Inspection method and device

Abstract

To solve the problem that, when layout analysis or the like is performed in order to determine a technique of character recognition processing, a target inspection speed cannot be achieved in some cases because the analysis itself requires processing time.SOLUTION: Fonts and techniques of character recognition processing are preliminarily registered in association with each other. Further, an inspection area where a character string is to be inspected and a font to be used for the inspection area are preliminarily set. Then, a technique of character recognition processing to be applied to the inspection area is determined on the basis of the font to be used for the inspection area preliminarily set and the technique of character recognition processing registered in association with the font, and character recognition processing on an image corresponding to the inspection area is performed using the determined technique of character recognition processing.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a method and apparatus for inspecting the print quality of printed matter. [Background technology]

[0002] Recently, printing systems have become known in which an inspection device inspects printed sheets while the sheets are being transported by a printing device. In this inspection, the inspection device reads an image of the transported sheet and analyzes the image to determine whether printing on the sheet was performed properly. Such inspection devices can detect missing characters or barcodes printed on the printed material, missing images, printing defects, missing pages, color misalignment, and other issues. If a printed sheet is determined to be defective, the defective sheet is ejected to a different destination from normal sheets. This prevents defective sheets from being mixed in with normal sheets and allows the operator to discard the defective sheets.

[0003] In such systems, when inspecting whether a character string portion is printed correctly, an inspection device is known that performs character recognition processing on the area where the character string is printed and performs a comparison inspection in which the recognition result is compared with correct data. In the above-mentioned system, when switching the paper output destination, the character recognition processing and comparison processing must be completed during the sheet transport period from when the printed sheet is read to when the paper output destination is switched, and therefore, both speed and accuracy of the character recognition processing are required. Patent Document 1 describes a method in which a layout analysis is performed on a document, and character recognition processing is performed with priority given to recognition accuracy in areas where misrecognition is desired to be avoided, and character recognition processing with priority given to processing speed in areas where a certain degree of misrecognition is acceptable. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-43316 Summary of the Invention [Problem to be solved by the invention]

[0005] However, image analysis itself, such as layout analysis for determining the character recognition processing method, also incurs processing time overhead, and there are cases where the desired inspection speed cannot be achieved. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, an inspection device of the present invention is an inspection device having an inspection means for inspecting a read image obtained by reading the image on the recording material conveyed from a conveying means that receives the recording material on which an image has been printed from a printing device that has printed the image on the recording material, and conveys the recording material, and before the inspection is performed by the inspection means, a registration means for registering a font and a character recognition processing method in association with each other; and a setting means for setting an inspection area in which a character string is inspected and a font to be used in the inspection area. The inspection means comprises: determining a character recognition processing method to be applied to the inspection area based on the font used in the inspection area set by the setting means and the character recognition processing method associated with the font by the registration means, and using the determined character recognition processing method, The reading The method is characterized in that character recognition processing is performed on an image corresponding to the inspection area within the image. [Effects of the Invention]

[0007] By determining the character recognition processing method prior to inspection, the inspection speed can be improved. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of an information processing device, an inspection device, and a printing device. [Figure 2] FIG. 1 is a block diagram showing the configurations of an information processing device, an inspection device, and a printing device. [Figure 3]FIG. 2 is a diagram showing the internal configuration of an information processing device, an inspection unit, a printing device, and a large-capacity stacker. [Figure 4] Flowchart of the entire test. [Figure 5] FIG. 10 is a diagram showing a font registration screen. [Figure 6] FIG. 10 is a diagram showing a character segmentation screen. [Figure 7] 10 is a flowchart for font registration. [Figure 8] FIG. [Figure 9] FIG. [Figure 10] 1 is a flowchart of the test setup. [Figure 11] Inspection flowchart. [Figure 12] 10 is a flowchart of an inspection setting according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Below, we will explain the form for implementing the present invention using drawings, but the following form does not limit the invention related to the claims, and not all of the combinations of features described in the form are necessarily essential to the solution of the invention.

[0010] [First embodiment] 1 is a schematic diagram showing the configuration of an information processing device, an inspection device, and an image forming device in this embodiment. Note that, although the image forming device in this embodiment will be described using an electrophotographic image forming device, the image forming device in this embodiment may be an image forming device of a different image forming method, such as an inkjet method or an offset method.

[0011] The image forming apparatus 0101 is connected to an information processing apparatus 0109 via a communication cable 0112. The information processing apparatus 0109 is connected to a client computer 0110 and an inspection apparatus 0108 via a network 0113. The image forming apparatus 0101 includes a UI panel 0102, a paper feed deck 0103, and a paper feed deck 0104. An optional deck 0105 consisting of three paper feed decks is also connected. The image forming apparatus 0101 is, for example, an electrophotographic image forming apparatus. The UI panel 0102 is, for example, a user interface equipped with a capacitive touch panel.

[0012] The image forming apparatus 0101 further includes an inspection unit 0106 and a large-capacity stacker 0107. The inspection unit is connected to an inspection device 0108 via a communication cable 0114. The large-capacity stacker 0107 includes a main tray and a top tray, and the main tray can hold several thousand sheets of paper at a time.

[0013] A print job is generated by the client computer 0110, transmitted to the information processing device 0109 via the network 0113, and managed by the information processing device 0109. The print job is then transmitted from the information processing device 0109 to the image forming device 0101 via the communication cable 0112, and the image forming device 0101 performs processing to print on paper based on the received print job. Note that the print job may also be generated and managed by the information processing device 0109, transmitted to the image forming device 0101 via the network 0112, and managed by the image forming device 0101.

[0014] The client computer 0110, the information processing device 0109, and the inspection device 0108 may be connected to a cable 0112 to communicate with the image forming device 0101. That is, the connection configuration of the image forming device 0101, the information processing device 0109, and the client computer 0110 shown in this embodiment is just an example, and it goes without saying that there are various other connection configurations besides that shown in this embodiment.

[0015] FIG. 2 is a block diagram showing the control configuration of the image forming apparatus 0101, the inspection apparatus 0108, the large-capacity stacker 0107, the information processing apparatus 0109, and the client computer 0110 in this embodiment.

[0016] The CPU (Central Processing Unit) 0201 controls and performs calculations for each component within the image forming apparatus 0101 via a system bus 0212. The CPU 0201 functions as a processing unit that executes each process described below by executing programs stored in a computer-readable storage unit 0205 and loaded into a RAM (Random Access Memory) 0202. The RAM 0202 is a type of general volatile storage device directly accessible by the CPU 0201 and is used as a work area for the CPU 0201 or other temporary data storage area. The storage unit 0205 also functions as a temporary storage area and work memory during operation of the image forming apparatus. The engine I / F 0209 communicates with the printer engine 0210. The paper feed deck I / F 0204 communicates with the paper feed deck 0211. The paper feed deck 0211 functions as a processing unit that executes each process described below by collectively referring to the paper feed decks 0103, 0104, and optional deck 0105 as a hardware configuration. The UI panel 0203 is a hardware configuration of the UI panel 0102, and is a user interface for performing overall operations of the image forming apparatus 0101. In this embodiment, the UI panel 0203 is equipped with a capacitive touch panel.

[0017] The network interface (hereinafter, NW I / F) 0207 is connected to the NW I / F 0238 of the information processing device 0109 via a communication cable 0213 and is used for communication between the information processing device 0109 and the image forming device 0101. Note that in this example, the interfaces (0207, 0238) connected to the system bus (0212, 0239) are directly connected to each other, but this is not limited to this. For example, the information processing device 0109 and the image forming device 0101 may be connected via a network such as a LAN, and the connection type is not limited to this. The video I / F 0206 is connected to the video I / F 0233 via a video cable 0241 and is used for communication of image data between the information processing device 0109 and the image forming device 0101. Note that the connection interface between the information processing device 0109 and the image forming device 0101 may be a combination of the functions of the NW I / F 0238 and the video I / F 0233. The connection interface between the image forming apparatus 0101 and the information processing apparatus 0109 may be a combination of the functions of the NW I / F 0207 and the video I / F 0206 .

[0018] The accessory I / F 0208 is connected to the accessory I / F 0214 and the accessory I / F 0220 via a communication cable 0225. That is, the image forming apparatus 0101 can communicate with the inspection unit 0106 and the large-capacity stacker 0107 via the accessory I / Fs 0208, 0214, and 0220.

[0019] The CPU 0216 controls and performs calculations for each component within the inspection unit 0106 via a system bus 0219. The CPU 0216 functions as a processing unit that executes each process described below by executing programs stored in a computer-readable storage unit 0247 and loaded into a RAM 0217. The RAM 0217 is a type of general volatile storage device that can be directly accessed by the CPU 0216 and is used as a work area or other temporary data storage area for the CPU 0216. The storage unit 0247 functions as a temporary storage area and work memory during inspection device operation. The inspection device I / F 0215 is connected to the inspection device unit I / F 0231 via a communication cable 0248. That is, the inspection unit 0106 communicates with the inspection device 0108 via the inspection device I / F 0215 and the inspection device unit I / F 0231. The photographing unit 0218 has a photographing function (scanning function) equipped with, for example, a contact image sensor (hereinafter, CIS), and transmits an image generated by photographing (reading and scanning) a sheet of paper passing through the inspection unit to the inspection device 0108 via the inspection device I / F 0215. Note that the CIS equipped in the photographing unit 0218 is an example of a sensor, and may be another type of sensor such as a CCD image sensor, and the photographing method (scanning method) is not limited thereto.

[0020] The CPU 0220 controls and performs calculations for each unit in the large-capacity stacker 0107 via the system bus 0224. The CPU 0220 functions as a processing unit that executes each process described below by executing programs stored in the computer-readable storage unit 0248 and loaded into the RAM 0222. The RAM 0222 is a type of general volatile storage device that can be directly accessed by the CPU 0221, and is used as a work area for the CPU 0221 or as a temporary data storage area. The paper discharge unit 0223 monitors and controls the paper discharge operation to the main tray and top tray, and the loading status of each of the main tray and top tray.

[0021] The CPU 0226 of the inspection device 0108 controls and performs calculations for each component within the inspection device 0108 via the system bus 0230. The CPU 0226 functions as a processing unit that executes each process described below by executing programs stored in the computer-readable storage unit 0228 and loaded into the RAM 0227. The RAM 0227 is a type of general volatile storage device directly accessible by the CPU 0226 and is used as a work area or other temporary data storage area for the CPU 0226. The storage unit 0228 functions as a temporary storage area and work memory during inspection device operation. The PDL analysis unit 0229 reads PDL data, such as PDF, PostScript, or PCL, received from the client computer 0110 or the information processing device 0109 and performs interpretation processing. The display unit 0245 is, for example, a liquid crystal display connected to the inspection device, and accepts user inputs to the inspection device and displays the status of the inspection device.

[0022] The CPU 0234 of the information processing device 0109 controls and performs calculations for each unit within the information processing device 0109 via a system bus 0239. The CPU 0234 functions as a processing unit that executes each process described below by executing programs stored in a computer-readable storage unit 0236 and loaded into a RAM 0235. The RAM 0235 is a type of general volatile storage device that can be directly accessed by the CPU 0234 and is used as a work area for the CPU 0234 or other temporary data storage area. The storage unit 0236 functions as a temporary storage area and work memory when the information processing device is operating. The network interface (hereinafter referred to as NW I / F) 0237 is connected to the NW I / Fs 0232 and 0240 via a network. The information processing device 0109 communicates with the inspection device 0108 via the NW I / Fs 0237 and 0232. The information processing device 0109 also communicates with the client computer 0110 via the NW I / F 0237 and the NW I / F 0240 .

[0023] The CPU 0243 of the client computer 0110 controls each unit in the client computer 0110 and performs calculations via the system bus 0246. The CPU 0243 functions as a processing unit that executes each process described below by executing programs stored in the computer-readable storage unit 0245 and loaded into the RAM 0242. The RAM 0242 is a type of general volatile storage device that can be directly accessed by the CPU 0243, and is used as a work area for the CPU 0243 or other temporary data storage area. The storage unit 0244 functions as a temporary storage area and work memory when the client computer is operating.

[0024] FIG. 3 shows the internal configuration of the printing device 0101, inspection unit 0106, and large-capacity stacker 0107. The printing device 0101 accepts user input and displays printing and device status via a UI panel 0102. Various types of paper can be stored in the paper feed decks 0103 and 0104. Each paper feed deck can separate only the topmost sheet of paper from the stack and transport it to a paper transport path 0305. Development stations 0301 to 0304 form color images by using Y, M, C, and K color toners, respectively. The toner images formed here are primarily transferred to an intermediate transfer belt 0306. The intermediate transfer belt 0306 rotates clockwise in the figure, and the toner image is transferred to paper transported from the paper transport path 0305 at a secondary transfer position 0307. The fusing unit 0308 is equipped with a pressure roller and a heating roller, and as the paper passes between these rollers, the toner is melted and pressed to fix the toner image to the paper. After passing through the fusing unit 0308, the paper is transported to 0312 via paper transport path 0309. If further fusing and pressing is required for fusing depending on the type of paper, after passing through the fusing unit 0308, the paper is transported to the second fusing unit 0310 via the upper paper transport path, where additional fusing and pressing is performed, and then transported to 0312 via paper transport path 0311. If the image formation mode is double-sided, the paper is transported to the paper reversal path 0313, and after being reversed at 0313, is transported to the double-sided transport path 0314, where the image on the second side is transferred to the secondary transfer position 0307.

[0025] CISs 0315 and 0316 are arranged facing each other within the inspection unit 0106. CIS 0315 is a sensor for reading the top surface of the paper, and CIS 0316 is a sensor for reading the bottom surface of the paper. The inspection unit 0106 scans the paper using CISs 0315 and 0316 when the paper transported on the paper transport path 0317 reaches a predetermined position. The image generated by the scan is sent to the inspection device 0108 via the inspection device I / F 0215 and the inspection unit I / F 0231. The CPU 0226 of the inspection device 0108 determines whether the received image contains defects and notifies the inspection unit 0106 of the determination result via the inspection unit I / F 0231 and the inspection device I / F 0215. The inspection unit CPU 0216 notifies the received determination result to the large-capacity stacker 0107 via the accessory I / Fs 0214 and 0220.

[0026] The large-capacity stacker 0107 can hold a large volume of paper. The large-capacity stacker 0107 has a main tray 0324 as a tray for stacking paper. Paper that has passed through the inspection unit 0106 enters the large-capacity stacker 0107 via a paper transport path 0319. Paper that is determined to be properly printed by the inspection device 0108 is transported from the paper transport path 0319 to a paper transport path 0322 and then stacked on the main tray 0324. The large-capacity stacker 0107 also has a top tray 0320 as a paper output tray. The CPU 0221 controls the ejection of paper that has been detected as defective by the inspection device 0108 to the top tray 0320. When outputting to the top tray 0320, the paper is transported from the paper transport path 0319 to the top tray 0320 via a paper transport path 0321. Reference numeral 0323 denotes an inverting unit for inverting paper. This inverting unit 0323 is used when stacking paper on the main tray 0324. To ensure that the orientation of the incoming paper is the same as the orientation of the paper when it is loaded onto the main tray 0324, the paper is inverted once by the inverting unit 0323. When transporting paper to the top tray 0320, the paper is discharged as is without being flipped when it is loaded, so the inverting unit 0323 does not perform the inverting operation.

[0027] The following describes the processing that characterizes the present invention using flowcharts and screen examples. The image forming apparatus program associated with this flow is stored in the storage unit 0205 of the image forming apparatus 0101, read into the RAM 0202, and executed by the CPU 0201. The inspection apparatus program associated with this flow is stored in the storage unit 0228 of the inspection apparatus 0108, read into the RAM 0227, and executed by the CPU 0226. The information processing apparatus program associated with this flow is stored in the storage unit 0236 of the information processing apparatus 0109, read into the RAM 0235, and executed by the CPU 0234. The client computer program associated with this flow is stored in the storage unit 0245 of the client computer 0110, read into the RAM 0242, and executed by the CPU 0243.

[0028] The overall flow from the font registration work performed before the start of the inspection to the inspection of the image to be inspected will be explained using the flowchart in Figure 4.

[0029] First, in step S401, the user creates and registers font data to be registered. The font data to be registered is data associating character shape images with character codes required for character recognition (OCR) performed during data inspection. Here, the inspection device 0108 starts reading the font registration image, and the client computer 0110 executes a print job for font registration. In this embodiment, the print job for font registration is a job that prints a font with the same character shape and size as the font used in the printed material to be inspected, and is printed on the same paper as the printed material to be inspected. The inspection unit then reads the printed material and sends the generated image to the inspection device. The inspection device can create data associating each character image in the received image with its corresponding character code. When registering the font, the character recognition method to be applied is also determined. Details will be described later.

[0030] Next, in step S402, the user registers a reference image that will serve as a reference for inspection. First, the client computer 0110 executes a print job for registering the reference image and generates a reference image by reading the printed paper. The inspection device 0108 then reads and registers the generated reference image. Note that a RIP image generated by rasterizing the print job may be received from the information processing device 0109 or the client computer 0110 and used as the reference image.

[0031] Next, in step S403, the user sets the inspection parameters, inspection area, and inspection level, as will be described in detail later.

[0032] Next, in step S404, the printout printed by the image forming apparatus 0101 is inspected by the inspection device 0108. That is, a print job for generating the printout to be inspected is generated by the client computer 0110 and transmitted to the information processing device 0109 for management. Furthermore, when the image forming apparatus 101 executes this print job and outputs printed paper, the inspection unit 0106 detects the conveyance of the printed paper, scans the paper using the CIS 0315 and 0316, and stores the scanned image in the RAM 303 of the inspection device 0108. The inspection device compares the stored scanned image with a reference image to inspect whether the printing is correct and outputs the inspection results. The inspection is performed based on the settings specified by the user in the inspection settings. Based on the inspection results, the large-capacity stacker 0107 ejects printed paper determined to be defective to a separate tray.

[0033] Next, details of font registration in S401 will be explained using the UI diagrams of FIGS. 5 and 6 and the flowchart of FIG.

[0034] FIG. 5 shows an example of a font registration screen displayed on the UI panel 0102 and accepting a user's operation to register a font. Reference numeral 501 denotes a button for starting reading a scanned image. Reference numeral 502 denotes a character area selection button. After the user presses the character area selection button 502, the user can select a character area by clicking a frame 505 indicating a character area displayed on the scanned image with the mouse. Reference numeral 503 denotes a character area placement button. After the user presses the character area placement button 503, the user can select a character area by dragging the mouse on the preview display to place the character area. The user selects a character area to include a character string containing the characters for which font registration is desired. Reference numeral 504 denotes a preview display area in which the scanned image is previewed. Reference numeral 505 denotes a frame indicating a character area placed on the preview-displayed scanned image. Reference numeral 506 denotes a field for setting the direction of the character string in the selected character area. When the user presses button 507, individual characters are extracted from the arranged character area 505, and the screen transitions to the character extraction screen shown in Fig. 6. 508 is a completion button for completing the font registration process.

[0035] FIG. 6 shows a character segmentation screen displayed on the UI panel 0102. Reference numeral 601 denotes a screen that displays a preview of an image of a character area and the segmentation position of each character. A preview of the character area set by the user on the font registration screen is displayed, and a frame indicating the coordinates of the segmentation process result for each character is displayed on the preview. Reference numeral 602 denotes an input field for the font name of the registered font. Reference numeral 603 denotes an input field for the font size of the registered font. Reference numeral 604 denotes a text box for inputting character segmentation images segmented on a character-by-character basis from the character area and characters (character codes) to be associated with the character segmentation images. Reference numeral 605 denotes a registration button. When the user presses the registration button, the association between each character image and character code in 604, as well as the font name in 602 and the size in 603, are saved, the segmentation screen in FIG. 6 is closed, and the screen transitions to the font registration screen in FIG. 5.

[0036] 7 is a flowchart showing the processing executed by the inspection device 0108 when a font registration operation is performed on the inspection device 0108. In response to an operation on the font registration screen and character extraction screen displayed on the UI panel 0102, the CPU 0226 executes various processes for making inspection settings.

[0037] In S701, the CPU 0226 accepts an operation to start reading a scanned image from the font registration screen. In this embodiment, the operation to start reading a scanned image is the user pressing the scan image reading start button 501. When the CPU 0226 accepts the pressing of the scan image reading start button 501, it transitions to a state waiting to receive a scanned image of a printed material. Thereafter, when a print job is executed, the image scanned by the inspection unit 0106 is read into the font registration screen.

[0038] In S702, the user executes a print job for font registration on the client computer 0110. The CPU 0226 of the inspection device 0108 receives an image of the printed matter scanned by the inspection unit 0106 from the inspection unit 0106 via the inspection device I / F 0215 and the inspection unit I / F 0231. Thereafter, the CPU 0226 displays the scanned image on the preview display screen 504 of the font registration screen.

[0039] In step S703, the CPU 0226 ends the waiting state for receiving the scanned image of the printed matter.

[0040] In step S704, the CPU 0226 accepts a character area setting operation from the font registration screen. The user sets the character area on the preview of the loaded image using the character area selection button 502, the character area placement button 503, and the character string direction setting field 506.

[0041] In S705, the CPU 0226 accepts a character segmentation operation from the font registration screen. In this embodiment, the character segmentation operation is the user pressing button 507, which starts character segmentation. Upon accepting the pressing of button 507, which starts character segmentation, the CPU 0226 executes segmentation of individual characters from within the set character region and transitions to a character segmentation screen. The character segmentation process is, for example, a process of calculating a pixel value histogram for an image of the character region and segmenting an area where this pixel value histogram stands out as a character segmentation image. This character segmentation method is one example, and other methods may be used to extract each character image.

[0042] In S706, the CPU 0226 accepts an input operation of characters (character codes) to be associated with each character cut-out image cut out in S705 on the character cut-out screen. In this embodiment, the user inputs characters (character codes) in the text box 604.

[0043] In step S707, the CPU 0226 accepts an input operation for a font name and a font size on the character extraction screen. The input operation for a font name and a font size is an input operation by the user in the input field 602 for the font name of the registered font and the input field 603 for the font size.

[0044] In S708, the CPU 0226 determines whether to perform character recognition with an emphasis on accuracy or speed when using the currently registered font. In this embodiment, if the font size received in S707 is smaller than a specified value, the CPU 0226 determines to perform character recognition with an emphasis on accuracy; otherwise, the CPU 0226 determines to perform character recognition with an emphasis on speed. This is because characters with a larger font size tend to have better recognition accuracy even when using character recognition with an emphasis on speed. Note that the method for determining the character recognition method to be performed is merely an example, and various methods are possible in addition to those described in this embodiment. For example, the method may be determined using the resolution of the extracted character image, the number of registered characters, the character color, the font name, etc. Making this determination during the font registration process rather than during the inspection process can reduce overhead during the inspection process. Furthermore, if initialization processing corresponding to the determined character recognition method is also performed at this time, overhead during the inspection process can be further reduced. An example of initialization processing corresponding to the character recognition method is instance generation processing.

[0045] In step S709, the CPU 0226 calculates parameters to be used in preprocessing before character recognition using the currently registered font. The parameters used in preprocessing are, for example, binarization thresholds used when binarizing a scanned image. By calculating these parameters during the font registration process rather than during the inspection process, overhead during the inspection process can be reduced.

[0046] In step S710, the CPU 0226 accepts a registration operation from the character segmentation screen. In this embodiment, the registration operation is the user pressing the registration button 605. The CPU 0226 then stores the font name, font size, character segmentation image, associated character code, character recognition processing method to be used, and preprocessing parameters in the storage unit 0228 as registered font data, and terminates the font registration process. In other words, the font data is registered in association with the character recognition processing method and preprocessing parameters to be applied.

[0047] Next, the details of the inspection settings will be explained using the UI diagrams in Fig. 8 and Fig. 9, and the flowchart in Fig. 10. The inspection settings start by selecting the reference image (image that serves as a reference) registered in the reference registration.

[0048] 8 and 9 are examples of an inspection setting screen that is displayed on the UI panel 0102 and that accepts an inspection setting execution operation from the user. On the inspection setting screen, the user specifies the position of the inspection area on the preview-displayed reference image, and further, sets each inspection area individually.

[0049] Reference numeral 801 denotes a preview display screen on which a reference image is displayed as a preview. If the reference image is generated based on a multi-page print job, the reference image for each page can be displayed sequentially by switching the reference image displayed as a preview.

[0050] Reference numerals 802 and 803 denote frames showing inspection areas placed on the preview. Inspection areas are placed using an inspection area placement button 805, and the user can change the size and position by dragging the mouse. Reference numeral 802 shows an example of a pattern inspection area. Reference numeral 803 shows an example of a character string inspection area.

[0051] An inspection area selection button 804 is provided. After the user presses the inspection area selection button 804, the user can select an inspection area by clicking frames 802 and 803 indicating the inspection area with the mouse.

[0052] An inspection area placement button 805 is referenced. After the user presses the inspection area placement button 805, the user selects the type of inspection area from the displayed pull-down menu, and then selects the area on the preview display that the user wants to specify as the inspection area by dragging the mouse, thereby accepting the placement operation of the inspection area.

[0053] 806 is a setting item for selecting data for verification testing using the file selection method. Verification testing data is a reference CSV file for data testing that is verified when conducting a data test. The reference CSV file is a file that the user must prepare in advance, and it is a file that lists the correct strings for string testing and the correct strings when decoded for barcode testing. In other words, when a data test is performed to verify the contents of a scanned string or the decoded contents of a code image (barcode or 2D code), the OCR results of the string image in the string testing area and the string resulting from decoding the code image are verified against the correct strings listed in the reference CSV file.

[0054] Reference numeral 807 denotes a setting item for the selected area, and individual setting values ​​for the inspection area selected after pressing the inspection area selection button 505 are displayed.

[0055] 808 is a setting item for the page range. When the user presses each button, the operation to specify the range of pages on which inspection will be performed by the selected inspection area is accepted. If nothing is selected, the selected inspection area will be placed only on the page currently displayed on the preview display screen. If "Same side as current page" is selected, the selected inspection area will also be placed on other pages on the same side (front or back) depending on whether the selected inspection area is placed on the front or back of the sheet. If "All pages" is selected, the selected inspection area will be placed on all pages, regardless of whether they are on the front or back.

[0056] 809 in FIG. 8 and 901 in FIG. 9 are setting items for each type of inspection area, and setting items according to the type of inspection area selected by the inspection area selection button 804 are displayed.

[0057] Reference numeral 809 in FIG. 8 denotes setting items for pattern inspection that are displayed when the pattern inspection area 802 is selected. The setting items for pattern inspection include items such as what type of defects are inspected when inspecting printed matter and the level at which minute defects are detected. The setting items for pattern inspection include items such as what type of defects are inspected when inspecting printed matter and the level at which minute defects are detected. Inspection items include, for example, round defects (hereinafter referred to as "dots") and linear defects (hereinafter referred to as "streaks"). There are five inspection levels, for example, from level 1 to level 5, with level 5 being able to detect thinner and smaller defects than level 1. In addition, a level can be set for each inspection item, such as inspection level 5 for dots and inspection level 4 for streaks.

[0058] Reference numeral 901 in FIG. 9 denotes the setting items for the string inspection that are displayed when the string inspection area 803 is selected. For each inspection area, you can set the angle of the inspection area, the font of the string, whether to perform a comparison inspection, and which column in the reference CSV to compare with if a comparison inspection is performed. An item for selecting the font of the string to be used in the inspection area is displayed, and the font selection from the user is accepted. A font that was registered in S401 can be selected, and the information of the selected font can be associated with the desired inspection area and saved.

[0059] Reference numeral 810 denotes a test setting completion button. When the user presses the completion button, the test setting is completed, the settings are saved in the memory unit 0228, and the test setting process ends. If there is an inconsistency in the settings, the test setting completion button 810 may be disabled so that it cannot be pressed. An example of a setting inconsistency is when an inspection area exists for performing a verification test, but the setting item 806 for the data for the verification test has not been set. Reference numeral 811 denotes a test setting cancellation button. When the user presses this button, the settings are discarded and the test setting process ends.

[0060] 10 is a diagram showing the processing in the inspection device 0108 when an inspection setting start operation is performed on the inspection device 0108. In response to an operation from the inspection setting screen displayed on the UI panel 0102, the CPU 0226 of the inspection device 0108 executes various processes for setting up the inspection.

[0061] In step S1001, the CPU 0226 accepts a setting operation for the data of the verification test from the test setting screen. In this embodiment, the setting operation for the data of the verification test is an operation of the setting item 507 for the data of the verification test by the user.

[0062] In step S1002, the CPU 0226 accepts an operation to arrange the inspection area from the inspection setting screen. In this embodiment, the operation to arrange the inspection area is an operation of the inspection area arrangement button 805 by the user.

[0063] In S1003, the CPU 0226 accepts an inspection area selection operation from the inspection setting screen. In this embodiment, the inspection area selection operation is an operation in which the user presses the inspection area selection button 804 to select one of the inspection areas arranged in the preview display area.

[0064] In S1004, the CPU 0226 accepts a setting operation for each type of inspection area from the inspection setting screen. In this embodiment, the setting operation for each inspection area is an operation by the user to set the setting items for each type of inspection area (setting operations for each setting item 809 in FIG. 8 and 901 in FIG. 9).

[0065] In S1005, the CPU 0226 determines whether the user has pressed the Complete button 810, which instructs completion of the test settings, and if the Complete button has been pressed, proceeds to S1006. If the test settings are not complete, return to S1003 and the user continues the test settings.

[0066] In S1006, the CPU 0226 stores the settings in the storage unit 0228, and ends the test setting process.

[0067] Next, the details of the inspection will be explained using the flowchart in Fig. 11. The CPU 0226 of the inspection device 0108 executes various processes for the inspection.

[0068] In step S1101, the CPU 0226 loads the inspection settings from the storage unit 0228 into the RAM 0227 and enters a state of waiting for reception of a scanned image of a printed material to be inspected. After that, when a print job is executed, the scanned image transmitted from the inspection unit 0106 can be processed as an inspection target.

[0069] In step S1102, the user instructs the client computer 0110 to execute a print job to be inspected, and the image forming device executes printing based on the print job. The CPU 0226 receives an image generated by scanning the printout to be inspected by the inspection unit 0106 via the inspection device I / F 0215 and the inspection unit I / F 0231.

[0070] In S1103, the CPU 0226 cuts out and acquires an image of the inspection area specified by the inspection settings read in S1101 from the scanned image received from the inspection unit 0106 in S1102.

[0071] In S1104, the CPU 0226 determines whether the inspection area acquired in S1103 is an area set for pattern inspection or for character string inspection in the inspection settings read in S1101. If it is a pattern inspection area, the process proceeds to S1105, and if it is a character string inspection area, the process proceeds to S1106.

[0072] In S1105, the CPU 0226 compares the image of the inspection area acquired in S1103 with a reference image of the image to be printed in that area to inspect whether there are any defects in the printed image. If a difference is detected, it is determined that there is a defect in the printed matter and the inspection result of that inspection area is NG, but if no difference is detected (or the difference is within the allowable range), the inspection result is OK.

[0073] In S1106, the CPU 0226 performs preprocessing such as background removal and binarization on the inspection area where the character string inspection is performed. Font information is set for the inspection area for character string inspection, as described in FIG. 9. Therefore, in this preprocessing, the preprocessing parameters to be used can be determined based on the font information set for the inspection area and the preprocessing parameters that were previously saved in association with the registered font data in S709 of FIG. 7. This eliminates the need to analyze the image and calculate the preprocessing parameters when performing the inspection, thereby reducing overhead during the inspection process.

[0074] In S1107, the CPU 0226 determines whether the character recognition processing method previously stored in association with the registered font data prioritizes speed or accuracy. Here, the CPU 0226 determines whether to apply character recognition processing that prioritizes speed or accuracy based on the font information previously set for the inspection area in FIG. 9 and the character recognition processing method information previously associated with the registered font data in S708 of FIG. 7. Therefore, it is not necessary to analyze the image of the inspection area to determine the character recognition processing method, thereby reducing overhead during inspection processing. If speed is prioritized, proceed to S1108; if accuracy is prioritized, proceed to S1109.

[0075] In step S1108, the CPU 0226 executes speed-oriented character recognition processing on the image of the inspection area using registered font data set for the inspection area.

[0076] In step S1109, the CPU 0226 executes character recognition processing with emphasis on accuracy on the image of the inspection area using registered font data set for the inspection area.

[0077] In S1110, the CPU 0226 compares the character string described in the reference CSV file with the character recognition result obtained in S1108 or S1109. If the comparison result shows a mismatch, the inspection result for the inspection area is determined to be NG, and if the comparison result shows a match, the inspection result for the inspection area is determined to be OK.

[0078] In step S1111, the CPU 0226 determines whether the inspection of the inspection area specified in the inspection setting has been completed. If completed, the process proceeds to step S1112, and if not completed, the process proceeds to step S1103.

[0079] In step S1112, the CPU 0226 determines the result of the inspection. If the inspection of all inspection areas in the scanned image is successful, the process proceeds to step S1113, and if the inspection of even one inspection area is unsuccessful, the process proceeds to step S1114.

[0080] In step S1113, the CPU 0226 instructs the large-capacity stacker 0107 to output the printouts that passed inspection onto the main tray of the paper discharge unit 0223 of the large-capacity stacker 0107.

[0081] In step S1114, the CPU 0226 instructs the large-capacity stacker 0107 to output the printouts that have failed the inspection onto the top tray of the paper discharge unit 0223 of the large-capacity stacker 0107.

[0082] In step S1115, the CPU 0226 determines whether inspection of all prints to be inspected has been completed. If not, the process proceeds to step S1102, and if completed, the process proceeds to step S1116.

[0083] In step S1116, the CPU 0226 ends the waiting state for receiving the scanned image of the printed matter, and then ends the inspection process.

[0084] As described above, according to this embodiment, when font data is registered, information on the character recognition process and preprocessing to be applied to the character image of the font size to be registered are associated with the font data and registered (S708 to S710 in FIG. 7). Furthermore, when an inspection area for a character string is set, information on the font to be printed in the inspection area is set (901 in FIG. 9). This allows for easy determination of the preprocessing and character recognition process methods to be applied when scanning a printed material to inspect the print quality, thereby improving inspection speed and accuracy. Furthermore, overhead can be further reduced by individually generating and initializing instances according to the character recognition method and parameter combination prior to inspection.

[0085] Second Embodiment In the second embodiment, an example in which the character recognition processing to be applied is also determined and saved when the inspection area is set will be described with reference to Fig. 12. Note that the description will omit parts common to Fig. 10 of the first embodiment.

[0086] 12 is a diagram showing the processing of the second embodiment in the inspection device 0108 when an inspection setting start operation is performed on the inspection device 0108. In response to an operation from the inspection setting screen displayed on the UI panel 0102, the CPU 0226 executes various processes for setting up the inspection.

[0087] The processes in S1001 to S1004 are the same as those explained above with reference to FIG. 10, and therefore detailed explanations will be omitted.

[0088] In S1201, the CPU 0226 determines whether the type of the inspection area selected in S1003 is a character string inspection area, and if it is a character string inspection area, proceeds to S1202, and if it is not a character string inspection area, proceeds to S1005.

[0089] In S1202, the CPU 0226 determines whether the character recognition process to be applied to the currently set character string inspection area is character recognition process that prioritizes accuracy or character recognition process that prioritizes speed. In this embodiment, if the size of the characters (or the number of pixels of the characters) printed in the character string inspection area set on the reference image is smaller than a specified value, it determines to perform character recognition process that prioritizes accuracy, and if the size is equal to or greater than the specified value, it determines to perform character recognition process that prioritizes speed. The method of determining the character recognition process to be performed is just one example, and there are various other methods besides the one shown in this embodiment. By determining this character recognition process while setting the inspection area, it is possible to reduce overhead during subsequent inspection processing. The determined character recognition method is saved in the memory unit 0228 as an inspection setting in S1006.

[0090] In S1203, the CPU 0226 calculates parameters to be used in preprocessing when performing character recognition on the currently set character string inspection area. Examples of parameters to be used in preprocessing include the brightness of the background part in the scanned image and a binarization threshold. By performing this calculation while the inspection area is being set rather than during the inspection process, it is possible to reduce overhead during the subsequent inspection process. Furthermore, by performing initialization processing according to the determined character recognition process at this timing, it is possible to reduce overhead during the inspection process. The calculated parameters to be used in preprocessing are saved in the memory unit 0228 as inspection settings in S1006.

[0091] According to the present embodiment, by following the above procedure, the character recognition process is determined and initialization processing according to the character recognition process is performed prior to testing, thereby improving overhead during testing and improving testing speed and accuracy.

[0092] Other Examples The present invention can also be realized by executing the following process: software (program) that realizes the functions of the above-described embodiments is supplied to a system or device via a network or a computer-readable storage medium, and the computer (or CPU, MPU, etc.) of the system or device executes the program.

Claims

1. An inspection device having an inspection means for inspecting a read image obtained by reading an image on a recording material conveyed from a conveying means that receives the recording material on which an image has been printed from a printing device that has printed the image on the recording material, the read image being read by a reading unit, the read image being read by a reading unit, the inspection device comprising: a registration means for registering a font and a character recognition processing method in association with each other before the inspection is performed by the inspection means; a setting means for setting an inspection area in which a character string is inspected and a font to be used in the inspection area; The inspection means determines a character recognition processing method to be applied to the inspection area based on the font used in the inspection area set by the setting means and the character recognition processing method associated with the font by the registration means, and performs character recognition processing on an image corresponding to the inspection area in the read image using the determined character recognition processing method. An inspection device characterized by:

2. 2. The inspection device according to claim 1, wherein the character recognition processing method registered by the registration means in association with the font is either character recognition processing that emphasizes accuracy or character recognition processing that emphasizes speed.

3. the registration means registers the font, the character recognition processing method, and information on pre-processing executed before the character recognition processing in association with each other; The inspection device described in claim 1, characterized in that the inspection means performs pre-processing associated with the font on an image corresponding to the inspection area in the read image based on the font used in the inspection area set by the setting means, the character recognition processing method associated with the font by the registration means, and the pre-processing information, and uses the determined character recognition processing method to perform character recognition processing on the image corresponding to the inspection area in the read image after the pre-processing has been performed.

4. An inspection device as described in Claim 3, characterized in that the pre-processing information is information regarding base treatment.

5. An inspection device as described in Claim 3, characterized in that the preprocessing information is a parameter used when binarizing the read image.

6. 6. The inspection device according to claim 1, wherein the inspection means further executes an inspection to compare the result of the character recognition processing with a correct character string.

7. An inspection device having an inspection means for inspecting a read image obtained by a reading unit reading the image on a recording material conveyed from a conveying means that receives and conveys a recording material on which an image has been printed from a printing device that has printed the image on the recording material, a setting means for setting an inspection area in which a character string is to be inspected in the displayed reference image based on a user's instruction, and for setting a character recognition processing method to be applied to the inspection area based on the character size within the set inspection area before the inspection is performed by the inspection means; The inspection device is characterized in that the inspection means performs character recognition processing on an image corresponding to the inspection area in the read image using the character recognition processing method set by the setting means.

8. An inspection device as described in Claim 7, characterized in that the character recognition processing method registered in association with a font by the setting means is either character recognition processing that emphasizes accuracy or character recognition processing that emphasizes speed.

9. The setting means registers the character size, the character recognition processing method, and information on pre-processing executed before the character recognition processing in association with each other; The inspection device described in claim 7, characterized in that the inspection means performs preprocessing associated with the character size on an image corresponding to the inspection area in the read image based on the character size used in the inspection area set by the setting means, the character recognition processing method associated with the character size used in the inspection area, and the preprocessing information, and uses the set character recognition processing method to perform character recognition processing on the image corresponding to the inspection area in the read image after the preprocessing has been performed.

10. An inspection device as described in Claim 9, characterized in that the pre-processing information is information regarding base processing.

11. An inspection device as described in Claim 9, characterized in that the pre-processing information is a parameter used when binarizing the read image.

12. An inspection device described in any one of claims 7 to 11, characterized in that the inspection means further performs an inspection to compare the result of the character recognition processing with a correct string of characters.

13. A program for causing a computer to function as the inspection device according to any one of claims 1 to 12.

14. A control method for an inspection device having an inspection means for inspecting a read image obtained by a reading unit reading the image on a recording material conveyed from a conveying means that receives and conveys a recording material on which an image has been printed from a printing device that has printed the image on the recording material, the method comprising: a registration step of registering a font and a character recognition processing method in association with each other before the execution of the inspection; a setting step of setting an inspection area in which a character string is inspected and a font to be used in the inspection area; an inspection step of determining a character recognition processing method to be applied to the inspection area based on the font used in the inspection area set in the setting step and the character recognition processing method associated with the font in the registration step, and performing character recognition processing on an image in the read image corresponding to the inspection area using the determined character recognition processing method; A control method for an inspection apparatus, comprising:

15. A control method for an inspection device that inspects a read image obtained by a reading unit reading an image on a recording material that has been conveyed from a conveying means that receives and conveys a recording material on which an image has been printed from a printing device that has printed the image on the recording material, the method comprising: a step of setting an inspection area for inspecting a character string based on a user's instruction in a reference image displayed before the inspection is performed, and setting a character recognition processing method to be applied to the inspection area based on the size of the characters in the set inspection area; performing character recognition processing on an image corresponding to the inspection area in the read image using the set character recognition processing method; A control method for an inspection apparatus, comprising:

16. 2. The inspection device according to claim 1, wherein the period before the inspection is performed is before the read image is obtained by the reading unit.

17. 8. The inspection device according to claim 7, wherein the period before the inspection is performed is before the read image is obtained by the reading unit.

Images