is not limited thereto. For example, an inspection PC that specializes in inspection processing may be connected to an inspection device that mainly performs imaging via a communication unit, and the inspection PC that receives the image captured by the inspection device may execute the inspection process based on the inspection settings received by the inspection PC.

[0027] The PC 300 is connected to the LAN 400 via the network controller 301 that gives a printing instruction to the printing device 100. The processing executed by the PC 300 is realized by the CPU 303 expanding the program stored in the storage device 302 into the memory 304 and then executing the expanded program by the CPU 303. Further, the operation unit 305 has a display (not shown) and can display a screen. Further, a pointing device or a keyboard (not shown) can be connected to accept the operation of the user.

[0028] FIG. 3 is a functional block diagram for explaining the processing by the programs stored in the storage device 222 of the inspection device 200, the storage device 121 of the printing device 100, and the storage device 302 of the PC 300 according to the embodiment.

[0029] FIG. 3(a) is a functional block diagram for explaining the processing executed by the program stored in the storage device 121 of the printing apparatus 100. FIG. 3(b) is a functional block diagram for explaining the processing executed by the program stored in the storage device 222 of the inspection apparatus 200. FIG. 3(c) is a functional block diagram for explaining the processing executed by the program stored in the storage device 302 of the PC 300. The explanations of the processing of each program shown in FIG. 3 will be described in detail hereinafter.

[0030] As described above, the printing apparatus 100, the inspection apparatus 200, and the PC 300 each include an operation unit 124, an operation unit 226, and an operation unit 305. Further, the CPU 122 of the printing apparatus 100, the CPU 223 of the inspection apparatus 200, and the CPU 303 of the PC 300 are assumed to have a function of generating HTML (HyperTerminal Markup Language) for display on each screen using a program. Therefore, display and operation on each operation unit are possible using HTTP (HyperText Transfer Protocol). Thus, in the present embodiment, the apparatus for receiving display and operation and the display are not limited.

[0031] [Embodiment 1] FIG. 4 is a sequence diagram for explaining the flow of processing in the image inspection system according to Embodiment 1. Hereinafter, printing and inspection processing will be described with reference to this sequence diagram.

[0032] In S401, when the CPU 303 of the PC 300 receives a printing command from the operation unit 305, it executes the print data creation process 310 in FIG. 3(c) to create print data. At this time, the print data creation process 310 displays the print setting screen shown in FIG. 5(a) on the operation unit 305 of the PC 300.

[0033] FIG. 5(a) is a diagram showing an example of a print setting screen displayed on the operation unit 305 of the PC 300, and FIGS. 5(b) to 5(d) are diagrams showing example screens when registering a print sample image displayed on the operation unit 226 of the inspection apparatus 200. FIGS. 5(e) and 5(f) are diagrams showing an example screen for displaying the inspection result and an example screen showing the inspection result, which are displayed on the operation unit 226 of the inspection apparatus 200.

[0034] In the example screen of FIG. 5(a), it is possible to set the width 505 of the image to be printed, the size 504 in the feed direction, the number of printed copies 508, the page interval 507, and the ON / OFF 506 of automatic inspection. The print command includes the information input from the screen of FIG. 5(a). In the first embodiment, it is described that the ON / OFF 506 of automatic inspection is always set to ON. The print data created here is composed of images such as JPEG and TIFF, text data, font information used for text data, and graphics drawing data. Further, cutting data (cutting information) for performing a half cut by the cutting device 1000 may be included. Although the print data is often created in the PDF (Portable Document Format) format, the present invention is not limited to this, and print data using an original format may be adopted. The cancel button 502 is a button for canceling all the settings on this screen and returning to the original screen. The print button 501 is a button for instructing to perform printing according to the contents set on this setting screen.

[0035] Next, in S402, the CPU 303 of the PC 300 transmits the print data created in S401 to the printing device 100 via the LAN 400 based on the instruction of the print button 501.

[0036] In S403, the CPU 122 of the printing apparatus 100 executes the RIP process 130 in FIG. 3(a) to perform a RIP process of expanding the received print data into raster image data and create image data. Here, the RIP process refers to the (Raster Image Processor) process, which means a process of generating image data from the received print data. Specifically, it is to interpret the PDL language including character and image data and convert it into raster image data. The image data created here is image data composed of color information such as CMYK. Incidentally, at this time, if the print data includes cutting data, the RIP process 130 creates a raster image specifying the cutting area with a line. Then in S404, the CPU 122 of the printing apparatus 100 transmits the image data (raster image data) created in S403 to the inspection apparatus 200 via the LAN 400.

[0037] In S405, the CPU 223 of the inspection apparatus 200 executes the sample image creation process 236 in FIG. 3(b). Specifically, based on the image data received in S404, a print sample image (reference image) for image inspection is created and displayed on the operation unit 226. For example, if the image data is a CMYK image, the print sample image is created by converting it into RGB image data through a color conversion process using the ICC profile stored in the storage device 222 in advance.

[0038] FIG. 5(b) is a diagram showing an example of an approval screen of the print sample image (reference image) displayed on the operation unit 226 of the inspection apparatus 200.

[0039] The image display area 511 is a display area for the operator to visually check the printed sample image. Thus, the operator can visually check the printed sample image displayed in this image display area 511. When the operator indicates the OK button 509 via the operation unit 226 if the displayed printed sample image is satisfactory, the CPU 223 proceeds to the process in S406. On the other hand, when the operator is not satisfied with the displayed printed sample image, the operator indicates the cancel button 510 from the operation unit 226. In this case, all processes are stopped and the creation process of the printed sample image is terminated.

[0040] In S406, the CPU 223 of the inspection apparatus 200 executes the inspection area registration process 237 in FIG. 3(b). FIGS. 5(c) to (d) illustrate the screens of the inspection area registration process.

[0041] FIG. 5(c) is an example of a screen when no culling is performed in the subsequent process, and the entire page is inspected. On the other hand, FIG. 5(d) is an example of a screen when culling is performed in the subsequent process, and only the design part on the recording medium is inspected.

[0042] In FIG. 5(c), since no culling is performed, the check box 517 for "excluding unnecessary parts" is not checked, and the reference button 514 for cutting data is not used either. The display area 518 is an area for displaying the entire printed sample image. On the other hand, in FIG. 5(d), since culling is performed, the check box 517 for "excluding unnecessary parts" is checked. Also, the file (File: / / xxx) of the cutting data is selected and displayed by the reference button 514 for cutting data. Note that the details of this process and the illustrated screen will be described later.

[0043] Next, in S407, the CPU 223 of the inspection apparatus 200 saves the sample image and the inspection area settings created in S405 and S406 in the storage device 222. By the processes of S401 to S407 described above, the sample image and the inspection area are saved in the inspection apparatus 200 of the first embodiment.

[0044] Next, the inspection process according to Embodiment 1 will be described.

[0045] In S408, the CPU 122 of the printing apparatus 100 executes the printing process 131 in FIG. 3(a). In this printing process 131, the RIP image generated in the storage area in S403 is read out, and the printing process 131 is executed. In the printing process 131, after performing halftone processing on the four-color RIP image (CMYK) using the image processing unit 125, an image is transferred to the recording medium by each of the stations 105 to 108 according to the signal value. The image thus transferred is fixed to the recording medium by the fixing device 109 and then conveyed directly below the reading sensor 201 of the inspection apparatus 200.

[0046] Then, in S409, the CPU 223 of the inspection apparatus 200 executes the reading process 232 in FIG. 3(b), and reads and acquires the size of one page in the feeding direction of the recording medium printed in S408 by the reading sensor 201. Then, the acquired image is stored in the memory 224 as an inspection image.

[0047] Next, in S410, the CPU 223 of the inspection apparatus 200 executes the defect inspection process 233 in FIG. 3(b). In this defect inspection process 233, the sample image 511 in FIG. 5(b) acquired in S407 and the inspection image acquired in S409 are compared within the inspection area determined in S406, and if there is a difference, it is determined as a defect. Specifically, feature points are extracted from each of the sample image (reference image) and the inspection image, and the sample image and the inspection image are aligned based on the extracted feature points. If the difference between the pixel value (luminance value) of the pixel to be inspected in the aligned inspection image and the pixel value (luminance value) of the comparison target pixel in the sample image is equal to or less than the threshold value, the defect inspection process 233 determines that the pixel to be inspected is qualified. Note that this threshold value is different for each inspection level that determines the strictness of the inspection.

[0048] When the inspection of all pixels is thus completed, it is determined whether the inspection image is normal based on whether the total number of pixels determined to be non-conforming is less than or equal to the pass threshold. If the total value of the pixels determined to be non-conforming is less than or equal to the pass threshold, the defect inspection process 233 determines that the inspection image is normal. On the other hand, if the total value of the pixels determined to be non-conforming exceeds the pass threshold, the defect inspection process 233 determines that the inspection image is not normal (NG). Then, in S411, the CPU 223 of the inspection device 200 displays the inspection result of the inspection image being inspected on the operation unit 226.

[0049] FIG. 5(e) is a diagram showing an example of a screen for displaying an inspection result.

[0050] In the display area 522, the inspection image being inspected is displayed, and the defect 520 found in the inspection of S410 is synthetically displayed so as to be prominent. This screen also has a stop button 525. When the pressing of the stop button 525 is received, the CPU 223 of the inspection device 200 sends an emergency stop command to the CPU 122 of the printing device 100. When the CPU 122 of the printing device 100 receives this emergency stop command, it can issue a command to the printing processing unit 126 to stop printing.

[0051] Then, in S412, the CPU 223 of the inspection device 200 notifies the printing device 100 of the inspection result for one page in the feed direction. For example, when a prescribed number or more of defective locations are found, there is a high possibility that a malfunction has occurred in the image forming stations 105 to 108. In order to make such a determination, it is necessary to always transmit the inspection result from the inspection device 200 to the printing device 100 to share the inspection result.

[0052] In S413, the CPU 223 of the inspection device 200 performs a paper discharge process. At this time, a mark may be attached by the mark attaching device 202 at the location determined to be defective in the inspection of S410, for example, at the position of the defect 520 in FIG. 5(e). In this way, the CPU 223 of the inspection device 200 executes the processes of S409 to S413 for the number of printed sheets. Finally, in S414, the CPU 223 of the inspection device 200 displays the final inspection result on the operation unit 226.

[0053] FIG. 5(f) is a diagram showing an example of a screen of the final inspection result. The number of defects 521 in all printed pages, the list 519 of defect locations, and the image 523 of the inspection image where the defect was found are arranged. When the operator finishes checking this screen, the operator presses the OK button 524. In the example of FIG. 5(f), it is displayed that defects were detected in 5 out of 10,000 printed materials with the number of defects 521. And an example of "defect 1" selected in the list 519 of defect locations is displayed in the image 523 of the inspection image.

[0054] Next, the inspection area registration process 237 executed by the CPU 223 of the inspection device 200 in S406 will be described with reference to the screen examples of FIGS. 5(c) and 5(d) and the flowchart of FIG. 6.

[0055] FIG. 6 is a flowchart for explaining the registration process of the inspection area executed by the inspection device 200 according to Embodiment 1. The process shown in this flowchart is achieved by the CPU 223 of the inspection device 200 executing a program developed in the memory 224.

[0056] In S601, the CPU 223 determines whether to perform the exclusion (cusp raising) of unnecessary parts. For example, when the CPU 223 receives that the checkbox 517 in FIG. 5(c) is checked, it is determined that cusp raising for excluding unnecessary parts is performed and the process proceeds to S602. If the checkbox 517 is not checked, the process proceeds to S605. In addition, when the print data created in S401 includes the presence / absence information of the peeling device 1100 and the presence / absence information indicates that the peeling device 1100 is connected (presence of the peeling device 1100), the checkbox 517 may be checked as an initial value.

[0057] In S602, the CPU 223 determines whether the cutting data exists in the storage device 222 or the memory 224. The cutting data may be transferred simultaneously as meta-information of the image data received in S404. If there is no cutting data in the meta-information, the pressing of the reference button 514 may be accepted, and the CAD data stored in the storage device 302 of the PC 300 or data obtained from an external storage device (not shown) may be used. Thus, in S602, when the cutting data can be obtained by some method, the CPU 223 proceeds with the process to S603. If the cutting data cannot be obtained, the process proceeds to S604. In S604, the CPU 223 determines the inspection area based on the image data. This process will be described in detail later. In S603, the CPU 223 determines the inspection area using the cutting data.

[0058] Figs. 7(a) to (c) are diagrams for explaining the determination process of the inspection area based on the cutting data, and Figs. 7(d) to (f) are diagrams for explaining the determination process of the inspection area based on the image data.

[0059] Fig. 7(a) is a diagram showing an example of the cutting data.

[0060] Along the cutting line 701, the cutting device 1000 performs a half cut. However, considering the registration accuracy of the cutting device 1000 and the registration accuracy of the printing device 100, it is necessary to inspect the inspected product up to the outside of the actual cutting line. Therefore, as shown in Fig. 7(b), it is necessary to expand the area outward (in the arrow direction) from the cutting line 701, and based on the center of the area surrounded by the cutting line 701, for example, a 10% enlargement process is performed to set an inspection boundary line 702 showing the enlarged area. Note that for the 10% of the predetermined amount of enlargement, a value based on factors such as registration accuracy may be set, and the present invention is not particularly limited thereto. The outside of the inspection boundary line 702 is a non-inspection area 704 that is not the object of inspection, and the inside is the inspection area 705. Finally, the image of Fig. 7(c) obtained by synthesizing the image data 703 and the inspection boundary line 702 is displayed in the display area 518 of Fig. 5(d). The boundary line 527 in Fig. 5(d) corresponds to the inspection boundary line 702 in Fig. 7(c).

[0061] Also in S605, the CPU 223 determines that no escalation is to be performed and will inspect the entire page. In this case, the inspection is carried out within the inspection range 526 displayed in the display area 518 of Fig. 5(c), and the setting is to inspect all of the printed surface.

[0062] Next, in S604 of Fig. 6, a method of creating an inspection boundary line from the values of each pixel of the image data will be described using the flowchart of Fig. 8.

[0063] Fig. 8 is a flowchart for explaining the registration process of the inspection area based on the image data of S604 in Fig. 6.

[0064] First, in S801, the CPU 223 of the inspection device 200 reads the image data transferred in S404 from the storage device 222. Next, proceeding to S802, the CPU 223 specifies the foreground portion in the image data and performs edge extraction. As a method for specifying this foreground portion, there is a method of determining the non-white area of the image data as the foreground layer. The foreground layer is the image data before being synthesized with the background layer when the RIP process 130 creates the image data, and is represented by, for example, (C, M, Y, K) ≠ (0, 0, 0, 0). In contrast, the background layer is set to the original color of the printed matter, for example, (C, M, Y, K) = (0, 0, 0, 0).

[0065] The designed image data is drawn on the foreground layer, and since nothing is drawn on the background layer, it is composed of white pixels. If the design of the foreground layer also has the same white pixels as the background layer, in the RIP process 130, data such as (C, M, Y, K) = (0, 0, 1, 0) is added to the foreground layer. As a result, although no difference can be visually confirmed, the foreground layer and the background layer can be distinguished by rewriting to non-white pixels for distinguishing from the background layer. However, this is not the case when the background layer is not white and a color is used.

[0066] FIG. 7(d) is a diagram illustrating the outline line 706 of an object which is a foreground layer included in the image data. In FIG. 7(d), the portion illustrated as a non-white area with cross-hatching is the foreground layer, and the foreground layer is specified by the line of the outline 706.

[0067] Next, proceeding to S803, the CPU 223 corrects the outline 706 created in S802 to create an inspection boundary line. The process of S803 will be described with reference to FIG. 7(e).

[0068] Similar to FIG. 7(b), the inspection boundary line corresponding to the outline 706 is enlarged to set the inspection boundary line 702. The outside of this inspection boundary line 702 is the non-inspection area 707, and the inside thereof is the inspection area 708. Finally, the image data 703 corresponding to the foreground layer and the inspection boundary line 702 are combined to obtain the image of FIG. 7(f), and the image is displayed in the display area 518 of FIG. 5(d). Thus, the detailed description of S604 ends here.

[0069] As described above, according to the first embodiment, when cusp raising is performed in the subsequent stage, regardless of the presence or absence of trim marks and cutting data, only the area that is not discarded in the subsequent process can be set as the inspection target area. Thereby, it is possible to eliminate the wasteful inspection process including the discarded portion, and it is also possible to prevent the notification of result NG due to the defect of the image of the discarded portion and the discard of the printed matter.

[0070] [Second Embodiment] In the second embodiment, an embodiment in the case of applying the inspection using the RIP image described in the first embodiment as a sample image to a scan inspection using the read image of the sample print as the sample image will be described. The second embodiment enables inspection even in an environment where image data transfer between, for example, a printing device and an inspection device is not possible. Note that the description of the same configuration and the same process as those in the first embodiment will be omitted as appropriate.

[0071] FIG. 9 is a sequence diagram for explaining the processing flow in the image inspection system according to Embodiment 2. Hereinafter, printing and inspection processing will be described with reference to this sequence diagram. In FIG. 9, the same reference numerals are assigned to the processes common to the aforementioned FIG. 4, and their descriptions are omitted.

[0072] The printing process of S901 is basically the same as S408 in FIG. 4. However, since S901 is printing for creating a sample image, assuming that it is printed correctly, printing for one page in the feed direction is performed. The registration process of the inspection area in S902 is different from S604 which is the internal process of S406 in FIG. 4, and its description will be given later.

[0073] FIG. 10 is a flowchart for explaining the registration process of the inspection area in S902 of FIG. 9. In FIG. 10, since the processes of S1001 to S1003 and S1005 are the same as S601 to S603, S605 in FIG. 6, their descriptions are omitted.

[0074] FIG. 11 is a flowchart for explaining the process of determining the inspection area based on the image data of S1004 in FIG. 10.

[0075] In S1101, the CPU 223 of the inspection device 200 reads the image data for determining the inspection area. As a method for reading the image data, a method using the sample image created in S405 can be considered. In addition, a method of acquiring the image data created by the printing device 100 in S403 and a method of acquiring the image data from the PDF file used in S401 can also be considered. The image data in this case does not need to be limited to the printing image and is not limited in this embodiment.

[0076] Next, proceeding to S1102, the CPU 223 performs region division processing on the image data read in S1101. As this region division method, for example, there is a division method using clustering processing such as the K-means method. In this process, classes are integrated based on the distance and similarity between pixels constituting the image data, and finally, it becomes a large group called a superpixel as shown in FIG. 7(g).

[0077] In FIG. 7(g), the sample image is divided into seven groups, and only group 709 among them constitutes the foreground of the sample image. The other groups constitute the background and have the same RGB values as the recording medium. In this region division process, since only the foreground needs to be extracted, it is sufficient to identify only the pixel coordinates that make up group 709.

[0078] Next, proceeding to S1103, the CPU 223 performs edge extraction of group 709 identified in S1102. In this process, the outermost pixels of group 709 are connected to generate an edge extraction line. Since the edge extraction line correction process in S1104 is the same as the process in S803 described above, the description thereof is omitted.

[0079] Note that the method for determining the inspection area in S1004 of the second embodiment can be implemented as an alternative means for S604 of the first embodiment. Also, as an alternative means for S604 of the first embodiment, S1004 may be implemented.

[0080] As described above, according to the second embodiment, in an inspection apparatus that reads a printed matter to obtain a sample image, when cusp raising is performed in a subsequent stage, regardless of the presence or absence of trim marks and cutting data, an area that is not discarded in a subsequent process can be set as the inspection area. As a result, unnecessary inspection processing including the discarded portion can be eliminated, and it is possible to prevent a result NG notification or the discarding of the printed matter due to a defect in the image of the discarded portion.

[0081] (Other Embodiments) The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and having one or more processors in a computer of the system or apparatus read and execute the program. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

[0082] This specification and the drawings disclose the following inspection system, inspection device, its control method, and program.

[0083] [Item 1] An inspection device, comprising: a first acquisition means for reading a printed matter formed by an image forming device to acquire an inspection image; a second acquisition means for acquiring a reference image used for inspecting the inspection image; a determination means for determining an inspection area to be inspected in the reference image according to the presence or absence of a process for removing unnecessary portions of the printed matter; an inspection means for comparing and inspecting the reference image and the inspection image based on the inspection area determined by the determination means. The determination means determines, when the process for removing unnecessary portions of the printed matter is included, an area obtained by removing the unnecessary portions from the reference image as the inspection area. The inspection device is characterized by this.

[0084] [Item 2] The second acquisition means acquires the reference image based on image data used for forming the printed matter. The inspection device according to Item 1 is characterized by this.

[0085] [Item 3] The determination means determines the inspection area based on cutting information referred to in the process for removing unnecessary portions of the printed matter. The inspection device according to Item 2 is characterized by this.

[0086] [Item 4] The determination means determines the inspection area based on an enlarged area obtained by enlarging the area indicated by the cutting information by a predetermined amount with the approximate center of the area as a reference. The inspection device according to Item 3 is characterized by this.

[0087] [Item 5] The cutting information is included in the image data used for forming the printed matter. The inspection device according to Item 3 is characterized by this.

[0088] [Item 6] The inspection apparatus according to item 1, wherein the second acquisition means acquires, as the reference image, the image data obtained by reading the printed matter.

[0089] [Item 7] The inspection apparatus according to any one of items 1 to 6, wherein the presence or absence of the process of removing the unnecessary portion of the printed matter is determined according to whether or not a cutting device is connected to the inspection apparatus.

[0090] [Item 8] The inspection apparatus according to any one of items 2 to 6, wherein the determination means determines the inspection area based on the image data corresponding to the foreground layer in which the designed image data included in the reference image is drawn.

[0091] [Item 9] The inspection apparatus according to any one of items 2 to 6, wherein the determination means performs an area division process on the reference image, and determines the inspection area based on an area including the foreground layer in which the designed image data is drawn among the plurality of areas obtained by the area division process.

[0092] [Item 10] The inspection apparatus according to item 9, wherein the determination means determines the inspection area by performing the area division process when not receiving the cutting information referred to in the process of removing the unnecessary portion of the printed matter.

[0093] [Item 11] The inspection apparatus according to item 8 or 9, wherein the foreground layer is represented by (C, M, Y, K) ≠ (0, 0, 0, 0) when the printed matter is white.

[0094] [Item 12] The inspection apparatus according to any one of items 1 to 11, wherein the determination means determines the entire reference image as the inspection area when the process of removing the unnecessary portion of the printed matter is not included.

[0095] [Item 13] The inspection apparatus according to any one of Items 1 to 12, wherein the process of removing the unnecessary part of the printed matter is a cusp raising process.

[0096] [Item 14] An inspection system having the inspection apparatus according to any one of Items 1 to 13 and an image forming apparatus that generates a printed matter with an image printed on a recording medium, wherein the inspection apparatus inspects the printed matter generated by the image forming apparatus.

[0097] [Item 15] A control method for controlling an inspection apparatus, a first acquisition step in which first acquisition means reads a printed matter formed by an image forming apparatus to acquire an inspection image; a second acquisition step in which second acquisition means acquires a reference image used for inspecting the inspection image; a determination step in which determination means determines an inspection region to be inspected in the reference image according to the presence or absence of a process of removing an unnecessary part of the printed matter; an inspection step in which inspection means compares the reference image and the inspection image based on the inspection region determined in the determination step to perform an inspection, and in the determination step, when the process of removing the unnecessary part of the printed matter is included, the region obtained by removing the unnecessary part from the reference image is determined as the inspection region.

[0098] [Item 16] A program for causing a computer to function as each means of the inspection apparatus according to any one of Items 1 to 13.

[0099] The present invention is not limited to the above embodiments, and various changes and modifications can be made without departing from the spirit and scope of the present invention. Therefore, the following claims are appended to disclose the scope of the present invention.

Description of Signs

[0100] 100... Printing device, 200... Inspection device, 201... Reading sensor, 233... Defect inspection process, 237... Inspection area registration process, 702... Inspection boundary line, 705, 708... Inspection area, 706... Outlining, 1000... Cutting device, 1100... Peeling device

Claims

1. An inspection device, comprising: a first acquisition means for reading a printed matter formed by an image forming device and acquiring an inspection image; a second acquisition means for acquiring a reference image used for inspecting the inspection image; a determination means for determining an inspection area to be inspected in the reference image according to the presence or absence of a process for removing an unnecessary portion of the printed matter; an inspection means for comparing and inspecting the reference image and the inspection image based on the inspection area determined by the determination means; wherein, when the process for removing the unnecessary portion of the printed matter is included, the determination means determines, as the inspection area, an area obtained by removing the unnecessary portion from the reference image. The inspection device is characterized by this.

2. The inspection device according to claim 1, wherein the second acquisition means acquires the reference image based on image data used for forming the printed matter.

3. The inspection device according to claim 2, wherein the determination means determines the inspection area based on cutting information referred to in the process for removing the unnecessary portion of the printed matter.

4. The inspection device according to claim 3, wherein the determination means determines the inspection area based on an enlarged area obtained by enlarging the area indicated by the cutting information by a predetermined amount with the approximate center of the area as a reference.

5. The inspection device according to claim 3, wherein the cutting information is included in the image data used for forming the printed matter.

6. The inspection device according to claim 1, wherein the second acquisition means acquires, as the reference image, image data obtained by reading the printed matter.

7. The inspection device according to claim 1, wherein the presence or absence of the process for removing the unnecessary portion of the printed matter is determined according to whether a cutting device is connected to the inspection device.

8. The inspection device according to claim 2 or 6, wherein the determination means determines the inspection area based on image data corresponding to a foreground layer in which designed image data included in the reference image is drawn.

9. The inspection device according to claim 2 or 6, wherein the determination means performs an area division process on the reference image, and determines the inspection area based on an area including a foreground layer in which designed image data is drawn among a plurality of areas obtained by the area division process.

10. The inspection apparatus according to claim 9, wherein the determination means determines the inspection area by performing the area division process when not receiving cutting information referred to in a process of removing an unnecessary part of the printed matter.

11. The inspection apparatus according to claim 8, wherein the foreground layer is represented by (C, M, Y, K) ≠ (0, 0, 0, 0) when the printed matter is white.

12. The inspection apparatus according to claim 1, wherein the determination means determines the entire reference image as the inspection area when the process of removing an unnecessary part of the printed matter is not included.

13. The inspection apparatus according to claim 1, wherein the process of removing an unnecessary part of the printed matter is a cusp raising process.

14. An inspection system having the inspection apparatus according to claim 1 and an image forming apparatus that generates a printed matter with an image printed on a recording medium, wherein the inspection apparatus inspects the printed matter generated by the image forming apparatus.

15. A control method for controlling an inspection apparatus, a first acquisition step in which a first acquisition means reads a printed matter formed by an image forming apparatus to acquire an inspection image; a second acquisition step in which a second acquisition means acquires a reference image used for inspection of the inspection image; a determination step in which a determination means determines an inspection area to be inspected in the reference image according to the presence or absence of a process of removing an unnecessary part of the printed matter; an inspection step in which an inspection means compares and inspects the reference image and the inspection image based on the inspection area determined in the determination step, and the determination step determines, as the inspection area, an area obtained by removing the unnecessary part from the reference image when the process of removing the unnecessary part of the printed matter is included.

16. A program for causing a computer to execute each step of the control method according to claim 15.

Images