JP2020094891A - Image inspection device and image inspection method - Google Patents

Abstract

To enable appropriate defect detection according to a utilization form different from usual when the presence or absence of defect of printed matter is inspected.SOLUTION: Use environment information is acquired, which is information related to environment where printed matter is used. Then, based on the acquired use environment information, after setting a defect detection level and a defect detection type, an image obtained by scanning the printed matter and a correct answer image prepared in advance are compared with each other so as to perform inspection for determining the presence or absence of the defect of the printed matter and also perform only inspection on a level and kind required in the use environment, thereby the inspection with higher level than necessary is not performed.SELECTED DRAWING: Figure 3

Description

The present invention relates to an image inspection device and an image inspection method, and more particularly to a technique for inspecting an image formed on a sheet by an image forming device.

Conventionally, an image formed on a sheet by an image forming apparatus such as a printer is inspected by an image inspection apparatus to determine whether it is a good product or a defective product. For example, when an image formed on a sheet has stains or deviations in the formation position, these are detected by an image inspection device and discharged to a tray different from a non-defective item.

When a defective product is detected by the image inspection apparatus, it is important to set the defect detection level to determine how many defects are determined to be defective products. That is, usually, the image inspection apparatus has a defective product when the printed paper has a stain to the extent that the print image has stains or a displacement that can be recognized as a positional shift when directly inspecting the printed paper. The defect detection level is set so as to determine that Alternatively, the defect detection level can be increased, and if there is minute dirt or slight positional deviation, it can be determined as a defective product.

Patent Document 1 describes a technique in which an image inspection apparatus indicates a detected defect to a user, selects a defect/non-defect, and sets only a defect selected as a defect at the time of inspection.

JP, 2014-199244, A

By the way, there are various kinds of usage forms and usage environments of the paper on which the image is formed by the image forming apparatus. For example, a large size in which a plurality of B0 size (1030 mm×1456 mm) printed sheets are connected together There is a usage form in which the poster of is displayed outdoors such as on the wall of a building.

In the case where the printed matter such as such a large poster is displayed outdoors, the user who views the poster usually sees it from a place several meters or more away.
FIG. 1 shows an example (FIG. 1(B)) in which a document on which an image is formed (FIG. 1(A)) and a sheet on which an image is formed by the document are posted on the outer wall of a building.
When a manuscript x as shown in FIG. 1A is image-formed on a sheet as a large poster and a printed matter of the manuscript x is posted on a building y as shown in FIG. 1B, the user can copy the manuscript x. At least a few meters away.

In the case of a printed matter viewed at a distance of several meters or more as described above, a fine state on the original document x such as when the original document x is viewed up close is not known, and an image with a reduced resolution as shown in FIG. It is recognized by the user as x'.
Therefore, even if there is a relatively small stain on the printed image, the user who sees the printed matter does not notice the stain at all.
Therefore, when the image inspection apparatus performs defect detection at a defect detection level assuming a general usage pattern, even if there is relatively small dirt that cannot be discriminated by the user in the actual usage pattern, the image inspection apparatus determines that the product is defective. Resulting in. In this case, the printed matter judged to be defective is discarded and wasteful reprinting is performed to obtain a good product. However, in the conventional image inspection apparatus, the usage different from such a general usage pattern is used. No image inspection was performed assuming the morphology.

Further, in the case of the posted form as shown in FIG. 1B, the distance between the user and the printed product may change greatly depending on the position in the printed product posted. That is, at the lower end and the upper end of the image of the document x shown in FIG. 1B, the distance from the user who is viewing the image changes greatly.

In such a case, at the lower end of the image, a relatively small amount of dirt may be visible to the user because the distance from the user is small, while at the upper end of the image, the distance from the user becomes large. The user cannot detect the dirt unless it has a certain size of dirt. Therefore, in the case of a printed matter in such a usage form, the level at which a defect can be recognized changes depending on the position where an image is formed on the paper, but the conventional image inspection apparatus can handle such a change due to the position. It was difficult to detect such defects.

It is an object of the present invention to provide an image inspection device and an image inspection method capable of appropriately detecting defects that are suited to an unusual usage pattern.

The image inspection apparatus of the present invention, based on the use environment information obtained by the information acquisition unit and the use environment information that is information about the environment in which the printed matter is used, the defect detection level and the defect detection type. An inspection unit configured to perform an inspection for determining whether or not there is a defect in the printed matter by comparing an image obtained by scanning the printed matter with a correct image prepared in advance after being set.

In addition, the image inspection method of the present invention detects a defect based on use environment information acquisition processing for acquiring use environment information that is information related to the environment in which the printed matter is used, and use environment information acquired by the use environment information acquisition processing. After the level and the defect detection type are set, an inspection process is performed in which an image obtained by scanning a printed matter is compared with a correct answer image prepared in advance to perform an inspection for determining whether the printed matter has a defect.

According to the present invention, it is possible to perform an appropriate inspection suitable for the actual usage environment of the printed matter. Therefore, it is possible to determine the defect detection level that does not detect defects that are not noticeable to the person viewing the printed matter without having to recreate the usage environment and check the appearance, thus reducing the time to start printing. can do.

It is a figure for demonstrating an example of the usage environment which the embodiment of this invention assumes. It is a block diagram which shows the structural example of the whole system by the 1st Embodiment of this invention. It is a flow chart which shows inspection processing by the 1st example of an embodiment of the present invention. It is a flow chart which shows acquisition processing of use environment information by the 1st example of an embodiment of the present invention. It is a figure which shows the example of the usage information input screen by the 1st Embodiment of this invention. 5 is a flowchart showing a defect detection level determination process according to the first embodiment of the present invention. It is a figure which shows the example of the level table by the 1st Embodiment of this invention. 7 is a flowchart showing a defect detection type determination process according to the first embodiment of the present invention. It is a block diagram which shows the structural example of the whole system by the 2nd Embodiment of this invention. It is a flow chart which shows inspection processing by the 2nd example of an embodiment of the present invention. It is a figure which shows the example of the illuminance information input screen by the 2nd Embodiment of this invention. It is a figure which shows the example of the color temperature information input screen by the 2nd Embodiment of this invention. It is a figure which shows the example of the angle information input screen by the 2nd Embodiment of this invention. It is a flowchart which shows the simulation image process by the 2nd Embodiment of this invention. It is a flowchart which shows the simulation process of the distance by the 2nd Embodiment of this invention. It is a figure which shows the example of the reduction rate table by the 2nd Embodiment of this invention. It is a flowchart which shows the simulation process of the illuminance by the 2nd Embodiment of this invention. It is a figure which shows the example of the brightness|luminance change rate table by the 2nd Embodiment of this invention. It is a figure which shows the example of the image at the time of changing the brightness|luminance by the 2nd Embodiment of this invention. It is a flowchart which shows the color temperature simulation process by the 2nd Embodiment of this invention. It is a figure which shows the example of the color temperature change rate table by the 2nd Embodiment of this invention. It is a figure which shows the example of the image when changing the color temperature by the 2nd Embodiment of this invention. It is a flowchart which shows the simulation process of the angle by the 2nd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in order with reference to the drawings. In each of the embodiments described below, common parts are denoted by the same reference numerals, and redundant description will be omitted.
First, an example of usage of a printed matter to be inspected by the inspection device used in each embodiment of the present invention will be described.
In each of the embodiments of the present invention, as described in the section of [Problems to be Solved by the Invention], as an example, it is assumed that a relatively large printed matter is created by an image forming apparatus. That is, it is assumed that the original x as shown in FIG. 1A is image-formed on a sheet as a large poster and the printed matter of the original x is posted on the building y as shown in FIG. 1B. In such a case, the user who views the manuscript x′ posted in the building y looks at a distance of at least several meters from the manuscript x′. Note that as the paper used as the printed matter, various printing media such as various films other than paper can be applied, and the printed matter described in the present embodiment may be printed on a medium other than paper. included.

<1. First embodiment example>
A first embodiment example of the present invention will be described with reference to FIGS.
[1-1. System configuration]
FIG. 2 shows a system configuration example including the image inspection device 10 according to the present embodiment.
The image inspection apparatus 10 of the present embodiment scans an image formed on a sheet by an image forming apparatus (not shown) and inspects the image. In this case, the image inspection apparatus 10 may be built in the image forming apparatus.

The image inspection apparatus 10 is communicably connected to the print information management server 20 via the network 30. The print information management server 20 controls the image forming process (printing process) in the image forming apparatus and the inspection in the image inspection apparatus 10.

First, the configuration of the image inspection device 10 will be described.
The image inspection device 10 includes a control unit 11, a storage unit 12, a display unit 13, an inspection unit 14, and a communication unit 15.
The control unit 11 controls the inspection of the printed matter performed by the image inspection device 10.
The storage unit 12 stores an image to be inspected (scan image) and a correct answer image. The correct image is stored in the storage unit 12 by an initial operation when performing the inspection. In addition, information necessary for inspection such as usage environment information is also stored in the storage unit 12.

On the display unit 13, usage environment information and the like are displayed by an operator who performs the inspection work. In addition, the display unit 13 is configured as a touch panel, and when an input screen of the usage environment information or the like is displayed, the operator can receive a detailed input of the usage environment information by a touch operation. The display unit 13 functions as an information acquisition unit that performs use environment information acquisition processing for acquiring use environment information by receiving input of use environment information.

The inspection unit 14 inspects the printed matter conveyed from the image forming apparatus under the control of the control unit 11.
When the inspection unit 14 performs the inspection, the inspection unit 14 scans the printed matter with the scanner and acquires a scan image. The scan image acquired by the inspection unit 14 is stored in the storage unit 12.
Then, the inspection unit 14 reads the scan image and the correct answer image prepared in advance from the storage unit 12, compares the two images, and performs an inspection process of detecting a defect in the scan image. In this inspection process, the printed matter in which a defect is detected is determined to be a defective product.
Further, the inspection unit 14 discharges the printed matter determined to be a non-defective product and the printed matter determined to be a defective product to different trays.

The communication unit 15 communicates with the print information management server 20 via the network 30. In the present embodiment, the communication unit 15 functions as an information acquisition unit that performs information acquisition processing for acquiring usage environment information and the like in communication with the print information management server 20.

Next, the configuration of the print information management server 20 will be described.
The print information management server 20 includes an operation system (hereinafter referred to as “OS”) 21, a central control unit (hereinafter referred to as “CPU”) 22, a storage unit 23, print information management software 24, and a communication unit 25.

The OS 21 is software that centrally controls the operation of the print information management server 20.
The CPU 22 executes necessary software such as the print information management software 24 under the environment in which the OS 21 is activated to perform print information management processing and the like.
The storage unit 23 stores information necessary for the CPU 22 to execute the print information management software 24 and the like. Information about printed matter, usage environment information, and the like are also stored in the storage unit 23.

The print information management software 24 is software that manages print information when an image is formed (printed) by the image forming apparatus. In the case of this embodiment, the print information management software 24 also manages the usage environment of the printed matter on which the image is formed. A specific example of the usage environment will be described later.
The communication unit 25 communicates with the image inspection device 10 via the network 30. The communication unit 25 also communicates with an image forming apparatus (not shown).

[1-2. Overall flow of inspection processing]
FIG. 3 is a flowchart showing the overall flow when the image inspection device 10 inspects the printed matter in the present embodiment.
First, the control unit 11 of the image inspection apparatus 10 acquires usage environment information of the printed matter to be inspected (step S10). Details of the process of acquiring the usage environment information will be described later.

Next, the control unit 11 of the image inspection apparatus 10 determines the level of defect detection when inspecting a printed matter by using the acquired use environment information (step S20). Further, the control unit 11 uses the acquired use environment information to determine the type of defect detection when inspecting the printed matter (step S30). Details of these defect detection levels and types of defect detection will be described later.

Then, the inspection unit 14 of the image inspection apparatus 10 applies the determined defect detection level and the determined defect detection type, scans the conveyed printed matter, executes the inspection, and determines whether the printed matter has a defect. An inspection process for making a determination is performed (step S40). In this inspection process, a defect detection process for comparing a correct image prepared in advance with a scan image is performed. When the inspection unit 14 detects a defect, the inspection unit 14 discharges the defective printed matter (defective product) to a tray different from the non-defective printed matter.

[1-3. Use environment information acquisition processing]
FIG. 4 is a flowchart showing a process in which the control unit 11 of the image inspection device 10 acquires the usage environment information in step S10 (FIG. 3).
First, when the image inspection device 10 starts the process of acquiring the usage environment information, the control unit 11 determines whether the usage environment information is stored in the storage unit 12 (step S11). When it is determined in step S11 that the use environment information is stored in the storage unit 12 (Yes in step S11), the control unit 11 reads the use environment information stored in the storage unit 12 (step S12). ..

When it is determined in step S11 that the use environment information is not stored in the storage unit 12 (No in step S11), the control unit 11 communicates with the print information management server 20 to print the print information management server. It is determined whether or not the usage environment information is stored in the storage unit 23 of 20 (step S13).
When it is determined in step S13 that the use environment information is stored in the print information management server 20 side (Yes in step S13), the control unit 11 stores the print information management server 20 via the network 30. The use environment information stored in the unit 23 is received (step S14).

Further, when it is determined in step S13 that the usage environment information is not stored in the print information management server 20 side (No in step S13), the control unit 11 allows the operator to input the usage environment information. As described above, the usage information input screen is displayed on the display unit 13 (step S15).

Then, when any of the use environment information read in step S12, the use environment information received in step S14, and the use environment information input in step S15 can be acquired, the control unit 11 determines whether the use environment information The acquisition process ends.

FIG. 5 shows an example of the use environment information input screen 100 that prompts the operator to input the use environment information in step S15. The use environment information input screen 100 is a screen displayed on the display unit 13.
As shown in FIG. 5, on the use environment information input screen 100, a message “Please input distance information.” is displayed, and a distance input location 110 and a distance selection location 120 are displayed.

The distance input part 110 is provided with an input window 111 through which a worker can directly input the distance by numbers. In the display example of FIG. 5, the operator has input 35 (m) to the input window 111.
Further, the distance selection location 120 is provided with four steps of distance selection buttons 121 to 124. In the display example of FIG. 5, the distance selection button 121 is less than 2 m, the distance selection button 122 is 2 m or more and less than 10 m, the distance selection button 123 is 10 m or more and less than 50 m, and the distance selection button 124 is 50 m or more.

Using this distance selection location 120, the operator directly inputs the distance in the input window 111 or performs an input operation of selecting any one of the distance selection buttons 121 to 124.
The distance input here corresponds to the distance between the user who views the printed matter x′ and the printed matter x′ when the printed matter x′ is posted as shown in FIG. 1(B). This distance is assumed to be the shortest distance or the average distance.

[1-4. Defect detection level determination processing]
FIG. 6 is a flowchart showing a process in which the control unit 11 of the image inspection apparatus 10 determines the defect detection level in step S20 (FIG. 3).
First, the control unit 11 obtains the distance information obtained by the use environment information acquisition process (the process of the flowchart of FIG. 4) described above (step S21).
Then, the control unit 11 obtains the defect detection level associated with the value of the distance information obtained in step S21 from the level table prepared in advance (step S22). The control unit 11 executes the defect detection process in the inspection unit 14 by applying the defect detection level obtained from this level table.

FIG. 7 shows an example of the level table.
The level table shown in FIG. 7 shows four levels. This level table shows the correspondence between distance information and detection levels. That is, when the distance information is less than 2 m, the most severe defect detection level, level 4, is set. Further, when the distance information is 2 m or more and less than 10 m, level 3 which is a defect detection level one level looser than level 4 is set. Further, when the distance information is 10 m or more and less than 50 m, level 2 which is a defect detection level one level looser than level 3 is set. Further, when the distance information is 50 m or more, level 1 which is the loosest defect detection level is set.
For example, when the acquired distance information is 30 m, it corresponds to the column of “10 m or more and less than 50 m” of the level table, and the level 2 corresponding to that column is set.

By setting the defect detection level, the inspection unit 14 changes the standard for determining the size of a defect such as stain in an image as a defect when performing the defect detection process. That is, at the defect detection level of level 4, the inspection unit 14 determines that there is a defect even if there is a very small size stain. On the other hand, at the defect detection level of level 1, the inspection unit 14 determines that there is no defect even if there is a certain amount of dirt.

[1-5. Defect detection type determination processing]
FIG. 8 is a flowchart showing a process in which the control unit 11 of the image inspection apparatus 10 determines the defect detection type in step S30 (FIG. 3).
First, the control unit 11 acquires distance information from use environment information in the use environment information acquisition process (process of the flowchart of FIG. 4) described above (step S31).
Then, the control unit 11 determines whether or not the value of the distance information obtained in step S31 is larger than a preset threshold for defect detection type setting (step S32). Here, the threshold is set to 10 m, for example.

When it is determined in step S32 that the value of the set distance information is larger than the threshold for defect detection type setting (Yes in step S32), the inspection unit 14 selects one of a plurality of items for which defect detection processing is performed. In this, for example, the detection of a color shift defect is excluded from the inspection items (step S32). Inspection items (dirt, inclination, etc.) other than color shift are not excluded from the inspection items.
Further, when it is determined in step S32 that the value of the set distance information is equal to or less than the threshold for defect detection type setting (No in step S32), the inspection unit 14 performs a plurality of defect detection processes. Perform the inspection in the item.

As described above, according to the image inspection apparatus 10 of the present embodiment, the defect detection level when performing the defect detection process changes according to the distance the user views the printed matter, and the printed matter is actually posted. It is possible to detect defects suitable for Therefore, even if there is a defect that is judged to be defective in the normal defect detection process, if the defect is not noticeable in the actual usage pattern of the printed matter, it is judged as no defect, and the corresponding printed matter is determined. Is not discarded but is effectively used. In addition, the labor for reprinting is saved, and the time required to print the required number of copies can be shortened.

Further, as described with reference to the flowchart of FIG. 8, when the user views the printed matter relatively long, the color misregistration is excluded from the inspection items, so that the time and labor required for the color misregistration inspection are saved. It is possible to reduce the burden required for the inspection.
It should be noted that, in the example of FIG. 8, the type in which the inspection is omitted according to the distance is the color shift is an example, and other inspection items may be omitted according to the distance.

<2. Second embodiment example>
Next, a second embodiment of the present invention will be described with reference to FIGS. 9 to 23, the same parts as those of FIGS. 2 to 8 described in the first embodiment above are designated by the same reference numerals, and the duplicated description will be omitted.

[2-1. System configuration]
FIG. 9 shows a system configuration example including the image inspection apparatus 10 according to the present embodiment.
The image inspection apparatus 10 according to the present embodiment includes an image processing unit 16 in addition to the configuration of the image inspection apparatus 10 described in FIG. 1 according to the first embodiment.

The image processing unit 16 performs image processing on each of the scan image for performing the inspection and the correct answer image stored in the storage unit 12 under the control of the control unit 11. A specific example of performing image processing will be described later.
The other configurations of the image inspection apparatus 10 and the print information management server 20 are the same as those of the image inspection apparatus 10 and the print information management server 20 described in FIG. 1 of the first embodiment.

[2-2. Overall flow of inspection processing]
FIG. 10 is a flowchart showing the overall flow when the image inspection device 10 inspects a printed matter in the present embodiment.
First, the control unit 11 of the image inspection apparatus 10 acquires usage environment information of the printed matter to be inspected (step S10). As the process of acquiring the usage environment information, for example, the process described in the flowchart of FIG. 4 is applied.

Next, the image processing unit 16 of the image inspection apparatus 10 uses the acquired use environment information to perform image processing that imitates the appearance in the use environment for each of the scan image obtained by scanning the printed matter and the correct answer image. (Step S50).
After that, the control unit 11 of the image inspection apparatus 10 determines the type of defect detection when inspecting the printed matter, using the acquired use environment information (step S30). As the processing for determining the type of defect detection, for example, the processing described in the flowchart of FIG. 8 is applied.

Then, the inspection unit 14 of the image inspection apparatus 10 compares the scan image subjected to the image processing in step S50 with the correct image, and performs a process of detecting a defect in the scan image (step S60). At this time, the types of defect detection are compared with the types determined in step S30.
When the inspection unit 14 detects a defect, the inspection unit 14 discharges the defective printed matter (defective product) to a tray different from the non-defective printed matter.

[2-3. Setting up the operating environment]
In the case of the present embodiment, the image inspection device 10 uses three distances shown in FIGS. 11 to 13 as the use environment in addition to the distance information described in FIG. 5 of the first embodiment. Acquire information on (illuminance, color temperature, inclination angle).
FIG. 11 shows an example of the use environment information input screen for prompting the operator to input the use environment information in the present embodiment. The usage environment of this example is the illuminance of the place where the printed matter is displayed, and as shown in FIG. 11, the illuminance information input screen 200 is displayed on the display unit 13.
On the illuminance information input screen 200, a message “Please input illuminance information.” is displayed, and an illuminance input location 210 and an illuminance selection location 220 are displayed.

The illuminance input portion 210 is provided with an input window 211 through which the operator can directly input the value of illuminance. In the display example of FIG. 11, a state in which 800 (lux) is input to the input window 211 is shown.
Further, the illuminance selection location 220 is provided with four-stage illuminance selection buttons 221 to 224. In the display example of FIG. 11, the illuminance selection button 221 is a dark room (about 100 lux), the illuminance selection button 222 is a slightly dark room (about 300 lux), the illuminance selection button 223 is indoor (about 700 lux), and the illuminance selection button. Reference numeral 224 indicates the illuminance outdoors (1000 lux or more).

Using this illuminance input location 210, the operator inputs the value of the illuminance directly into the input window 211, or performs an input operation of selecting any one of the illuminance selection buttons 221 to 224.
The illuminance input here is the illuminance (brightness) of the place where the printed matter is displayed.

FIG. 12 shows another example of the use environment information input screen for prompting the operator to input the use environment information in the present embodiment. Here, the use environment is the color temperature of the place where the printed matter is displayed, and as shown in FIG. 12, a color temperature information input screen 300 is displayed on the display unit 13.
On the color temperature information input screen 300, a message “Please input color temperature information.” is displayed, and a color temperature input point 310 and a color temperature selection point 320 are displayed.

The color temperature input portion 310 is provided with an input window 311 through which a worker can directly input the value of the color temperature numerically. In the display example of FIG. 12, a state in which 4000 (K) is input to the input window 311 is shown.
Further, the color temperature selection location 320 is provided with four-stage color temperature selection buttons 321 to 324. In the display example of FIG. 12, the color temperature selection button 321 is a light bulb color (about 2500 K), the color temperature selection button 322 is warm white (about 3500 K), the color temperature selection button 323 is day white (about 5000 K), and the color temperature selection is The button 324 indicates a daylight color (about 6500K).

Using this color temperature input point 310, the operator directly inputs a color temperature value into the input window 311, or performs an input operation of selecting any one of the color temperature selection buttons 321 to 324.
The color temperature input here is the color temperature of the place where the printed matter is displayed.

FIG. 13 shows still another example of the use environment information input screen for prompting the operator to input the use environment information in the present embodiment. The use environment in this example is the inclination angle viewed from the user at the place where the printed matter is displayed, and as shown in FIG. 13, the angle information input screen 400 is displayed on the display unit 13.
On this angle information input screen 400, a message "Please input angle information." is displayed, and an angle input portion 410 is displayed.

The angle input portion 410 is provided with an input window 411 through which a worker can directly input the value of the tilt angle by numbers. The display example of FIG. 13 shows a state in which 30 (degrees) is input to the input window 411.
The angle input here is the inclination angle of the place where the printed matter is displayed.

In addition, in FIGS. 11 to 13, an example in which the operator inputs three pieces of information on the illuminance, the color temperature, and the inclination angle is shown. However, three pieces of information on the illuminance, the color temperature, and the inclination angle are input by the operator. It may be acquired from the storage unit 12 in the image inspection apparatus 10 or the print information management server 20.
Further, here, four types of use environments of distance, illuminance, color temperature, and inclination angle are all set as an example, but input of any use environment may be omitted as necessary.

[2-4. Simulated image processing]
FIG. 14 is a flowchart showing a process in which the image processing unit 16 of the image inspection apparatus 10 shown in FIG. 9 performs image processing on the scan image and the correct answer image based on the usage environment information. This flowchart shows details of the processing in step S50 of FIG.
First, the image processing unit 16 performs image processing simulating the distance on the scan image and the correct image (step S51). The image processing that simulates this distance is image processing that lowers the resolution of the image as the distance the user views the printed matter increases.

Next, the image processing unit 16 performs image processing that simulates illuminance on the scan image and the correct image (step S52). In the image processing for simulating the illuminance, for example, the conversion processing of the brightness of the image is performed assuming the appearance at the illuminance input on the illuminance information input screen 200 shown in FIG.

Next, the image processing unit 16 performs image processing that simulates color temperature on the scan image and the correct answer image (step S53). The image processing for simulating the color temperature is, for example, an image processing for converting the color of the image assuming the appearance at the color temperature input on the color temperature information input screen 300 shown in FIG.

Further, the image processing unit 16 performs image processing that simulates the angle on the scan image and the correct image (step S54). The image processing for simulating this angle is, for example, image processing for reducing an image into a trapezoid, which is assumed to look at the angle input on the angle information input screen 400 shown in FIG. Then, the inspection unit 14 of the image inspection device 10 performs an inspection process of comparing the scan image subjected to the image processing of steps S51 to S54 with the correct image.

FIG. 15 is a flowchart showing details of the image processing for simulating the distance in step S51 (FIG. 14).
First, the image processing unit 16 determines whether or not the acquired use environment information includes distance information (step S511). When it is determined in step S511 that the use environment information includes distance information (Yes in step S511), the image processing unit 16 prepares in advance a reduction rate associated with the value of the distance information. The reduction ratio table is acquired (step S512).
Then, the scan image and the correct answer image are reduced at the reduction ratio acquired in step S512 (step S513). By performing this reduction processing, the distance simulation processing is completed. If it is determined in step S511 that the use environment information does not include distance information (No in step S511), the distance simulation process is completed without reduction.

FIG. 16 shows an example of the reduction rate table.
The reduction rate table shown in FIG. 16 shows four levels of reduction rates. This reduction rate table shows the correspondence between the distance information and the reduction rate. That is, when the distance information is less than 2 m, the reduction rate of 90% is set. When the distance information is 2 m or more and less than 10 m, a reduction rate of 30% is set. When the distance information is 10 m or more and less than 50 m, a reduction rate of 10% is set. Further, when the distance information is 50 m or more, a reduction rate of 5% is set.
For example, when the value of the acquired distance information is 30 m, it corresponds to the column of 10 m or more and less than 50 m, so the reduction rate is set to 10%.

FIG. 17 is a flowchart showing details of the image processing for simulating the illuminance in step S52 (FIG. 14).
First, the image processing unit 16 determines whether the acquired usage environment information includes illuminance information (step S521). When it is determined in step S521 that the illuminance information is included in the usage environment information (Yes in step S521), the image processing unit 16 prepares a brightness change value associated with the value of the illuminance information in advance. The brightness change rate table is acquired (step S522). Then, the brightness value of the scan image and the correct image are changed with the brightness change value acquired in step S522 (step S523).
By performing this luminance value processing, the luminance simulation processing is completed. If it is determined in step S521 that the use environment information does not include the brightness information (No in step S521), the brightness simulation process is completed without changing the brightness value.

FIG. 18 shows an example of the brightness change rate table.
The brightness change rate table shown in FIG. 18 shows four levels of brightness change rates. This brightness change rate table shows the correspondence between the illuminance information and the brightness change rate. The brightness change rate here is a brightness change rate based on an image having a brightness of 1000 lux.
In the example of FIG. 18, when the illuminance information is less than 200 lux, the brightness change rate is set to 30%. When the illuminance information is 200 lux or more and less than 500 lux, the brightness change rate is set to 50%. When the illuminance information is 500 lux or more and less than 1000 lux, the brightness change rate is set to 80%. Further, when the illuminance information is 1000 lux or more, the brightness change rate is set to 100%.
For example, when the value of the acquired illuminance separation information is 600 lux, it corresponds to the column of 500 lux or more and less than 1000 lux, and the luminance change rate is set to 80%.

FIG. 19 shows an image for changing the brightness of an image.
Here, the original image is shown in FIG. 19A, the luminance change rate is set to 50%, and the image after the luminance change is shown in FIG. 19B. As can be seen by comparing the original image shown in FIG. 19(A) and the changed image shown in FIG. 19(B), by setting the luminance change rate to 50%, the image becomes dark as a whole.

FIG. 20 is a flowchart showing details of the image processing for simulating the color temperature in step S53 (FIG. 14).
First, the image processing unit 16 determines whether or not the acquired use environment information includes color temperature information (step S531). When it is determined in step S531 that the use environment information includes the color temperature information (Yes in step S531), the image processing unit 16 determines the color temperature change value associated with the value of the color temperature information. , A color temperature change rate table prepared in advance (step S532).
Then, the color temperature change values obtained in step S532 are used to change the color temperature values of the scan image and the correct answer image (step S533). By performing this color temperature processing, the color temperature simulation processing is completed. If it is determined in step S531 that the use environment information does not include color temperature information (No in step S531), the color temperature simulation process is completed without changing the color temperature.

FIG. 21 shows an example of the color temperature change rate table.
The color temperature change rate table shown in FIG. 21 shows four stages of color temperature change rates. The color temperature change rate table shows the correspondence between the color temperature information and the color temperature change rate. The color temperature change rate here is a color temperature change rate based on an image having a color temperature of 5000K.
In the example of FIG. 21, when the color temperature information is less than 3000K, the color temperature change rate is set to 25%. When the color temperature information is 3000 K or more and less than 4000 K, the color temperature change rate is set to 50%. When the color temperature information is 4000 K or more and less than 6000 K, the color temperature change rate is set to 100%. Further, when the color temperature information is 6000K or more, the color temperature change rate is set to 150%.
For example, when the value of the acquired color temperature information is 5000K, it corresponds to the column of 4000K or more and less than 6000K, and the color temperature change rate is set to 100%.

FIG. 22 shows an image for changing the color temperature of an image.
Here, the original image is shown in FIG. 22(A), the color temperature change rate is set to 50%, and the image after the color temperature change is shown in FIG. 22(B). The original image shown in FIG. 22(A) and the changed image shown in FIG. 22(B) are black and white on the drawing, so it is difficult to understand, but when comparing the actual color images, the color temperature change rate is 50%. It can be seen that the color of the image changes greatly when set to.

FIG. 23 is a flowchart showing details of the image processing for simulating the angle in step S54 (FIG. 14).
First, the image processing unit 16 determines whether the acquired usage environment information includes angle information (step S541). When it is determined in step S541 that the use environment information includes angle information (Yes in step S541), the image processing unit 16 deforms the scan image and the correct image into a trapezoid according to the angle. Mapping processing is performed (step S542). By performing this mapping process, the angle simulation process is completed. When it is determined in step S541 that the use environment information does not include angle information (No in step S541), the angle simulation process is completed without changing the angle.

As described above, according to the image inspection apparatus 10 according to the present embodiment, the defect detection process is performed after performing the image processing according to the usage environment of the printed matter, so that the printed matter is actually posted. It is possible to detect defects suitable for Therefore, as in the case of the first embodiment, when the defect is inconspicuous in the actual usage pattern of the printed matter, it is determined that there is no defect, and the time and effort for reprinting are saved. Will be able to.
In addition, in the case of the second embodiment, since the correction based on the distance, the illuminance, the color temperature, and the angle is performed as the image processing according to the usage environment, the actual usage environment is simulated. Defects can be detected, and defects can be detected at an appropriate level and state according to the actual usage environment.

<3. Modification>
In the second embodiment described above, the corrections based on the distance, the illuminance, the color temperature, and the angle are combined. However, by using any one or a plurality of requirements in these usage environments, Image processing may be performed according to the usage environment. Moreover, you may make it add the use environment of other requirements.
In particular, as an example of using printed matter, FIG. 1 shows an example in which a large printed matter is posted on the outer wall of a building. When applied to such a large printed matter, the usage environment of distance is important, For a user's direct viewing, image processing for distance becomes unnecessary. On the other hand, in a case where the user directly sees the printed matter up close, the environment such as the illumination for viewing the printed matter such as the illuminance and the color temperature becomes important, and the image processing about the illuminance and/or the color temperature becomes important. ..

Further, the level division, reduction rate, change rate, etc. in the tables described in the embodiments are also preferable examples, and are limited to the numerical values and level division states shown in the illustrated table. Not a thing. For example, when dividing the levels, the levels may be changed in at least two stages. Alternatively, the image processing state such as the reduction rate or the change rate may be changed steplessly according to the value such as the distance.

In the configurations shown in FIGS. 2 and 9, the image inspection apparatus 10 and the print information management server 20 are separate systems. On the other hand, the image inspection apparatus 10 may have a function as the print information management server 20. Alternatively, the image forming apparatus may incorporate the image inspection apparatus.
Further, in the configurations shown in FIGS. 2 and 9, the image inspection apparatus 10 is provided with the display unit (touch panel) for inputting the use environment information, but regarding the input of the use environment information by the worker, another terminal device is used. May be performed. The examples of the screens 100 to 400 for inputting the use environment information are merely examples, and other screen configurations may be used. For example, information on distance, illuminance, color temperature, and angle may be input on one screen.

DESCRIPTION OF SYMBOLS 10... Image inspection device, 11... Control part, 12... Storage part, 13... Display part, 14... Inspection part, 15... Communication part, 16... Image processing part, 20... Print information management server, 21... Operation system (OS) ), 22... Central control unit (CPU), 23... Storage unit, 24... Print information management software, 25... Communication unit, 30... Network, 100... Usage information input screen, 200... Illuminance information input screen, 300... Color temperature Information input screen, 400... Angle information input screen

Claims (7)

An information acquisition unit that acquires usage environment information that is information related to the environment in which the printed matter is used,
Based on the use environment information acquired by the information acquisition unit, after setting the defect detection level and the defect detection type, the scanned image of the printed matter and the correct image prepared in advance are compared, to the printed matter. An image inspection apparatus comprising: an inspection unit that performs an inspection for determining the presence or absence of a defect. The use environment information acquired by the information acquisition unit is information on the distance to browse the printed matter,
The image inspection apparatus according to claim 1, wherein the inspection unit reduces the correct image based on a distance indicated by use environment information. One of the defect detection types is a color misregistration detection process,
The image inspection apparatus according to claim 2, wherein the inspection unit excludes the process of detecting the color misregistration from inspection items when the distance at which the user browses the printed matter is larger than a predetermined threshold. The use environment information acquired by the information acquisition unit is information on the illuminance of a place where the printed matter is browsed,
The image inspection apparatus according to claim 1, wherein the inspection unit corrects the brightness of the correct image based on the illuminance indicated by the usage environment information. The use environment information acquired by the information acquisition unit is information on the color temperature of the place where the printed matter is browsed,
The image inspection apparatus according to claim 1, wherein the inspection unit corrects the color temperature of the correct image based on the illuminance indicated by the usage environment information. The use environment information acquired by the information acquisition unit is information on an angle at which the printed matter is browsed,
The image inspection apparatus according to claim 1, wherein the inspection unit maps the correct image to a corresponding angle based on an angle indicated by use environment information. Use environment information acquisition processing for acquiring use environment information, which is information related to the environment in which printed matter is used,
Based on the use environment information acquired by the use environment information acquisition process, after setting the defect detection level and the defect detection type, the image scanned the printed matter and the correct image prepared in advance are compared, the printed matter An image inspection method including an inspection process for performing an inspection for determining the presence or absence of a defect.