Inspection system

Abstract

The objective is to provide an inspection system, a control method for the inspection system, and a program that can quickly initiate the inspection of printed materials. [Solution] The inspection system 1000 performs inspection on printed materials. This inspection system 1000 includes data acquisition means (data control unit 421, etc.) that acquires print data that becomes printed material through printing, a first process that processes the print data to become reference image data that serves as the basis for inspection, and a second process that, during inspection, compares scanned image data of the printed material acquired by reading the printed material on which the print data has been printed with the reference image data and performs inspection. These processes are executed in parallel by processing means (image processing unit 258, inspection processing unit 278, etc.).

Description

Technical Field

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

Background Art

[0002] Printed matter obtained by printing on a printing device may be inspected for quality. In this case, in an inspection device, a read image of the printed matter read by a scanner or the like is compared with a reference image, and based on the comparison result, the quality of the printed matter is inspected. As the reference image, for example, a RIP image generated before printing on a printing device or a RIP image generated by RIP software is used. For example, when there is dirt on the printed matter, a portion corresponding to this dirt is also reflected in the read image of the printed matter. And in quality inspection, a read image including a portion corresponding to dirt is compared with a RIP image not including a portion corresponding to dirt, and the inspection result of the printed matter becomes defective. Also, the reference image needs to be registered in the inspection device at the time of quality inspection. For example, Patent Document 1 describes a device that executes a reference registration job for registering a reference image prior to quality inspection. The device described in this Patent Document 1 registers reference images of all pages included in a printing job.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when using the apparatus described in Patent Document 1, two job submissions are required: one for registering a reference image and another for quality inspection. Then, the RIP processing for the job to register the reference image (hereinafter referred to as "pre-RIP processing") and the RIP processing for the job to inspect the quality (hereinafter referred to as "post-RIP processing") are executed in sequence. For users who wish to perform quality inspection, there was a problem in that the time spent on pre-RIP processing was perceived as waiting time until post-RIP processing began. A shorter waiting time is preferable.

[0005] This invention has been made in view of the above-mentioned problems. The object of this invention is to provide an inspection system, a control method for the inspection system, and a program that can quickly start the inspection of printed materials. [Means for solving the problem]

[0006] To achieve the above objective, the present invention provides an inspection system for inspecting printed materials, comprising: data acquisition means for acquiring print data that becomes the printed material through printing; a first process for processing the print data to be used as reference image data for the inspection; and a second process for performing, in parallel, scanning image data of the printed material acquired by reading the printed material on which the print data has been printed, and comparing the scan image data of the printed material with the reference image data for inspection. [Effects of the Invention]

[0007] According to the present invention, the inspection of printed materials can be started quickly. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram showing the overall configuration of the inspection system according to the first embodiment. [Figure 2] This is a block diagram showing the hardware configuration of an image forming apparatus, inspection unit, high-capacity stacker, inspection apparatus, information processing apparatus, client PC, and reference image generation apparatus. [Figure 3] This is a schematic diagram showing the internal configuration of the image forming apparatus, inspection unit, and large-capacity stacker. [Figure 4] This is a block diagram showing the functional configuration of the CPU in an information processing device, an image forming apparatus, a reference image generation apparatus, and an inspection apparatus. [Figure 5] This figure shows an example of information regarding image assignment. [Figure 6] This is a flowchart showing the processing performed by the image forming apparatus (communication decision processing with respect to the reference image generation apparatus). [Figure 7] This screen is used to specify the inspection mode in the job properties of the information processing device. [Figure 8] This is a flowchart showing the processes (job processing) performed by the image forming apparatus. [Figure 9A] This flowchart shows the processing performed by the reference image generation device (synchronization processing with the image forming apparatus). [Figure 9B] This is a flowchart showing the process performed by the reference image generation device (the process of transmitting reference images to the inspection device). [Figure 9C] This is a flowchart showing the process (transmission of image assignment information) performed by the image forming apparatus. [Figure 10] This is a flowchart showing the processes (inspection processes) performed by the inspection device. [Figure 11] This is a flowchart showing the processes performed between an information processing device, an image forming apparatus, a reference image generation apparatus, an inspection unit, and an inspection apparatus. [Figure 12] This is a flowchart showing the process performed by the inspection apparatus according to the second embodiment. [Figure 13] This diagram shows the screen displayed on the UI panel of the inspection device. [Figure 14] This diagram shows the screen displayed on the UI panel of the inspection device. [Figure 15] This flowchart shows the process (with variations) performed by the inspection device. [Figure 16]It is a flowchart showing the processing executed by the inspection apparatus according to the third embodiment. [Figure 17] It is a flowchart showing the processing (modified example) executed by the inspection apparatus. [Figure 18] It is a flowchart showing the processing (job processing) executed by the image forming apparatus according to the fourth embodiment.

Modes for Carrying Out the Invention

[0009] Hereinafter, each embodiment of the present invention will be described in detail with reference to the drawings. However, the configurations described in the following embodiments are merely examples, and the scope of the present invention is not limited by the configurations described in each embodiment. For example, each part constituting the present invention can be replaced with any configuration that can exhibit the same function. Also, an arbitrary component may be added. Further, any two or more configurations (features) among the embodiments can be combined.

[0010] <First Embodiment> The first embodiment will be described below with reference to Figures 1 to 11. Figure 1 is a schematic diagram showing the overall configuration of the inspection system according to the first embodiment. The inspection system 1000 shown in Figure 1 is a system for inspecting printed materials. The printed material is not particularly limited and may be, for example, a booklet with multiple pages, a single sheet of printed material, etc. The inspection system 1000 includes an image forming apparatus 101, an inspection unit 106, a large-capacity stacker 107, an inspection device 108, an information processing device 109, a client PC 110, and a reference image generation device 111. The information processing device 109 and the client PC 110 are communicated via a network 121. The information processing device 109 and the reference image generation device 111 are communicated via a network 122. The image forming apparatus 101 and the reference image generation device 111 are communicated via a network 123. The inspection device 108 and the reference image generation device 111 are communicated via a network 124. The inspection device 108 and the inspection unit 106 are connected via a communication cable 125 for communication. The client PC 110, the information processing device 109, and the inspection device 108 may also be connected via a communication cable for communication with the image forming apparatus 101. The image forming apparatus 101 includes a UI panel 102, a paper feed deck 103, a paper feed deck 104, and an optional deck 105. The UI panel 102 has a function for receiving user operations and a function for displaying a screen. Printing paper (hereinafter sometimes simply referred to as "paper") is stored in the paper feed decks 103 and 104, respectively. The optional deck 105 has three paper feed decks, each storing printing paper. The image forming apparatus 101 performs print output based on various input data, such as print data sent from the client PC 110 or the information processing device 109. The image forming apparatus 101 is not particularly limited; for example, a multi-function peripheral (MFP) can be used. Furthermore, the image forming apparatus 101 may incorporate a stapler, folding machine, binding machine, etc.

[0011] The image forming apparatus 101 incorporates an inspection unit 106 and a high-capacity stacker 107, and they are connected to each other via a communication cable which is an internal bus so as to be communicable with each other. The inspection unit 106 receives the printed matter output from the image forming apparatus 101. Then, the inspection unit 106 acquires image data for inspecting the presence or absence of abnormal images with respect to the printed matter. An "abnormal image" refers to an image that degrades the quality of the printed matter. The abnormal images are not particularly limited, and for example, round abnormal images (dots) generated by the adhesion of toner to unintended locations during printing, linear abnormal images (streaks) with color missing generated by insufficient adhesion of toner to intended locations, etc. may be mentioned. The image data acquired by the inspection unit 106 is transferred to the inspection apparatus 108 via the communication cable 125. The inspection apparatus 108 inspects the presence or absence of abnormal images in the printed matter based on the image data from the inspection unit 106. This inspection result is transmitted to the inspection unit 106. Note that in this embodiment, the inspection is performed by the inspection apparatus 108, but it is not limited thereto, and for example, it may be performed by an in-line inspection machine that consistently performs image formation, inspection, post-processing, and paper discharge. The high-capacity stacker 107 has a main tray and a top tray. Thousands of sheets of printing paper can be stacked in the main tray. Also, the high-capacity stacker 107 can receive the output paper inspected by the inspection unit 106 and switch the paper discharge destination based on the inspection result of the inspection unit 106.

[0012] The reference image generation device 111 generates a reference image (reference image data) based on the RIP image received from the information processing device 109. The reference image generation device 111 also has the function of receiving image data from the information processing device 109 via the video cable 257 (see Figure 2) and the function of transmitting image data to the image forming apparatus 101 via the video cable 215 (see Figure 2) (branching function). The "branching function" is a function that branches the destination of the image data to two destinations. One of the two destinations (hereinafter referred to as the "first destination") is the data control unit 421 (data acquisition means) of the image forming apparatus 101. The other destination (hereinafter referred to as the "second destination") is the image processing unit 258 (data acquisition means) of the reference image generation device 111. Image data can be acquired at both the first and second destinations (data acquisition process). For print jobs, the client PC 110 generates a print job. This print job is transmitted to the information processing device 109 via the network 121 and managed by the information processing device 109. The print job is then transmitted from the information processing device 109 to the image forming apparatus 101 via the network 122, the reference image generation device 111, and the network 123 in that order. The image forming apparatus 101 performs the printing process on paper based on the print job. Alternatively, the print job may be generated in the information processing device 109 and then managed by the image forming apparatus 101.

[0013] Figure 2 is a block diagram showing the hardware configuration of the image forming apparatus, inspection unit, large-capacity stacker, inspection device, information processing device, client PC, and reference image generation device. As shown in Figure 2, the image forming apparatus 101 has a CPU 201, RAM 202, UI panel (notification means) 203, paper feed deck I / F 204, and storage unit 205. The image forming apparatus 101 also has a video I / F 206, NW_I / F (network interface) 207, accessory I / F 208, engine I / F 209, paper feed deck 211, and printer engine (printing means) 210. These hardware components of the image forming apparatus 101 are connected to each other via a system bus 212 so that they can communicate with one another. The CPU 201 performs control and calculations in each part of the image forming apparatus 101. The CPU 201 executes programs stored in the storage unit 205 and loaded into the RAM 202. These programs include, for example, control programs (programs) that cause the computer to execute each process (control method of the inspection system). This control program is not limited to being stored in the image forming apparatus 101; it may also be stored in other devices, or distributed across multiple devices. RAM 202 is a type of volatile memory that can be directly accessed from the CPU 201. RAM 202 is also used as the work area or other temporary data storage area of ​​the CPU 201. The storage unit 205 functions as a temporary storage area and work memory during the operation of the image forming apparatus 101.

[0014] The engine I / F 209 communicates with and controls the printer engine 210. The paper feed deck I / F 204 communicates with and controls the paper feed deck 211. The paper feed deck 211 consists of paper feed deck 103, paper feed deck 104, and option deck 105. The UI panel 203 is included in the UI panel 102 and is a user interface for general operation of the image forming apparatus 101. In this embodiment, the UI panel 203 has a capacitive touch panel. The NW_I / F 207 is connected to the NW_I / F 254 of the reference image generation device 111 via the network 122 and performs communication between the reference image generation device 111 and the image forming apparatus 101. The NW_I / F 207 is also connected to the NW_I / F 246 of the information processing device 109 via the networks 122 and 123 and performs communication between the information processing device 109 and the image forming apparatus 101. Furthermore, NW_I / F207 is connected to NW_I / F276 of the inspection device 108 via networks 122 and 124 to facilitate communication between the inspection device 108 and the image forming apparatus 101. In this embodiment, interfaces connected to system bus 212 and system bus 248 are directly connected to each other, but this is not limited to this; for example, the information processing device 109 and the image forming apparatus 101 may be connected via a network or the like.

[0015] The video I / F 206 is connected to the video I / F 255 via the video cable 215 and facilitates the communication of image data between the image forming apparatus 101 and the reference image generation device 111. The connection interface between the information processing device 109 and the reference image generation device 111 may also be an interface that has the functions of both the NW_I / F 246 and the video I / F 245. Furthermore, the connection interface between the image forming apparatus 101 and the reference image generation device 111 may also be an interface that has the functions of both the NW_I / F 207 and the video I / F 206. Additionally, the connection interface between the information processing device 109 and the image forming apparatus 101 in the reference image generation device 111 may also be an interface that has the functions of both the NW_I / F 254 and the video I / F 255. The accessory I / F 208 is connected to the accessory I / F 221 and the accessory I / F 231 via cable 213.

[0016] The inspection unit 106 includes an accessory I / F 221, an inspection device I / F 222, a CPU 223, RAM 224, an imaging unit (reading means) 225, and a storage unit 226. These hardware components are connected to each other via a system bus 227 for communication. The CPU 223 loads the program stored in the storage unit 226 into the RAM 224. The CPU 223 then runs the program to perform control and calculations in each part of the inspection unit 106. The RAM 224 is a type of volatile memory that can be directly accessed from the CPU 223. The RAM 224 is also used as the CPU 223's work area or other temporary data storage area. The storage unit 226 functions as a temporary storage area and work memory during the operation of the inspection unit 106. The inspection device I / F 222 is connected to the inspection unit I / F 275 via a communication cable 125. The imaging unit 225 has an imaging function, for example, equipped with a conduct image sensor (hereinafter referred to as "CIS"). The imaging unit 225 photographs the printed paper as it passes through the inspection unit 106. This captured image is transmitted to the inspection device 108 via the inspection device I / F 222. The purpose of transmitting the captured image is for the inspection of the printed material by the inspection device 108. In addition to the CIS, the imaging unit 225 may use other types of sensors, such as a CCD image sensor.

[0017] The high-capacity stacker 107 includes an accessory interface 231, a CPU 232, RAM 233, a paper output unit 234, and a storage unit 235. These hardware components are connected to each other via a system bus 236 for communication. The CPU 232 loads programs stored in the storage unit 235 into the RAM 233. The CPU 232 then runs the programs to perform control and calculations in each part of the high-capacity stacker 107. The RAM 233 is a type of volatile memory that can be directly accessed by the CPU 232. The RAM 233 is also used as the CPU 232's work area or other temporary data storage area. The storage unit 235 functions as a temporary storage area and work memory during the operation of the high-capacity stacker 107. The paper output unit 234 controls the paper output operation to the main tray and top tray, and monitors the stacking status of the main tray and top tray.

[0018] The inspection device 108 includes a CPU 271, RAM (storage medium) 272, a memory unit 273, and a UI panel (notification means) 274. The inspection device 108 also includes an inspection unit I / F 275, an NW_I / F 276, and an inspection processing unit 278. These hardware components of the inspection device 108 are connected to each other via a system bus 277 for communication. The CPU 271 loads programs stored in the memory unit 273 into the RAM 272. The CPU 271 then runs the programs to perform control and calculations in various parts of the inspection device 108. The RAM 272 is a type of volatile memory device directly accessible from the CPU 271. The RAM 272 is also used as the CPU 271's work area or other temporary data storage area. The memory unit 273 functions as a temporary storage area and work memory during the operation of the inspection device 108. The UI panel 274 has a liquid crystal display and accepts user input to the inspection device 108 or displays the status of the inspection device 108. NW_I / F276 is connected to NW_I / F254 of the reference image generation device 111 via network 124, and communicates between the reference image generation device 111 and the inspection device 108. The inspection processing unit 278 inspects the printed material for defects.

[0019] The information processing device 109 includes a CPU 241, RAM 242, UI panel 243, storage unit 244, video interface 245, network interface 246, and network interface 247. These hardware components are connected to each other via a system bus 248 for communication. The CPU 241 loads programs stored in the storage unit 244 into the RAM 242. The CPU 241 then runs the programs to control and perform calculations in various parts of the information processing device 109. The RAM 242 is a type of volatile storage device directly accessible from the CPU 241. The RAM 242 is also used as the CPU 241's work area or other temporary data storage area. The storage unit 244 functions as a temporary storage area and work memory during the operation of the information processing device 109. The network interface 247 is connected to the network interface 264 via the network 121. The network interface 247 also receives instructions for paper generation, print job execution, etc., via the UI panel 243. The video interface 245 is connected to the video interface 255 via the video cable 257 to facilitate the communication of image data between the information processing device 109 and the reference image generation device 111.

[0020] The client PC 110 has a CPU 261, RAM 262, memory unit 263, and NW_I / F 264, and these hardware components are connected to each other via a system bus 265 so that they can communicate with one another. The CPU 261 loads programs stored in the memory unit 263 into the RAM 262. The CPU 261 then runs the programs to perform control and calculations in various parts of the client PC 110. The RAM 262 is a type of volatile memory that can be directly accessed by the CPU 261. The RAM 262 is also used as the CPU 261's work area or other temporary data storage area. The memory unit 263 functions as the client PC 110's temporary storage area and work memory.

[0021] The reference image generation device 111 includes a CPU 251, RAM (storage medium) 252, a memory unit 253, an NW_I / F 254, a video I / F 255, and an image processing unit 258. These hardware components are connected to each other via a system bus 256 for communication. The CPU 251 loads the program stored in the memory unit 253 into the RAM 252. The CPU 251 then runs the program to control and perform calculations in each part of the reference image generation device 111. The RAM 252 is a type of volatile memory that can be directly accessed by the CPU 251. The RAM 252 is also used as the CPU 251's work area or other temporary data storage area. The memory unit 253 functions as the temporary storage area and work memory of the reference image generation device 111. The image processing unit 258 generates a reference image. The image processing unit 258 also stores the reference image in the RAM 252.

[0022] Figure 3 is a schematic diagram showing the internal configuration of the image forming apparatus, inspection unit, and high-capacity stacker. As shown in Figure 3, the image forming apparatus 101 incorporates paper feed decks 103 and 104. In paper feed decks 103 and 104, only the top sheet of printing paper is separated and transported to the paper transport path 305. The image forming apparatus 101 also has developing stations 301 to 304, an intermediate transfer belt 306, and a fixing unit 308. Developing station 301 forms a toner image using yellow (Y) toner. Developing station 302 forms a toner image using magenta (M) toner. Developing station 303 forms a toner image using cyan (C) toner. Developing station 304 forms a toner image using black (K) toner. Each toner image is first transferred to the intermediate transfer belt 306. The intermediate transfer belt 306 rotates clockwise in Figure 3. Each toner image on the intermediate transfer belt 306 is transferred to the printing paper transported from the paper transport path 305 at the secondary transfer position 307.

[0023] The fuser unit 308 has a pressure roller and a heating roller, and as the printing paper passes between these rollers, the toner on the printing paper can be melted and pressed. This fixes the toner image to the printing paper. After passing through the fuser unit 308, the printing paper passes through the paper transport path 309 and is transported to the paper transport path 312. Depending on the printing paper, further toner image fixing may be required. In this case, the printing paper that has passed through the fuser unit 308 is transported to the second fuser unit 310. The second fuser unit 310 can perform additional melting and pressing. After that, the printing paper passes through the paper transport path 311 and is transported to the paper transport path 312. Furthermore, when printing on both sides of the printing paper, the printing paper that has passed through the fuser unit 308 is transported to the paper reversal path 313 and reversed. After that, the printing paper is transported to the double-sided transport path 314, where the toner image is transferred to the back side at the secondary transfer position 307.

[0024] The inspection unit 106 has CIS315 and CIS316 positioned opposite each other. CIS315 is a sensor that reads the image on the top surface of the printed paper. CIS316 is a sensor that reads the image on the bottom surface of the printed paper. When the printed paper transported on the paper transport path 317 reaches a predetermined position, the inspection unit 106 scans (reads) the printed paper using CIS315 and CIS316. This scanned image is transmitted to the inspection device 108 via the inspection device I / F215 and accessory I / F231. The inspection device 108 determines whether or not there are defects in the scanned image. This determination result is transmitted to the inspection unit 106 via the inspection device I / F275 and accessory I / F221. The CPU 223 transmits this determination result to the large-capacity stacker 107 via accessory I / F221 and accessory I / F231.

[0025] The high-capacity stacker 107 has a main tray 324 for stacking printing paper. Printing paper that has passed through the inspection unit 106 is transported through the paper transport path 319 into the high-capacity stacker 107. The printing paper is then transported through the paper transport path 322 and stacked on the main tray 324. The high-capacity stacker 107 also has a top tray 320 as an output tray. Printing paper (printed material) in which defects are detected by the inspection device 108 is discharged to the top tray 320. When printing paper is to be output to the top tray 320, it is transported from the paper transport path 319 to the top tray 321. The high-capacity stacker 107 has a reversing unit 323 for reversing the printing paper. The reversing unit 323 is used when stacking printing paper on the main tray 324. The reversal in the reversal unit 323 allows the orientation of the printing paper when it is loaded onto the main tray 324 to be the same as the orientation of the printing paper when it is loaded into the large-capacity stacker 107; in other words, they can be made to be the same orientation.

[0026] Figure 4 is a block diagram showing the functional configuration of the CPUs of the information processing device, image forming apparatus, reference image generation apparatus, and inspection apparatus. Figure 4(a) is a block diagram showing the functional configuration of the CPU of the information processing device. Figure 4(b) is a block diagram showing the functional configuration of the CPU of the image forming apparatus. Figure 4(c) is a block diagram showing the functional configuration of the CPU of the reference image generation apparatus. Figure 4(d) is a block diagram showing the functional configuration of the CPU of the inspection apparatus. Figure 5 is a diagram showing an example of information regarding image assignment. As shown in Figure 4(a), the CPU 241 of the information processing device 109 has a display control unit 401, an image processing control unit 402, and a data control unit 403. The display control unit 401 displays a user-operable screen on the UI panel 243. Also, when a print job is set on the screen displayed on the UI panel 243, the display control unit 401 saves (stores) the print setting information in the RAM 242. Also, when printing is executed, the display control unit 401 sends information to that effect to the data control unit 403.

[0027] The image processing control unit 402 controls image processing. When the image processing control unit 402 (RIP processing execution means) receives information indicating that printing should be performed, it performs RIP processing to convert print data or document data into bitmap image data based on the print setting information stored in RAM 242. The RIP processing generates an image with a resolution set to 600 dpi or 1200 dpi. The RIP processing is also performed in the first and second processes described later. The image processing control unit 402 assigns a unique image ID to the RIP image according to the printing order. For example, the RIP image printed on the first sheet of paper is assigned image ID "1", and the RIP image printed on the second sheet of paper is assigned image ID "2". The data control unit 403 controls the reception of print jobs from the client PC 110 and the transmission of print jobs to the image forming apparatus 101 and the reference image generation apparatus 111. The data control unit 403 may also control the transmission of print jobs to and from the inspection apparatus 108. The data control unit 403 receives print jobs from the client PC 110 via the NW_I / F 247 and stores them in RAM 242. The data control unit 403 also sends print page start notifications and RIP images to the reference image generation device 111 via NW_I / F 246 and video I / F 245. Furthermore, the data control unit 403 sends print job start notifications and print setting information to the image forming apparatus 101 via NW_I / F 246. The data control unit 403 also obtains inspection job IDs from the image forming apparatus 101 and stores them in RAM 242.

[0028] As shown in Figure 4(b), the CPU 201 of the image forming apparatus 101 includes a data control unit 411, an image processing control unit 412, a print control unit 413, and a paper feed control unit 414. The data control unit 411 controls the reception of print jobs and notifications from the information processing device 109, and controls the transmission of job information and reference image information to the inspection device 108. The data control unit 411 also controls the transmission of image transfer start notifications to the reference image generation device 111. When the data control unit 411 receives a print job start notification from the information processing device 109, it stores the print setting information and RIP image obtained via the NW_I / F 207 and video I / F 206 in the RAM 202. In inspection jobs, reference image information and image assignment information are transmitted to the inspection device 108 via the NW_I / F 207. When registering a reference image, reference image information is generated for each page based on the print setting information. The reference image information includes various information such as the inspection job ID and image ID. Reference image information is transmitted to the inspection device 108. The reference image information also includes information on whether the printed paper is the last page of the print job. The image assignment information includes single-sided information based on the print setting information, i.e., information on whether it is single-sided or double-sided printing. The image assignment information also includes the amount of rotation and shift determined by the print control unit 413 when printing is performed on the printed paper, as well as information on the printing side, i.e., whether printing is performed on the front or back side, the sheet number (page number), etc.

[0029] The image assignment information 500 shown in Figure 5 is generated for each printed page. The image assignment information 500 includes print information related to the printing conditions, specifically the first information 501, second information 502, third information 503, fourth information 504, fifth information 505, sixth information 506, and seventh information 507. The first information 501 is the image ID for identifying the image, which is "1" in the configuration shown in Figure 5. The second information 502 is the job ID for identifying the print job, which is "6543" in the configuration shown in Figure 5. The third information 503 is information regarding whether it is single-sided or double-sided printing, which is "double-sided" in the configuration shown in Figure 5. This information is determined based on the print setting information set in the display control unit 401. The fourth information 504 is the sheet number, i.e., the page number, of the sheet (printing paper) that has been instructed to be transported by the paper feed control unit 414, which is "5" in the configuration shown in Figure 5. The fifth piece of information 505 is information regarding whether printing is performed on the front or back side, and in the configuration shown in Figure 5, it is "front side". The sixth piece of information 506 is information regarding the amount of rotation determined based on the print setting information, and in the configuration shown in Figure 5, it is "90 degrees". For example, if the rotation amount is 90 degrees, the RIP image from the information processing device 109 is rotated 90 degrees clockwise on the transported paper and imposed, and printing is performed. The seventh piece of information 507 is information regarding the amount of shift determined based on the print setting information, and in the configuration shown in Figure 5, it is "x=5, y=-5". For example, if the shift amount is x=5, y=-5, the leading edge of the transported paper is used as the origin, and the RIP image from the information processing device 109 is imposed by moving it +5 pixels in the main scanning direction and -5 pixels in the sub-scanning direction, and printing is performed. In addition, the image assignment information 500 may include information such as whether the paper is the last page of the print job.

[0030] The image processing control unit 412 acquires print processing information and RIP images stored in RAM 202 and performs image processing to convert them into print data. "Image processing to convert into print data" means, for example, rasterizing the PDL data to convert it into multi-level bitmap data and performing screen processing, etc. This converts it into binary bitmap data. The binary bitmap data is transmitted to the printer engine 210 via engine I / F 209. The print control unit 413 controls the printer engine 210 via engine I / F 209. The print control unit 413 issues an instruction to print the bitmap data from the image processing control unit 412 onto the printing paper. The paper feed control unit 414 controls the paper feed deck 211 via paper feed deck I / F 204. Based on the print processing information stored in RAM 202, the paper feed control unit 414 transports paper from the paper feed deck 211 to the printer engine 210.

[0031] As shown in Figure 4(c), the CPU 251 of the reference image generation device 111 has a data control unit 421 and an image processing control unit 422. The data control unit 421 controls the reception of image transfer start notifications from the image forming apparatus 101 and controls the transmission of reference image data to the inspection device 108. The data control unit 421 receives image transfer start notifications from the image forming apparatus 101 via the NW_I / F 254 and stores them in the RAM 242. The data control unit 421 also receives RIP images from the information processing device 109 via the video I / F 255 and stores them in the RAM 242. The data control unit 421 also transmits reference image data to the inspection device 108 via the NW_I / F 254. The image processing control unit 422 controls the image processing unit 258. Based on the RIP image data and image transfer start information stored in the RAM 242, the image processing control unit 422 instructs the image processing unit 258 to generate a reference image with a resolution converted to 300 dpi.

[0032] As shown in Figure 4(d), the CPU 271 of the inspection device 108 includes a display control unit 431, a data control unit 432, and an inspection processing control unit 433. The display control unit 431 displays user-operable screens and inspection results of printed materials on the UI panel 2743. The display control unit 431 also saves inspection setting information to the RAM 272 when inspection operation settings are made on the screen displayed on the UI panel 274. The data control unit 432 receives reference image information and image assignment information from the image forming apparatus 101 via the NW_I / F 376 and saves it to the RAM 252. When the data control unit 432 receives a notification to start an inspection job, it generates an inspection job ID unique to the inspection job and saves the inspection job ID to the RAM 252. The data control unit 432 also saves the reference image obtained via the communication I / F 276 to the RAM 252. Furthermore, the data control unit 432 notifies the inspection unit 110 of the inspection results from the inspection processing control unit 433 and the inspection setting information stored in the RAM 252. The inspection processing control unit 433 controls the inspection processing unit 278.

[0033] Figure 6 is a flowchart of the process (communication decision process for the reference image generation device) executed by the image forming apparatus. The program based on the flowchart shown in Figure 6 is stored in the memory unit 205 of the image forming apparatus 101 and executed by the CPU 201. This program is also started when the image forming apparatus 101 is started up. As shown in Figure 6, in step S601, the CPU 201 of the image forming apparatus 101 determines whether or not the reference image generation device 111 is present in the inspection system 1000. If the determination in step S601 is made to show that the reference image generation device 111 is present, the process proceeds to step S602. On the other hand, if it is determined that the reference image generation device 111 is absent, the process ends.

[0034] In step S602, the CPU 201 notifies the reference image generation device 111 via the NW_I / F 207 of information regarding the model of the image forming apparatus 101. "Model of the image forming apparatus 101" refers to a value indicating the model of the image forming apparatus 101, which is stored in the storage unit 205. After step S602 is executed, the process ends. When the reference image generation device 111 receives information regarding the model of the image forming apparatus 101, it stores this information in the storage unit 253. The reference image generation device 111 then sets a value corresponding to the model of the image forming apparatus 101. After this setting, the CPU 251 of the reference image generation device 111 notifies the information processing device 109 via the video I / F 255 that it is ready to receive jobs.

[0035] Figure 7 shows a screen for specifying the inspection mode in the job properties of the information processing device. The job properties screen 701 shown in Figure 7 is stored in the storage unit 244 of the information processing device 109. This job properties screen 701 is displayed on the UI panel 243 by the display control unit 401 when the user operates the UI panel 243 to instruct the setting of the inspection mode. The job properties screen 701 includes areas 702 to 704 and a button 705. Area 702 is the area for specifying whether or not to perform inspection with the inspection device 108. If inspection is specified in area 702, that is, if inspection ON is selected, the data control unit 403 notifies the image forming apparatus 101 to start an inspection job with the settings in areas 703 and 704 added, and obtains the inspection job ID. After obtaining the inspection job ID, the inspection job ID is set in the print job and sent to the image forming apparatus 101. Area 703 is the area for selecting the area to be inspected and how to set its level. For example, if "Default" is selected, the inspection device 108 will inspect the entire surface of the image to be inspected at a standard level. If "Preset1" to "Preset10" are selected, the inspection device 108 will perform the inspection based on the pre-specified area and level. If "New Registration" is selected, it is possible to create a new inspection setting. The inspection device 108 will perform the inspection based on the new inspection setting. Area 704 is the area for specifying the inspection operation. The inspection operation is not particularly limited and can include, for example, performing only inspection setting registration, performing only inspection, or performing inspection with the specified inspection setting. Then, by pressing button 705 with the selection made in areas 702 to 704, the data control unit 403 sends a predetermined print job to the image forming apparatus 101.

[0036] Figure 8 is a flowchart showing the processing (job processing) performed in the image forming apparatus. The program based on the flowchart shown in Figure 8 is stored in the memory unit 205 of the image forming apparatus 101 and executed by the data control unit 411. This program is started when the data control unit 411 of the image forming apparatus 101 receives a print job. As shown in Figure 8, in step S801, the data control unit 411 determines whether the print job includes an inspection job. This determination is based on whether an inspection job ID is set for the print job. If an inspection job ID is set for the print job, it is determined that the print job is an inspection job, and the process proceeds to step S802. On the other hand, if an inspection job ID is not set for the print job, it is determined that the print job is not an inspection job, and the process proceeds to step S816.

[0037] In step S802, the data control unit 411 receives page information from the information processing device 109. The page information includes, for example, the number of pixels on the sheet, the image ID, the current number of copies, etc. The data control unit 411 stores this page information in the RAM 202.

[0038] In step S803, the data control unit 411 transmits reference image information to the inspection device 108.

[0039] In step S804, the data control unit 411 receives an image transfer start notification from the information processing device 109.

[0040] In step S805, the data control unit 411 reads the job inspection ID, image ID, pixel count, and image resolution of the job stored in the RAM 202. The data control unit 411 then transmits this read information to the reference image generation device 111 as a reference image generation preparation notification.

[0041] In step S806, the data control unit 411 receives a notification from the reference image generation device 111 that the reference image generation preparation is complete (see step S903).

[0042] In step S807, the data control unit 411 instructs the image processing control unit 412 to prepare for receiving image data.

[0043] In step S808, the data control unit 411 instructs the information processing unit 109 to start image transfer when the reference image generation device 111 is ready to receive the image and the image forming apparatus 101 is ready to receive the image. When the information processing unit 109 is instructed to start image transfer, it transmits the RIP image to the reference image generation device 111 via the video I / F 245. This RIP image is also transmitted to the image forming apparatus 101 by the branching function of the reference image generation device 111.

[0044] In step S809, the data control unit 411 receives an image transfer completion notification from the information processing device 109. An "image transfer completion notification" is a notification sent from the information processing device 109 when the transmission of the RIP image is completed.

[0045] In step S810, the data control unit 411 sends a reference image generation confirmation notification to the reference image generation device 111. The "reference image generation completion notification" is a notification to confirm whether or not the reference image generation process in the reference image generation device 111 has been completed.

[0046] In step S811, the data control unit 411 receives a notification from the reference image generation device 111 indicating that the reference image generation is complete (see step S906).

[0047] In step S812, the data control unit 411 determines whether the RIP image was successfully received via the video interface 206. If the determination in step S812 indicates that the RIP image was successfully received, the process proceeds to step S813. In this case, the RIP image is saved in RAM 202. On the other hand, if the determination in step S812 indicates that the RIP image was not successfully received, the process proceeds to step S815. In this case, because the image size is relatively large, the image will not be saved in RAM 202 even if it is compressed.

[0048] In step S813, the data control unit 411 notifies the information processing device 109 of the success of image transfer when the reference image generation in the reference image generation device 111 is successfully completed and the image reception in the image forming device 101 is successfully completed.

[0049] In step S814, the data control unit 411 determines whether the received image is the last page based on the sheet information stored in the RAM 202. If the determination in step S814 is that it is the last page, the process ends. On the other hand, if the determination in step S814 is that it is not the last page, the process returns to step S802 and the subsequent steps are executed in order.

[0050] In step S815, the data control unit 411 notifies the information processing device 109 of the image transfer failure. After step S815 is executed, the process returns to step S804 and the subsequent steps are executed in order.

[0051] In step S816, the data control unit 411 performs normal printing processing.

[0052] Figure 9A is a flowchart showing the processing performed by the reference image generation device (synchronization processing with the image forming apparatus). The program based on the flowchart shown in Figure 9A starts when the data control unit 421 of the reference image generation device 111 receives a reference image generation preparation notification (see step S805) from the image forming apparatus 101. As shown in Figure 9A, in step S901, the data control unit 421 of the reference image generation device 111 instructs the image processing control unit 422 to prepare for the generation of a reference image. The image processing control unit 422 prepares to receive the RIP image via the video I / F 255 in accordance with this instruction. When this preparation is complete, the image processing control unit 422 notifies the data control unit 421 that the reference image generation preparation is complete. The data control unit 421 also saves the information received in the reference image generation preparation notification to the RAM 252.

[0053] In step S902, the data control unit 421 receives a notification from the image processing control unit 422 that the reference image generation preparation is complete.

[0054] In step S903, the data control unit 421 notifies the image forming apparatus 101 that preparation for reference image generation is complete. This notification corresponds to step S806 in the flowchart shown in Figure 8. After sending the notification that preparation for reference image generation is complete, the RIP image is transmitted from the information processing device 109. When the RIP image is received, the image processing control unit 422 starts generating the reference image.

[0055] In step S904, the data control unit 421 determines whether or not it has received a reference image generation confirmation notification (see step S810) from the image forming apparatus 101. If the determination in step S904 determines that a reference image generation confirmation notification has been received, the process proceeds to step S905. On the other hand, if the determination in step S904 determines that a reference image generation confirmation notification has not been received, the process proceeds to step S907.

[0056] In step S905, the data control unit 421 receives a notification from the image processing control unit 422 that the reference image generation has finished.

[0057] In step S906, the data control unit 421 receives a reference image generation confirmation notification from the image forming apparatus 101, and if it confirms that the reference image generation is complete in the reference image generation device 111, it sends a reference image generation completion notification to the image forming apparatus 101. This notification corresponds to step S811 in the flowchart shown in Figure 8. After step S906 is executed, the process ends.

[0058] In step S907, the data control unit 421 receives a reference image generation completion notification from the image processing control unit 422. The process proceeds to step S907 only when the reference image generation preparation completion notification arrives earlier than the reference image generation confirmation notification.

[0059] In step S908, the data control unit 421 receives a reference image generation confirmation notification from the image forming apparatus 101 (see step S810). After step S908 is executed, the process proceeds to step S906.

[0060] Figure 9B is a flowchart showing the process performed by the reference image generation device (the process of transmitting a reference image to the inspection device). The program based on the flowchart shown in Figure 9B is started when the data control unit 421 receives a notification from the image processing control unit 422 that the reference image compression is complete. As shown in Figure 9B, in step S1901, the data control unit 421 of the reference image generation device 111 reads the reference image stored in the RAM 252 and the reference image information, which includes the inspection job ID and the image ID.

[0061] In step S1902, the data control unit 421 adds reference image information to the reference image read in step S1901. Then, the data control unit 421 transmits the reference image with the added reference image information to the inspection device 108. After step S1902 is executed, the process ends.

[0062] Figure 9C is a flowchart showing the processing (transmission of image allocation information) performed in the image forming apparatus. The program based on the flowchart shown in Figure 9C is started when the data control unit 411 of the image forming apparatus 101 receives a print job. As shown in Figure 9C, in step S2001, the data control unit 411 receives print setting information from the information processing device 109 and stores it in the RAM 202.

[0063] In step S2001, the data control unit 411 receives the RIP image from the information processing device 109 and stores it in the RAM 202.

[0064] In step S2003, the data control unit 411 determines whether the image assignment information has been finalized. This determination is based, for example, on whether all items of the image assignment information 500 shown in Figure 5 are present. If all items are present, it is determined that the image assignment information has been finalized, and the process proceeds to step S2004. On the other hand, if not all items are present, it is determined that the image assignment information has not been finalized, and the process returns to step S2001, and the subsequent steps are executed in order. One example of a situation where not all items are present is when the reverse-order printing function of the image forming apparatus 101 is executed. When the reverse-order printing function is executed, the transmitted RIP images are not printed in the correct order. Therefore, the sheet number cannot be determined until all pages of the print job's RIP images are received, resulting in a state where not all items of the image assignment information are present.

[0065] In step S2004, the data control unit 411 transmits image assignment information to the inspection device 108.

[0066] In step S2005, the data control unit 411 determines whether the image assignment information transmitted in step S2004 relates to the last page. If the determination in step S2005 is that it relates to the last page, the process proceeds to step S2006. On the other hand, if the determination in step S2005 is that it does not relate to the last page, the process returns to step S2001 and executes the subsequent steps in order.

[0067] In step S2006, the data control unit 411 determines whether or not it has sent the image assignment information for all pages of the print job to the inspection device 108. If the determination in step S2006 is that the image assignment information for all pages has been sent, the process ends. On the other hand, if the determination in step S2006 is that the image assignment information for all pages has not been sent, the process proceeds to step S2007.

[0068] In step S2007, the data control unit 411 transmits image assignment information to the inspection device 108.

[0069] Figure 10 is a flowchart of the process (inspection process) performed by the inspection device. The program based on the flowchart shown in Figure 10 starts when image assignment information (see step S2004 or step S2007) is received. As shown in Figure 10, in step S1001, the inspection process control unit 433 refers to the inspection job ID and image ID included in the image assignment information and reads the reference image associated with the said inspection job ID and image ID.

[0070] In step S1002, the inspection processing control unit 433 of the inspection device 108 processes the reference image read in step S1001 based on the image assignment information stored in the RAM 272. For example, in the case of image assignment information 500 (see Figure 5), this processing includes rotating the reference image by 90 degrees, moving it by +5 pixels in the main scanning direction and by -5 pixels in the sub-scanning direction, with the leading edge of the paper transport direction as the origin.

[0071] In step S1003, the inspection processing control unit 433 reads out the scanned image (see step S1124).

[0072] In step S1004, the inspection processing control unit 433 performs an inspection by comparing the reference image processed in step S1002 with the scanned image read out in step S1003. Specifically, it first extracts feature points from the reference image and the scanned image. Next, it aligns the reference image and the scanned image based on each feature point. Then, it determines whether the difference between the pixel value (luminance value) of the inspected pixel in the aligned scanned image and the pixel value (luminance value) of the comparison target pixel in the reference image is below a threshold. If the result of this determination is below the threshold, the inspected pixel is judged to be acceptable. Note that the threshold differs for each inspection level. This inspection is performed for each reference image corresponding to each scanned image. After the inspection of all pixels is completed, it determines whether the total number of pixels judged to be unacceptable is below the acceptance threshold. Based on the result of this determination, it is determined whether the scanned image is normal or not. For example, if the total number of pixels judged to be unacceptable is below the acceptance threshold, the scanned image can be judged to be normal. On the other hand, if the total number of pixels judged to be unacceptable exceeds the acceptance threshold, the scanned image can be judged to be abnormal. Furthermore, information such as whether or not the printed material has defects, the type of defect (e.g., dots or streaks), and the location of the defect are stored in RAM272. After step S1004 is executed, the process ends.

[0073] Figure 11 is a flowchart showing the processes performed between the information processing device, the image forming apparatus, the reference image generation device, the inspection unit, and the inspection device. As shown in Figure 11, in step S1101, the data control unit 403 (CPU 241) of the information processing device 109 transmits page information relating to the printed material to be inspected to the image forming apparatus 101. The page information includes, for example, the image ID and the number of pixels in the image. The data control unit 411 of the image forming apparatus 101 receives the page information from the information processing device 109. The page information is stored in the RAM 202 of the image forming apparatus 101.

[0074] In step S1102, the data control unit 411 (CPU 201) of the image forming apparatus 101 transmits reference image information regarding the printed material to be inspected to the inspection apparatus 108. The data control unit 432 (CPU 271) of the inspection apparatus 108 receives the reference image information from the image forming apparatus 101. The reference image information is stored in the RAM 272 of the inspection apparatus 108.

[0075] In step S1103, the data control unit 403 of the information processing device 109 sends an image transfer start notification to the image forming apparatus 101. The data control unit 411 of the image forming apparatus 101 receives the image transfer start notification from the information processing device 109.

[0076] In step S1104, the data control unit 411 of the image forming apparatus 101 sends a reference image generation preparation notification to the reference image generation device 111. The data control unit 421 of the reference image generation device 111 receives the reference image generation preparation notification from the image forming apparatus 101.

[0077] In step S1105, the data control unit 403 of the information processing device 109 transmits image data of the printed material to be inspected to the reference image generation device 111. This image data is the print data that will become the printed material when printed in step S1122. The data control unit 421 (CPU 251) of the reference image generation device 111 receives the image data from the information processing device 109. The image data is stored in the RAM 252 of the reference image generation device 111.

[0078] In step S1106, the data control unit 421 of the reference image generation device 111 transmits image data to the image forming apparatus 101 using its branching function. The data control unit 421 of the image forming apparatus 101 receives the image data from the reference image generation device 111.

[0079] In step S1107, the data control unit 403 of the information processing device 109 detects the completion of image data transmission in step S1105 and sends an image transfer completion notification to the image forming apparatus 101. The data control unit 411 of the image forming apparatus 101 receives the image transfer completion notification from the information processing device 109.

[0080] In step S1108, the data control unit 411 of the image forming apparatus 101 sends a reference image generation confirmation notification to the reference image generation device 111. The data control unit 421 of the reference image generation device 111 receives the reference image generation confirmation notification from the image forming apparatus 101.

[0081] In step S1111, the image processing unit 258 of the reference image generation device 111 generates a reference image to be used as the basis for the inspection. This reference image is generated by performing a predetermined process (e.g., RIP processing) on ​​the same image data that was transmitted to the image forming apparatus 101 in step S1106. The image processing unit 258 also compresses the reference image and stores it in RAM 252.

[0082] In step S1112, the image processing unit 258 of the reference image generation device 111 transmits the reference image stored in the RAM 252 in step S1111 to the inspection device 108.

[0083] In step S1113, the data control unit 432 of the inspection device 108 saves the reference image from the reference image generation device 111 to the RAM 272. At this time, the reference image is saved in association with the inspection job ID and the image ID. Hereinafter, steps S1111 to S1113 (the part enclosed in a rectangle (a) in Figure 11) will be referred to as the "first process" which processes the image data as the reference image.

[0084] In step S1121, the data control unit 411 of the image forming apparatus 101 transmits the image allocation information to the inspection apparatus 108 once the image allocation information has been finalized. The data control unit 432 of the inspection apparatus 108 stores the image allocation information from the image forming apparatus 101 in the RAM 272. Note that step S1121 may be executed as soon as the image allocation information is finalized, provided that step S1106 has been executed.

[0085] In step S1122, the print control unit 413 of the image forming apparatus 101 controls the printer engine 210 to print the image data received from the reference image generation device 111 in step S1106 onto the printing paper (sheet). This printing process outputs (acquires) a printed product, i.e., a printed sheet.

[0086] In step S1123, the CPU 223 of the inspection unit 106 controls the imaging unit 225 to photograph (scan) the printed document output in step S1122. As a result, the printed document is read and a scanned image (scanned image data) of the printed document is acquired.

[0087] In step S1124, the CPU 223 of the inspection unit 106 transmits the scan image acquired in step S1123 to the inspection device 108. The data control unit 432 of the inspection device 108 receives the scan image from the inspection unit 106. The scan image is stored in the RAM 272 of the inspection device 108.

[0088] In step S1125, the inspection processing unit 278 of the inspection device 108 compares the scan image stored in RAM 272 in step S1124 with the reference image stored in RAM 272 in step S1113. This allows the aforementioned inspection process (see Figure 10) to be executed. The result of the inspection process (inspection result) is stored in RAM 272.

[0089] In step S1126, the data control unit 432 of the inspection device 108 transmits the inspection results stored in the RAM 272 in step S1125 to the inspection unit 106. The CPU 223 of the inspection unit 106 receives the inspection results from the inspection device 108. The inspection results are stored in the RAM 224 of the inspection unit 106.

[0090] In step S1127, the CPU 223 of the inspection unit 106 transmits the inspection results stored in the RAM 224 to the image forming apparatus 101. The data control unit 411 of the image forming apparatus 101 receives the inspection results from the inspection unit 106. The inspection results are stored in the RAM 202. The data control unit 411 then performs processing according to the inspection results. For example, if the printed material is judged to be free of defects (hereinafter referred to as "inspection result GOOD"), the data control unit 411 ejects the printed material to the main tray 324. If the printed material is judged to have defects (hereinafter referred to as "inspection result NG"), the data control unit 411 ejects the printed material to the top tray 320. The data control unit 411 may also display the inspection results on the UI panel 203. This notifies the user of the inspection results (processing results in the second process), allowing the user to understand the inspection results. Hereinafter, steps S1121 to S1127 (the part enclosed in a rectangle labeled (b) in Figure 11) are referred to as the "second process," which involves comparing the scanned image with a reference image during inspection. As shown in Figure 11, the first and second processes are executed in parallel (process execution process). This eliminates the waiting time that would otherwise be required to wait for the print inspection to begin until the reference image is generated and saved. This elimination of waiting time allows the print inspection to begin quickly. Note that each part and means used in the process execution process can be referred to as the "process execution means."

[0091] Furthermore, if the printed material is a booklet with multiple pages, there will be the same number of image data as there are pages. In the first process, a reference image is generated for each page and stored in RAM272. In the second process, as each reference image is generated in the first process, an inspection is performed by comparing the scanned image of each page with the reference image. In particular, in the second process, it is preferable to compare the scanned image of the page corresponding to the reference image of that page with the reference image of that page each time a reference image for that page is generated in the first process. This allows the inspection to be performed more quickly.

[0092] <Second Embodiment> The second embodiment will be described below with reference to Figures 12 to 15, focusing on the differences from the previously described embodiment, and omitting explanations of similar matters. Figure 12 is a flowchart showing the processes executed by the inspection device according to the second embodiment. As shown in Figure 12, in step S1201, the inspection processing control unit 433 of the inspection device 108 refers to the inspection job ID and image ID included in the image assignment information and determines whether or not there is a reference image associated with the same inspection job ID and image ID. If the determination in step S1201 is made to determine that there is a reference image, the process proceeds to step S1202. On the other hand, if the determination in step S1201 is made to determine that there is no reference image, the process proceeds to step S1206.

[0093] Steps S1202 to S1205 are the same as steps 1001 to S1004 in the flowchart shown in Figure 10.

[0094] In step S1206, the inspection processing control unit 433 cancels the inspection process. The inspection processing control unit 433 also transmits information to the display control unit 431 indicating that the inspection process has been canceled. The display control unit 431 displays the inspection status screen 1301 as an image indicating that the execution of the second process has been canceled. The inspection processing control unit 433 also notifies the image forming apparatus 101 of the cancellation of the print job via the data control unit 432. After step S1206 is executed, the process ends.

[0095] Figure 13 shows the screen displayed on the UI panel of the inspection device. The inspection status screen 1301 shown in Figure 13 is stored in the memory unit 273. The inspection processing control unit 433 displays the inspection status screen 1301 on the UI panel 274 by controlling the display control unit 431. The inspection status screen 1301 includes an inspection button 1302, an inspection status 1303, an inspection result list 1304, and the first inspection information 1305 to the seventh inspection information 1311. The inspection button 1302 accepts the execution or stopping of an inspection by user operation. This makes it possible to forcibly execute or stop an inspection at any time. For example, by pressing the inspection button 1302, the string attached to the inspection button 1302 changes to "Stop Inspection", and the inspection status 1303 changes to "Inspecting". Then, when the display control unit 431 receives a notification to stop the inspection, the inspection status changes to "Error". The first inspection information 1305 is the number of sheets that have been inspected. The second inspection information, 1306, is the number of sheets that failed the inspection. The third inspection information, 1307, is the ratio of sheets that failed the inspection to the number of sheets that were inspected, i.e., the defect rate. The fourth inspection information, 1308, is the number of occurrences of misaligned print positions, which is one of the causes of a failed inspection. The fifth inspection information, 1309, is the number of occurrences of circular defects (dots), which is one of the causes of a failed inspection. The sixth inspection information, 1310, is the number of occurrences of linear defects (streaks), which is one of the causes of a failed inspection. The seventh inspection information, 1311, is the number of sheets that were judged to be equivalent to a failed inspection because the inspection did not finish within the specified inspection time and resulted in a timeout error.

[0096] The inspection result list 1304 includes items 1304a to 1304f. Items 1304a to 1304f are populated with predetermined information each time an inspection result of NG occurs. Item 1304a is the number of the printed paper (sheet) that resulted in an inspection result of NG. Item 1304b is information on whether the side of the printed paper that resulted in an inspection result of NG was the front side or the back side. Item 1304c is the cause of the inspection result of NG. Item 1304d is the inspection time. Item 1304e is a link operation to the NG details screen. By pressing "Details" in item 1304e, the inspection processing control unit 433 controls the display control unit 431 to display a screen on the UI panel 274 that allows viewing of the captured image, defect location, etc., that resulted in the inspection result of NG. The type of defect, etc., can be understood from this inspection result list 1304.

[0097] As described above, in the inspection system 1000, if it is determined that there is no reference image when image assignment information is received, that is, if the first process was not executed, the inspection is canceled, that is, the execution of the second process is canceled. This prevents unnecessary inspections. The determination of whether or not the first process was executed is made, for example, by the data control unit 421 (determination means) of the reference image generation device 111. In addition, if it is determined that there is no reference image, the display of the inspection status screen 1301 may be suppressed. Furthermore, for example, if a reference image is acquired but a scan image is not acquired, this may be added to the inspection result NG as an image missing.

[0098] Figure 14 shows the screen displayed on the UI panel of the inspection device. The setting screen 1401 shown in Figure 14 is a screen for specifying the operation when a reference image is not registered in the inspection device 108. The setting screen 1401 is stored in the storage unit 273. When set to environment setting mode, the inspection processing control unit 433 displays the setting screen 1401 on the UI panel 274 by controlling the display control unit 431. The setting screen 1401 includes the operation when a reference image is not registered 1402, time 1403, and OK button 1404. In the operation when a reference image is not registered 1402, the operation setting for when a reference image is not registered during inspection is accepted. If "Wait until a reference image is registered" is selected in the operation when a reference image is not registered 1402, the desired time can be entered in time 1403. As a result, the inspection processing control unit 433 temporarily stops the inspection process for the amount of time entered in time 1403. Furthermore, if "Do not wait for reference image registration" is selected in the "Operation when reference image is not registered" 1402, the inspection processing control unit 433 cancels the inspection process. Then, by pressing the OK button 1404 with the "Operation when reference image is not registered" 1402 set, the display control unit 431 controls the data control unit 432 to record the information (environment setting information) set in the "Operation when reference image is not registered" 1402 into the storage unit 273.

[0099] Figure 15 is a flowchart of the process (modified) performed by the inspection device. As shown in Figure 15, steps S1501 and S1505 to S1509 are the same as steps 1201 to S1205 in the flowchart shown in Figure 12. If the result of the determination in step S1501 is that there is no reference image, the process proceeds to step S1502. In step S1502, the inspection processing control unit 433 of the inspection device 108 refers to the environment setting information recorded in the storage unit 273 and determines whether "Wait until a reference image is registered" is set. If the result of the determination in step S1502 is that the setting is present, the process proceeds to step S1503. On the other hand, if the result of the determination in step S1502 is that the setting is not present, the process proceeds to step S1505.

[0100] In step S1503, the inspection processing control unit 433 reads the waiting time entered at time 1403 by referring to the environment setting information recorded in the storage unit 273. Then, the inspection processing control unit 433 temporarily stops the inspection process, that is, waits, for the duration of the waiting time. After the waiting time has elapsed, the process proceeds to step S1504.

[0101] In step S1504, similar to step S1501, the inspection processing control unit 433 refers to the inspection job ID and image ID included in the image assignment information and determines whether or not there is a reference image associated with the same inspection job ID and image ID. If the determination in step S1504 is made to determine that a reference image exists, the process proceeds to step S1506. On the other hand, if the determination in step S1504 is made to determine that there is no reference image, the process proceeds to step S1505.

[0102] In step S1505, the inspection processing control unit 433 transmits information to the image forming apparatus 101 indicating that the inspection process has been canceled.

[0103] As described above, in the inspection system 1000, if it is determined that there is no reference image, and then, after a predetermined time has elapsed since that determination, it is determined that there is a reference image, the inspection process (second process) can be executed. On the other hand, if it is still determined that there is no reference image even after the predetermined time has elapsed, the inspection process can be stopped. With this configuration, the inspection process can be executed as much as possible.

[0104] <Third Embodiment> The third embodiment will be described below with reference to Figures 16 and 17, focusing on the differences from the previously described embodiment, and omitting explanations of similar matters. Figure 16 is a flowchart showing the process performed by the inspection device according to the third embodiment. As shown in Figure 16, in step S1601, the inspection processing control unit 433 of the inspection device 108 refers to the inspection job ID and image ID included in the image assignment information and determines whether there is a reference image associated with the same inspection job ID and image ID. If the determination in step S1601 is made to determine that there is a reference image, the process ends. This prevents the unnecessary saving of reference images. On the other hand, if the determination in step S1601 is made to determine that there is no reference image, the process proceeds to step S1602.

[0105] In step S1602, the inspection processing control unit 433 saves the reference image to the RAM 272, and the processing ends.

[0106] Figure 17 is a flowchart of the process (modified) performed by the inspection device. As shown in Figure 17, steps S1701 and S1704 are the same as steps 1601 and S1602 in the flowchart shown in Figure 16. If the judgment in step S1601 determines that a reference image exists, the process proceeds to step S1702.

[0107] In step S1702, the inspection processing control unit 433 of the inspection device 108 saves a new reference image to the RAM 272.

[0108] In step S1703, the inspection processing control unit 433 deletes the reference image that was associated with the inspection job ID and image ID assigned to the reference image determined in step S1701, and that was stored in RAM 272 before step S1702 was executed. This allows the latest reference image to be used in the inspection process. After step S1703 is executed, the process ends. Steps S1702 and S1703 may be omitted, and the new reference image may be overwritten with the reference image already stored in RAM 272.

[0109] As described above, the inspection system 1000 can acquire image data multiple times. Each image data is used as a reference image, and if each reference image is the same as a reference image already stored in RAM 272, the storage of that reference image is omitted. On the other hand, if each reference image is different from a reference image already stored in RAM 272, the reference image from the most recent acquisition is stored in RAM 272, and the reference image already stored in RAM 272 is deleted from RAM 272. This configuration prevents the storage of unnecessary reference images and allows the use of the latest reference image in the inspection process.

[0110] <Fourth Embodiment> The fourth embodiment will now be described with reference to Figure 18, focusing on the differences from the previously described embodiments, and similar matters will be omitted from the explanation. Figure 18 is a flowchart of the processing (job processing) performed in the image forming apparatus according to the fourth embodiment. As shown in Figure 18, in step S1801, the data control unit 411 of the image forming apparatus 101 determines whether or not the print job includes an inspection job. If the determination in step S1801 is found to include an inspection job, the process proceeds to step S1802. On the other hand, if the determination in step S1801 is found not to include an inspection job, the process proceeds to step S1806.

[0111] In step S1802, the data control unit 411 starts the registration check, that is, the execution of processing adapted to the first and second processes (see Figure 11).

[0112] In step S1803, the data control unit 411 determines whether or not it has received an error notification from the print control unit 413 indicating that the image forming apparatus 101 is in an error state. An error state is a condition in which either the output of a printed document by the printer engine 210 or the acquisition of a scanned image by the imaging unit 225 is forcibly stopped. If the determination in step S1803 determines that an error notification has been received, the process proceeds to step S1804. On the other hand, if the determination in step S1803 determines that no error notification has been received, the process proceeds to step S1805.

[0113] In step S1804, the data control unit 411 controls the reference image generation device 111, the inspection unit 106, and the inspection device 108 to perform the registration process (first process). This allows the first process to be executed even if the image forming apparatus 101 is in an error state. After step S1804 is executed, the process returns to step S1803 and the subsequent steps are executed in order.

[0114] In step S1805, the data control unit 411 determines whether or not it has received a print job completion notification. If the determination in step S1805 indicates that a print job completion notification has been received, the process ends. On the other hand, if the determination in step S1805 indicates that a print job completion notification has not been received, the process returns to step S1802 and the subsequent steps are executed in order.

[0115] In step S1806, the data control unit 411 controls the printer engine 210 to perform normal printing without inspection. In this case, the assignment of inspection IDs and image IDs is omitted.

[0116] In step S1807, similar to step S1807, the data control unit 411 determines whether or not it has received a print job completion notification. If the determination in step S1807 indicates that a print job completion notification has been received, the process ends. On the other hand, if the determination in step S1807 indicates that a print job completion notification has not been received, the process returns to step S1806 and the subsequent steps are executed in order.

[0117] As described above, the inspection system 1000 can execute the first process even if the image forming apparatus 101 is in an error state. Furthermore, once the aforementioned forced stop is released and the error state of the image forming apparatus 101 is resolved, the parallel execution of the first and second processes can be resumed.

[0118] Although preferred embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications and changes are possible within the scope of its gist. The present invention can also be realized by supplying a program that implements one or more of the functions of the above embodiments to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. Furthermore, the present invention can also be realized by a circuit (e.g., an ASIC) that implements one or more functions.

[0119] Each embodiment of the disclosure includes the following configurations, methods, and programs. (Configuration 1) An inspection system for inspecting printed materials, A data acquisition means for acquiring print data that will become the printed material through printing, An inspection system characterized by comprising: a processing execution means that performs in parallel a first process of processing the printed data to be used as reference image data for the inspection; and a second process of performing an inspection by comparing scanned image data of the printed material, obtained by reading the printed material on which the printed data is printed, with the reference image data during the inspection. (Configuration 2) The inspection system according to Configuration 1, characterized in that it comprises a RIP processing execution means that performs RIP processing on the print data in the first and second processing. (Configuration 3) The printed material has multiple pages, In the first process, the reference image data for each page is generated as the reference image data. The inspection system according to configuration 1 or 2, characterized in that, in the second process, the scanned image data of each page is compared with the reference image data of each page in accordance with the generation of reference image data of each page in the first process. (Configuration 4) The inspection system according to Configuration 3, characterized in that, in the second process, each time a reference image data for one page is generated in the first process, the scanned image data of the page corresponding to the reference image data for one page is compared with the reference image data for one page for inspection. (Configuration 5) Equipped with a storage medium for storing data, The inspection system according to configuration 3 or 4, characterized in that, in the first process, reference image data for each page is stored in the storage medium. (Configuration 6) A printing means for printing the print data, The system comprises a reading means for reading the printed material on which the print data has been printed using the printing means, The inspection system according to any one of configurations 1 to 5, characterized in that the second process involves acquiring the printed material by the printing means and acquiring the scanned image data by the reading means. (Configuration 7) The inspection system according to Configuration 6, characterized in that the processing execution means can execute the first process even if one of the acquisition of the printed material by the printing means or the acquisition of the scanned image data by the reading means is forcibly stopped in the second process. (Configuration 8) The inspection system according to Configuration 7, characterized in that the processing execution means resumes the parallel execution of the first process and the second process when the forced stop is released. (Configuration 9) comprising a determination means for determining whether the first process has been executed, The inspection system according to any one of configurations 1 to 8, characterized in that the processing execution means cancels the execution of the second process if, as a result of the determination by the determination means, the first process is not executed. (Configuration 10) The inspection system according to Configuration 9, characterized in that the processing execution means executes the second process if, as a result of the determination by the determination means, it is determined that the first process has not been executed, and after a predetermined time has elapsed since that determination, it is determined that the first process has been executed, and if, even after the predetermined time has elapsed, it is determined that the first process has not been executed, it stops executing the second process. (Configuration 11) The inspection system according to Configuration 9 or 10, characterized in that it includes a notification means for notifying the system when the execution of the second process is discontinued. (Configuration 12) comprising a storage medium for storing the reference image data, The data acquisition means is capable of acquiring the print data multiple times. The inspection system according to any one of configurations 1 to 11, characterized in that the first process allows for processing each printout to be used as the reference image data, and if each reference image data is the same as the reference image data already stored in the storage medium, the storage of each reference image data in the storage medium is omitted. (Configuration 13) comprising a storage medium for storing the reference image data, The data acquisition means is capable of acquiring the print data multiple times. The inspection system according to any one of configurations 1 to 12, characterized in that the first process allows for processing each print data to be used as the reference image data, and if each reference image data differs from the reference image data already stored in the storage medium, the reference image data of the most recent print data among the reference image data is stored in the storage medium, and the reference image data already stored in the storage medium is deleted from the storage medium. (Configuration 14) The print data includes print information relating to the printing conditions, The inspection system according to any one of configurations 1 to 13, characterized in that the printed information is used during the inspection in the second process. (Configuration 15) An inspection system according to any one of Configurations 1 to 14, characterized by comprising a notification means for notifying the processing result in the second processing. (Method 1) A method for controlling an inspection system that performs inspection on printed materials, A data acquisition step to acquire print data that will become the printed material through printing, A control method for an inspection system, characterized by having a processing execution step which is performed in parallel: a first process which processes the printed data to be used as reference image data for the inspection; and a second process which, during the inspection, processes the scanned image data of the printed material obtained by reading the printed material on which the printed data is printed, and compares it with the reference image data for inspection. (Program 1) A program characterized by causing a computer to execute the control method described in Method 1. [Explanation of symbols]

[0120] 223 CPU 258 Image Processing Unit 278 Inspection Processing Unit 402 Image Processing Control Unit 411 Data Control Unit 414 Paper feed control unit 421 Data Control Unit 432 Data Control Unit 1000 inspection systems

Claims

1. An inspection system for inspecting printed materials, A data acquisition means for acquiring print data that will become the printed material through printing, An inspection system characterized by comprising: a processing execution means that performs in parallel a first process of processing the printed data to be used as reference image data for the inspection; and a second process of performing an inspection by comparing scanned image data of the printed material, obtained by reading the printed material on which the printed data is printed, with the reference image data.

2. The inspection system according to claim 1, further comprising RIP processing execution means for performing RIP processing on the print data in the first and second processing steps.

3. The aforementioned printed material has multiple pages, In the first process, the reference image data for each page is generated as the reference image data. The inspection system according to claim 1, characterized in that, in the second process, the scanned image data of each page is compared with the reference image data of each page in accordance with the generation of reference image data of each page in the first process.

4. The inspection system according to claim 3, characterized in that, in the second process, each time a reference image data for one page is generated in the first process, the scanned image data of the page corresponding to the reference image data for one page is compared with the reference image data for one page for inspection.

5. Equipped with a storage medium for storing data, The inspection system according to claim 3, characterized in that, in the first process, reference image data for each page is stored in the storage medium.

6. A printing means for printing the aforementioned print data, The system comprises a reading means for reading the printed material on which the print data has been printed using the printing means, The inspection system according to claim 1, characterized in that, in the second process, the printed material is acquired by the printing means and the scanned image data is acquired by the reading means.

7. The inspection system according to claim 6, characterized in that the processing execution means can execute the first process even if one of the acquisition of the printed material by the printing means or the acquisition of the scanned image data by the reading means is forcibly stopped in the second process.

8. The inspection system according to claim 7, characterized in that the processing execution means resumes the parallel execution of the first process and the second process when the forced stop is released.

9. The system includes a determination means for determining whether or not the first process has been performed, The inspection system according to claim 1, characterized in that the processing execution means cancels the execution of the second process if, as a result of the determination by the determination means, the first process is not executed.

10. The inspection system according to claim 9, characterized in that the processing execution means executes the second process if, as a result of the determination by the determination means, it is determined that the first process has not been executed, and after a predetermined time has elapsed since that determination, it is determined that the first process has been executed, and if, even after the predetermined time has elapsed, it is determined that the first process has not been executed, it is determined that the execution of the second process is stopped.

11. The inspection system according to claim 9, further characterized by comprising a notification means for notifying the system when the execution of the second process is discontinued.

12. The storage medium includes a storage medium for storing the aforementioned reference image data, The data acquisition means is capable of acquiring the print data multiple times. The inspection system according to claim 1, characterized in that the first process allows for processing each printout to be used as the reference image data, and if each reference image data is the same as the reference image data already stored in the storage medium, the storage of each reference image data in the storage medium is omitted.

13. The storage medium includes a storage medium for storing the aforementioned reference image data, The data acquisition means is capable of acquiring the print data multiple times. The inspection system according to claim 1, wherein the first process allows for processing each printout to be used as the reference image data, and if each reference image data differs from the reference image data already stored in the storage medium, the reference image data of the most recent printout among the reference image data is stored in the storage medium, and the reference image data already stored in the storage medium is deleted from the storage medium.

14. The aforementioned print data includes print information relating to the printing conditions. The inspection system according to claim 1, characterized in that the printed information is used in the inspection during the second process.

15. The inspection system according to claim 1, further comprising a notification means for notifying the processing result in the second process.

16. A method for controlling an inspection system that performs inspections on printed materials, A data acquisition step to acquire print data that will become the printed material through printing, A control method for an inspection system, characterized by having a processing execution step which is performed in parallel: a first process which processes the printed data to be used as reference image data for the inspection; and a second process which, during the inspection, compares scanned image data of the printed material obtained by reading the printed material on which the printed data is printed with the reference image data for inspection.

17. A program characterized by causing a computer to execute the control method described in claim 16.

Images