JP2012121166A - Erratic collating inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an erratic collating inspection device capable of lowering an agreement rate between a reference image and a picked-up image.SOLUTION: The erratic collating inspection device is provided in a paper collator having a plurality of collating dies, images part of printing faces of signatures taken out one by one from the collating dies as an inspection image, and inspects erratic collating by comparing the inspection image with the reference image stored beforehand. The erratic collating inspection device includes: an imaging means imaging part of printing faces of signatures; a reference image setting means setting the plurality of reference images from target images obtained by cutting off part of the picked-up images taken by the imaging means; an erratic collation determination means determining erratic collation by comparing each of the plurality of reference images with the inspection image; a target image state calculation means calculating average density and contrast in the target image; and a target image state display means displaying the state calculated by the target image state calculation means. The plurality of reference images are selected based on display by the target image state display means.

Description

  The present invention relates to an irregularity inspection apparatus for inspecting irregularities when collating a form or the like.

2. Description of the Related Art Conventionally, as an inspection apparatus for booklets, missing pages, etc. (collectively referred to as "random pages" in this specification), a booklet inspection device using a CCD camera has been known.
For example, in a saddle stitching machine, a form stocked for each collating piece is taken out one by one by a form taking-out mechanism of each collating piece, and placed in order on a basket arranged in a conveying device (gathering chain). Formed as a bundle and conveyed to a downstream saddle stitcher.
Here, the CCD camera for checking the collation arranged for each collating piece takes the signature image, and compares the captured image with a pre-registered reference image to detect the presence or absence of the signature image. Then, it is performed to detect which collating frame has occurred in accordance with the detection signal of the image abnormality, the timing at which the CCD camera performs imaging, and the amount of signatures fed by the transport device (gathering chain).

Here, when detecting a disorder by comparing the captured image with a reference image registered in advance, if the area of the reference image is set wide, the difference from the captured image is only a slight difference. The coincidence rate between the captured image and the captured image cannot be lowered, and the coincidence rate must be set high in order to accurately detect disorder. On the other hand, if the area of the reference image is set to be narrow, there is a higher possibility of obtaining a similar captured image in other signatures, for example, signatures in adjacent collating frames (collated images between adjacent frames are often used). Due to the high similarity, the coincidence rate must be set high to detect erroneous insertion between adjacent frames.
However, since the captured image reflects distortion and bending that occur when the signature is conveyed, if the coincidence rate is set high as described above, this distortion and bending may cause false detection.

Therefore, in order to prevent erroneous detection even if the matching rate is set low, when setting the reference image area, a collation image with low similarity between adjacent collation frames is used as a reference image for the frame. It has been proposed to adopt. (Patent Document 1)
It has also been proposed to provide a setting means for setting the reference image area to a characteristic part of the signature. (Patent Document 2)

JP 2007-136925 A JP 2009-292088 A

However, as in Patent Document 1, it takes time and effort to compare signature images between adjacent collating frames and to set a collation image with low similarity as a reference image. The equipment is also expensive. In addition, since incorrect insertion of signatures into collating pieces does not occur only between adjacent collating pieces, in order to prevent failure of accurate random inspection, not only between adjacent pieces but also between all collating pieces. It is necessary to determine the similarity, and when the number of frames increases, it takes much time and time to set the reference image, and the cost for the device for that becomes high.
Further, as in Patent Document 2, even if the setting means for the characteristic portion is included, the same character string or design as the reference image or a similar character string or design exists in the paper image. In this case, if the operation is performed with a low match rate, there is a possibility that an inspection error that will be judged as a non-defective product may occur. Bending becomes a factor of false detection.

For this reason, the present invention is provided in a collating apparatus having a plurality of collating pieces, picks up a part of the print surface of the signature taken out from the collating piece one by one as an inspection image, and stores the inspection image and the image in advance. This is a randomness inspection device that inspects randomness by comparing with a reference image,
Imaging means for imaging a part of the print surface of the signature; reference image setting means for setting a plurality of reference images from a target image obtained by cutting out a part of the captured image captured by the imaging means; Each of the reference image and the inspection image, respectively, a disorder determination unit that determines disorder, and a target image state detection unit that detects an image state in the target image,
The plurality of reference images are selected based on a detection result in the target image state detection means.

With this configuration, it is not necessary to set the coincidence rate higher than necessary, so that a stable inspection result that is not affected by distortion, bending, disturbance light, etc. associated with the conveyance of the signature can be obtained.
Further, when selecting a reference image suitable for inspection from among the captured images, the selection can be made based on the detection result of the target image state detecting means for inspecting the target image state, and extraction of the characteristic portion in the target image can be performed. Since it is not necessary to set the reference image in detail, the setting time can be shortened and the operation can be performed quickly.
Furthermore, since it is not necessary to consider the extraction of a portion with low similarity between adjacent frames, the cost performance of the device itself is excellent.

  Further, the present invention is characterized in that the target image state detection means is means for calculating an average density and contrast in the target image, and has target image state display means for displaying a detection result by the target image state detection means. This is a random inspection apparatus.

With this configuration, the suitability evaluation of the target image as a reference image can be easily performed using two factors of average density and contrast. Therefore, it is necessary to strictly extract feature portions in the suitability evaluation as a reference image. Therefore, the setting operation of the reference image is easy.
In addition, since the reference image setting operation can be performed while observing the two factors of the average density and the contrast displayed on the target image state display means, the operation is easy.

  The present invention further includes reference image determination means for determining whether or not the detection result in the target image state detection means is within a predetermined range suitable as a reference image, and the reference image setting means includes the reference image setting means. The randomness inspection apparatus is characterized in that the target image determined to be appropriate as a reference image by the image determination means is selected as the reference image.

  With this configuration, the reference image setting unit selects the target image when the average density and contrast are within the predetermined ranges as the reference image, so the operator needs to perform the display while viewing the target image state display unit one by one. There is no.

  Further, in the present invention, when the target image having the average density or contrast outside the predetermined range is selected as the reference image by the reference image setting unit, a range for displaying that the selected reference image is outside the predetermined range A randomness inspection device characterized by having an outside selection display means.

  With this configuration, when the reference image selected and set by the operator is not suitable as the reference image, it is possible to display that the reference image is not suitable. Therefore, the reference image is appropriately set by prompting the operator to be alerted. be able to.

  In the present invention, the number of reference images set by the reference image setting unit is set to two, and the disorder determination unit calculates the two reference images set and the inspection images corresponding to the two reference images. In comparison, when the two inspection images coincide with each other at a predetermined coincidence rate or higher, it is determined that normal collation has been performed.

By comprising in this way, the stable test result which is not influenced by the distortion, bending, disturbance light, etc. accompanying conveyance of a signature can be obtained.
In addition, a quick operation can be performed when selecting a reference image suitable for inspection from among the captured images.
Furthermore, since it is not necessary to extract a portion having low similarity with adjacent frames or a feature portion in the target image, the cost performance of the apparatus itself is excellent.

  With this configuration, the present invention can set the matching rate (threshold value) between the reference image and the inspection image to be low even though the setting work of the reference image is easy, and affects the distortion and deflection of the signature. Test results that are not performed can be obtained.

The whole block diagram inspection device applied to the saddle stitch bookbinding line. The block diagram of the irregularity inspection apparatus in this invention. The external view of the piece disorder | corruption inspection part of the irregularity inspection apparatus in this invention. Explanatory drawing of the inspection timing of the irregularity inspection apparatus in this invention. The inspection flow figure of the random inspection apparatus in this invention. Explanatory drawing explaining the optimal range as a reference | standard image in this invention. Explanatory drawing explaining the relationship of the signature image in the present invention, a captured image, and a reference | standard image.

The first embodiment of the present invention will be described below using an example in which the first embodiment is applied to a collation apparatus.
When “captured image”, “target image”, “reference image”, and “inspection image” in the following description are defined, “captured image” A is a sheet (signature) B as shown in FIG. A part of the captured image is a part of the captured image and “target image” C is a determination target image for determining whether or not it is suitable as a reference image. The image “D” is an image that is selected and stored from the target images as being suitable as a contrast image for the disorderly collation inspection. The “inspection image” E is the folded image taken out from each collating piece. An image having a predetermined search area defined by a reference image position, which is a part of an image to be inspected, which is obtained by capturing an image of a part of the printing surface of the sword by the imaging unit.

As shown in FIG. 1, the collating apparatus 10 has a plurality of collating pieces 10-1 to 10-n each having a signature storing means 11, and a rotating shaft 13 extending in the horizontal direction, the rotation A drive unit 16 that rotationally drives the shaft 13, a signature table 12 that supports the signature storing means 11, a plurality of drums 14 arranged on the rotating shaft 13 corresponding to each signature storing means 11, and each collating piece It is comprised from the conveyance line (gathering chain) 17 which conveys the signature from 10-1 to n, and the collar (not shown) provided on this conveyance line 17. FIG.
When the rotary shaft 13 is driven to rotate, the signatures placed on the signature placing table 12 of each collating piece 10-1 to n are pulled out one by one by the claws of the drum 14 and placed on the conveyance line 17 Fall into.
The dropped signatures are stacked in order from each collating piece as they are conveyed, and a collation bundle is formed in which all the plural signatures are stacked in page order at the end of the collating apparatus 10.

As shown in FIG. 1 and FIG. 2, the random order inspection device 20 includes a piece random order inspection unit 20-1 to 20-n arranged one by one in each collating piece 10-1 to n and a network (I / O). The line control unit 30 is connected.
Each of the piece random inspection units 20-1 to 20-n has the same configuration, and has an image pickup unit 21, an inspection side control unit 22, an input operation unit 23, and a display unit 24 for imaging a signature. is doing.
The image pickup means 21 is an image pickup means composed of a CCD camera or the like for picking up an image of a part of the print surface of the signature drawn from the collating pieces 10-1 to 10-n.

  The inspection-side control unit 22 includes a collation image processing unit 22a that performs image processing such as cutting out a part of the captured image captured by the imaging unit and acquiring target image information, and the collation image processing unit 22a. Target image state detection means 22b for calculating the average density and contrast of the cut target image information, and whether or not the calculation result in the target image state detection means 22b is within a predetermined range suitable as a reference image A reference image determining unit 22c; a reference image setting unit 22d for selecting and storing as a reference image a plurality of target images for which the determination result in the reference image determining unit 22c is appropriate as a reference image; The tamper determination means 22e for comparing the image and the inspection image to determine the tampering, and storing the determination result together with various setting information in the tampering piece. Control such as stopping the collation apparatus 10 based on the inspection information storage means 22f, the inspection information from the disorder determination means 22e and the setting information from the input operation means 23, or the network (I / O) Via a piece control means 22g for outputting inspection information or the like to the line control unit 30.

The input operation means 23 sets an average density and contrast range allowed as a reference image to the inspection-side control unit 22, sets an acceptable matching rate between the reference image and the inspection image, or This is an input means for setting a condition for stopping the collation apparatus 10 when irregularity occurs continuously.
Further, the display unit 24 is a liquid crystal display unit that displays a captured image captured by the imaging unit 21, a target image specified from the captured image, a setting value input by the input operation unit 23, and the like. is there.
The piece random inspection units 20-1 to 20-n are accommodated in a case 28 shown in FIG. 3 except for the image pickup means 21, and the case 28 is operated by an operator so as to be operated by each operator. 1 to n are arranged in the vicinity.

The line control unit 30 is provided separately from each inspection-side control unit 22 in order to control the plurality of piece disorder checking units 20-1 to 20-n via a network (I / O). The whole system including the collation apparatus 10 and the random collation inspection apparatus 20 is controlled by one or a minimum number.
As shown in FIG. 2, the line control unit 30 includes standard time supply means 30b (a time server 30b-1 and a radio clock 30b-2) for supplying a standard time common to each collating piece 10-1 to n, and each collating piece. Input operation means 30d for inputting various setting information to the inspection side control section 22 and the like for each of 10-1 to n, the input operation by the input operation means 30d, and the operating state of each piece random inspection section 20-1 to n are displayed. Display means 30c, inspection information analysis / storage means 30e for collecting and analyzing and storing the inspection information from each piece check section 20-1 to n, start signal 31 from starter 15, pulse signal from encoder 32 and input It has a main control means 30a for controlling the line control unit 30 in response to an input signal from the operation means 30d.
The main control unit 30a controls the collation apparatus 10 and the collation inspection apparatus 20 on the basis of the setting information and the inspection information. When the (inspection information) is output, the collation apparatus 10 is automatically stopped, or the setting information is output to the piece collation inspection units 20-1 to 20-n based on the setting information by the input operation means 30d, When the operator operates the stop switch of the piece random inspection units 20-1 to 20-n, it has a function of forcibly stopping the entire collating apparatus 10.

The starter 15 generates a start signal 31 for each rotation of the drum 14, and a counter built in each inspection-side control unit 22 counts up the start signal 31 supplied through the main control means 30a. Therefore, the signature of each collating piece can be specified by the count number of this counter.
The encoder 32 generates a pulse signal in synchronization with the rotation of the drum 14, and the reference position (rotation angle position) of the claw provided on the drum 14 with respect to the signature storing means 11 is set by the pulse signal. The

The piece random inspection units 20-1 to 20-n are accommodated in a case 28 shown in FIG. 3 except for the image pickup means 21, and the case 28 is operated by an operator so as to be operated by each operator. 1 to n are arranged in the vicinity.
On the front side of the housing 28, together with the display means 24, an input operation means 23 is provided on an operation panel around the display means 24, and an upper portion thereof is used for notifying an inspection abnormality or the like. A red rotating lamp 25 is provided.
In addition, the display unit 24 displays the target image state display unit that displays the target image state based on the average density, contrast, and the like calculated by the target image state detection unit 22b in the display region 24 ′ on the right side of the display region for the captured image. When the average density or contrast of the target image selected as the reference image is outside the allowable range of the tampering determination preset by the input operation means 23 by the operator, an out-of-range selection is displayed. Display means 24b is provided.
Further, in addition to these displays, the display area 24 ′ includes the coincidence rate value determined by the disorder determination unit 22e and various numerical values set by the input operation unit, such as the number of allowable errors and the inspection mode. Displayed.

  In addition, the captured image area for the imaging unit 21 includes an inspection image area line 24c surrounding the inspection image area and a target image area line 24d surrounding the image area of the target image (the target image area line 24d is the target image). Is set as the reference image, the reference image area line 24d ′ surrounding the image area of the reference image is displayed. Here, the target image area line 24d is blue, and the reference image area line 24d ′ is red, so that they can be distinguished from each other by changing their line colors. When there is an area surrounded by a red line, it can be distinguished that the area is selected and set as a reference image.

The target image area line 24d is configured to be moved in the X and Y directions by operation of a target image movement switch 23a provided on the operation panel. At this time, the movement amount of the target image is set to a ratio of 10% with respect to the target image area in both the X and Y directions by pressing the target image movement switch 23a once.
When the target image area line 24d is moved in the imaging area by the operation of the target image movement switch 23a by the operator, the inspection image area line 24c surrounding the inspection image area is also in a predetermined positional relationship with the target image area line 24d. It is configured to move while keeping. The inspection image area line 24c is colored pink so that it can be distinguished from other area lines. At the time of random inspection, the inspection image surrounded by the inspection image region line 24c is compared with a preset reference image.

  Also, a captured image movement switch 23d is provided so that the position of the captured image in the signature can be adjusted. By operating the captured image movement switch 23d, the inside of the signature image is moved in the vertical direction (FIG. 3). In the vertical direction shown in FIG. Also in this case, each time the captured image movement switch 23d is pressed once, it is configured to move at a rate of 10% with respect to the captured image region in both the vertical direction.

Further, a reference image setting switch 23b for setting a target image surrounded by the target image region line 24d as a reference image is provided on the operation panel.
The reference image setting switch 23b has three switches including CH1 to CH3, and is configured such that the first to third reference images are set by pressing the switches CH1 to CH3, respectively. Has been. Each of the switches CH1 to CH3 is provided with lighting means 23b ′ composed of light emitting diodes of three colors (orange, green and red), and the reference image of the reference image is determined according to the emission color of the lighting means 23b ′. It is configured so that the setting status and the inspection status can be distinguished.
More specifically, when it is lit in orange, it indicates that the reference image has not been set yet, and when it is lit in green, the reference image is set or the set reference image is A state in which the inspection is in progress is shown, and when the light is red, the reference image being inspected has a coincidence rate abnormality and a collation error has occurred.

Next, in the first embodiment configured as described above, a procedure for setting a plurality of reference images and inspecting a disorder using these reference images will be described.
First, the setting of the reference image by the operator will be described.
When the operator operates the target image movement switch 23a of each piece check section 20-1 to 20-n to move the target image area line 24d within the captured image area, the operator moves within the target image area at the moved position. The average density and contrast are sequentially calculated by the target image state detection unit 22b, and the calculated values are displayed on the target image state display unit 24a.
Therefore, the operator observes the displayed calculated value, determines whether the calculated value is within a predetermined range appropriate as the reference image, and determines that the calculated value is appropriate as the reference image. Then, in order to register the target image surrounded by the target image area line 24d as a reference image, the reference image setting switch 23b (CH1) is pressed. Thereby, the target image is set as the first reference image, and the image area is displayed by the reference image area line 24d ′. The reference image setting position is such that the displayed target image area line 24d is changed to the reference image area line 24d ′ in accordance with the depression of the reference image setting switch 23b (CH1) (specifically, the target image setting line 23d). (The blue color of the image area line 24d has changed to the red color of the reference image area line 24d ′), and the reference image area line 24d ′ is fixedly displayed at that position. With this fixed display, the reference image area line 24d ′ does not move even when the inspection position movement switch 23a is operated. Further, the setting operation changes the lighting color of the lighting means 23b ′ of the reference image setting switch 23b (CH1) from the unset orange color to the set green color, and thus the setting of the first reference image is completed. You can confirm that.
If there is no area suitable for selection and setting as the reference image in the captured image area, the captured image movement switch 23d is pressed to change the captured image position, and the operation for selecting and setting the reference image is performed in the same manner. .

In this way, when the setting of the first reference image is completed, the operator next performs the same operation by the unset reference image setting switch 23b (CH2) that is lit in orange, and the second reference image is set. Set the reference image.
With this operation, two reference images are set in the captured image area.
Similarly, the third reference image may be set by the reference image setting switch 23b (CH3), but the work is omitted here.

Here, in the above-described operator work, while observing the calculated value displayed on the target image state display means 24a, it is determined whether or not the calculated value is within a predetermined range suitable as a reference image. Is done as follows.
In the present embodiment, the appropriate predetermined range is set based on the average density and contrast in the reference image area, as indicated by the hatched portion in FIG.
The average density is the average value of the brightness of all the pixels in the region, and the brightness of one pixel is composed of 0 to 63 levels. In contrast determination when determining disorder, it is necessary to pay attention to being too dark and too bright. Therefore, the optimum range is, for example, 20 to 45.
The contrast is determined by the difference between the darkest part of 10 pixels in the area and the brightest part of 10 pixels in the same area. If the difference in brightness is small, the image is not clear in the contrast determination. Therefore, the optimal range is, for example, 20 to 63.
As described above, in the present embodiment, the target image whose average density and contrast are both within the optimum range is suitable for the reference image.

Therefore, the operator moves the target image area line 24d from the captured image 24 to a position that seems to be suitable as the reference image by operating the inspection position movement switch 23a (and the captured image movement switch 23d as necessary). . Then, the average density and contrast at the position are confirmed by the numerical values of the target image state display means 24a. If the numerical values are within a numerical range suitable for the reference image, the position is set to the reference image setting switch 23b (CH1 to 3). Is set as the reference image position.
Even if the operator sets the reference image position in this way, if the set reference image is not in such an appropriate range, the setting is made to deviate from the appropriate range by the out-of-range selection display unit 24b on the operation panel. Is notified to the operator. By recognizing the notification, the operator cancels the reference image and resets the reference image as necessary, or sets the third reference image as necessary.

Next, a description will be given of the random inspection when two reference images are set in this way.
As shown in FIGS. 1 and 4, the starter 15 generates a start signal 31 for each rotation of the drum 14, and the piece control means 22g supplies the start signal 31 supplied through the main control means 30a. By counting up, it is possible to specify the signature in the piece irregularity inspection unit 20-1 to 20-n when the irregularity occurs.
The encoder 32 generates a pulse signal in synchronization with the rotation of the drum 14, and the reference position (rotation angle position) of the claw provided on the drum 14 with respect to the signature storing means 11 is determined by the pulse signal. Is set.

Then, as shown in FIG. 4, pulse counting is started at the timing when the start signal 31 is generated, and when a predetermined count weight (period A) is passed, an illumination LED (not shown) is applied to the signature 1. Is turned on for 50 ms to capture a signature image, and the captured image of the signature 1 is taken into the collation image processing means 22a at a predetermined timing. The collation image processing means 22a specifies the inspection image position based on a predetermined positional relationship corresponding to a preset reference image position from the captured image, and the inspection image information at the position and the above-described information. The reference image information set in advance is compared with the disorder determination unit 22e to determine the disorder. (Period B)
The determination result is output from the piece control means 22g to the main control means 30a via the network (I / O) and is also stored in the inspection information storage means 22f of each piece irregularity inspection unit. (Period C)
Further, the inspection result of the signature 1 is displayed as data in the display area 24 'on the right side of the display means 24 in each piece irregularity inspection unit.
The next signature 2 is also checked for randomness at the same timing (periods A, B, C) as the signature 1, and the inspection result is displayed in the same manner.

In the first embodiment, image acquisition is performed for one signature to compare the two reference images with the corresponding inspection images.
Therefore, as shown in FIG. 4, for one signature, image acquisition (b ') corresponding to the reference image position is performed together with image acquisition (b) performed corresponding to the period B (b'). ) To obtain two inspection images having a predetermined inspection area (Example 1), or more than the predetermined inspection area in Example 1 so as to include two reference image areas in the period B Whether one inspection image having a relatively large inspection area is acquired (Example 2).
Either Example 1 or Example 2 may be used, but in the case of Example 2, since the reference image is arranged close to each other and located in one inspection image region, the reference images are “deer” and “ In the case of approximation such as “tsuka”, there is a possibility that two reference images may be mixed and determined when making a comparison determination.
On the other hand, when two inspection images are acquired as in Example 1, such a confusion does not occur because the inspection images are separately compared, but even when the reference image is close, two inspection images Since the region is selected, it becomes a large inspection region as compared with Example 2, and there is a risk that the inspection processing is burdened.

Next, the coincidence rate determination for comparing the inspection image thus acquired with the reference image will be described.
In the present embodiment, as shown in FIG. 5, the image position of the image corresponding to the reference image in the inspection image region is specified in two stages, ie, a coarse search and a fine adjustment search, thereby improving efficiency.
First, an approximate position of an image corresponding to the reference image is specified by a coarse search. Specifically, one divided frame region obtained by dividing the inspection image region into 16 (the divided frame region is composed of 13 pixels in the vertical (Y) direction and 20 pixels in the horizontal (X) direction). The position where the coincidence rate with the reference image is maximized (the point where the overlay with the reference image is maximized) is detected while shifting by 2 pixels in the Y direction and 1 pixel in the X direction with a roughness of / 4 (S1). (S2).
Next, a fine search is performed around the coordinates obtained by the rough search without making the search roughness rough (S3), and the most coincident position is detected (S4).
Next, when the image position can be specified by the fine search, the shape of the image corresponding to the reference image in the divided frame region is determined (S5). Specifically, the halftone area is removed from the reference image, and only the bright part and the dark part are compared with the captured image to calculate the coincidence rate.
Next, this operation is repeated for the number of divided frames (S7), and the respective matching rates for the number of divided frames (16) are obtained, and the lowest value among them is set as the matching rate with the reference image (S8). ).

When the coincidence rate for one reference image is obtained in this way, the coincidence rate is similarly obtained for the other reference image.
Then, using the coincidence rate, the disorder determination by the disorder determination unit 22e is performed.
In the present invention, the acceptance / rejection determination based on the coincidence rate with respect to each reference image can be performed based on a threshold value set lower than in the past (80% in the embodiment using these two reference images). .
In this disorder determination by the disorder determination means 22e, the match rate with respect to the two reference images clears the threshold value set so low, and if it is determined to pass, there is no occurrence of disorder. And
On the other hand, when one or more are determined to be unacceptable, the determination is made as follows. In other words, if both of them fail, it is immediately determined that there is a disorder, and if one of them fails, it is determined that the disorder occurs on the condition that the state continuously occurs.

Next, a second embodiment of the present invention will be described.
In the second embodiment, a plurality of reference images can be set automatically.
As shown in FIG. 3, the housing 28 is provided with CH1 to CH3 of the reference image setting switch 23b, and the switch is configured to have an imaging channel selection switch function. This function is configured to work by pressing the automatic selection switch 23c.
When this function is activated, the reference image setting switches (imaging channel selection switches) CH1 to CH3 are switches for automatically selecting and setting each predetermined position in the imaging area of the signature as a reference image position. When the switch CH1 is pressed, the image area of the encoder counts t10 to t29 shown in FIG. 4 is selected as the reference image area at the encoder count timing in the imaging area, and when the switch CH2 is pressed, the image area of the encoder counts t30 to t49 is selected. Is selected as the reference image area, and when the switch CH3 is pressed, the image area of encoder counts t50 to t69 is selected as the reference image area.

At this time, if the average density and contrast of the image area thus selected are obtained by the target image state detection means 22b and the numerical values are not within the proper range shown in FIG. 6, the image capture position is set in the X direction or Y direction. The direction is automatically shifted by 10% with respect to the area of the region, and this shift is performed until it falls within the proper range.
Therefore, when the imaging channel selection switches CH1 to CH3 are pressed after the automatic selection switch 23c is pressed to change to the automatic selection mode, a reference image area is set for each pressed channel.
The setting position is displayed on the display unit 24 by the reference image region line 24d ′, and the setting state of the reference image is determined by the emission color of the lighting unit 23b ′ attached to each of the imaging channel selection switches CH1 to CH3. And inspection status can be distinguished.
In this embodiment, three imaging channel selection switches CH1 to CH3 are provided, but at least two may be used as in the first embodiment.
Further, the comparison determination between the reference image set in this way and the inspection image can be performed in the same manner as in the first embodiment.

As described above, in the present invention, it is possible to set the matching rate threshold of the reference image with respect to the inspection image to be low from about 90% to about 80%, so that the change in external light during inspection or Thus, it is possible to provide a collation inspection apparatus that can obtain a stable inspection result without affecting the bending or distortion of the paper during the collation conveyance.
In addition, it is possible to perform a quick operation in selecting a reference image suitable for inspection from among captured images, and it is not necessary to extract a portion having low similarity with adjacent frames, and it is possible to extract a feature portion in the target image. Therefore, it is possible to provide a collation inspection apparatus excellent in cost performance of the apparatus itself.

The present invention is not limited to the first or second embodiment described above, and various modifications are possible within the scope of the technical idea of the invention described in the claims. Examples of modifications include the following.
(1) In the above-described embodiment, one reference image position is set in each of a plurality (two) of imaging areas. However, the present invention is not limited to this, and as shown in Example 2 in FIG. A plurality (two) of reference image positions may be set in the area. However, when a plurality of reference image positions are set in one imaging area, the reference image may be approximated by the proximity of the reference image positions. Even if the image can be set, confirmation by the reference image determination means becomes more important.

(2) Although the collation target has been described as a monochrome image in the above embodiment, a collation inspection apparatus can be configured similarly for a color image as well.

(3) In the above embodiment, two reference images have been described. However, it is sufficient that the number is two or more. For example, when the number is three or more, the criterion for detecting the occurrence of disorder is changed. be able to. For example, in the case of three, any two reference images may have a predetermined matching rate.

(4) In the above embodiment, a method for obtaining a coincidence point at which the overlapped portion becomes the maximum, that is, a so-called residual matching method, is used as a pattern matching method between the reference image and the inspection image. A normalized correlation value method or the like can also be used.
In any case, it is the same in that the threshold value of the matching rate in pattern matching can be set lower.

(5) In the above embodiment, the error level (coincidence rate) is standardized to a predetermined level (80% as an initial value) in each reference image, but an error level is set for each reference image. It can also be configured to be able to. For example, when a character image area with clear contrast is selected as the reference image, the error level is set to a higher error level by setting the error level higher than the initial value. It can be. For this reason, the error level can be automatically changed according to the calculated value in the target image state detection means 22b.
Furthermore, the error level can be set lower according to the number of reference image settings. For example, in the case of three, if any two reference images may have a predetermined coincidence rate, the threshold of the predetermined coincidence rate can be set lower.

DESCRIPTION OF SYMBOLS 10 Collating apparatus 10-1-n Collating piece apparatus 20 Random collation inspection apparatus 21 Imaging means (imaging apparatus)
22a Collation image processing means 22b Target image state detection means 22c Reference image determination means 22d Reference image setting means 22e Randomity determination means 23 Input operation means 23b Reference image setting switch (imaging channel selection switch)
23c Automatic selection switch 24 Display means 24a Target image state display means 24b Out-of-range selection display means 28 Case 30 Line control unit

Claims (5)

A part of the printing surface of the signature that is provided in the collating apparatus having a plurality of collating pieces and is taken out one by one from the collating piece is picked up as an inspection image, and the inspection image is compared with a pre-stored reference image. An inspection device for inspecting random characters,
Imaging means for imaging a part of the print surface of the signature; reference image setting means for setting a plurality of reference images from a target image obtained by cutting out a part of the captured image captured by the imaging means; Each of the reference image and the inspection image, respectively, a disorder determination unit that determines disorder, and a target image state detection unit that detects an image state in the target image,
The irregularity inspection apparatus, wherein the plurality of reference images are selected based on a detection result in the target image state detection means.   2. The target image state detecting means according to claim 1, wherein the target image state detecting means is means for calculating an average density and contrast in the target image, and has target image state display means for displaying a detection result by the target image state detecting means. Random inspection device.   The reference image determination unit according to claim 1 or 2, further comprising a reference image determination unit that determines whether or not a detection result in the target image state detection unit is within a predetermined range suitable as a reference image. An irregularity inspection apparatus, wherein the target image determined by the reference image determination means to be appropriate as a reference image is selected as the reference image.   4. The caution display according to claim 1, wherein when the target image having the average density or contrast outside a predetermined range is selected as a reference image by the reference image setting means, the selected reference image is outside the predetermined range. An out-of-range selection display means is provided. 5. The number of reference images set by the reference image setting means is two according to claim 1, and the disorder determination means is configured to check the two reference images set and the inspection images corresponding to the two reference images. And the two inspection images are judged to have been correctly collated when both of them coincide with each other at a predetermined coincidence rate or more.

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