JP6860151B2 - Printed matter reading inspection method and its equipment, and printed matter reading inspection software - Google Patents

Description

The present invention relates to a method for reading and inspecting printed matter, an apparatus thereof, and software for reading and inspecting printed matter.

In recent years, in Japan, the amount of crime damage caused by spoofing, such as special fraud and the opening of fraudulent deposit accounts that promote them, has reached a record high, threatening the safe and secure life of the people. In order to solve this problem, the revision of the Act on Prevention of Transfer of Criminal Proceeds is promoting stricter identity verification in specific private transactions, and online as represented by the Public Personal Authentication Service (JPKI). By promoting the spread of services that utilize the personal authentication platform, it is expected that it will be possible to reliably verify the identity of both face-to-face and non-face-to-face, and that spoofing damage will be reduced.

However, impersonators continue to attack by finding vulnerabilities in the existing identity verification process, so the situation remains unpredictable. In particular, in non-face-to-face transactions that do not use electronic signatures, a copy or photographed image is used instead of the original of the identity verification document, so the accuracy of determining whether or not it is a counterfeit product is reduced, and there is a high risk. It has been pointed out.

Identity verification documents refer to licenses issued by public institutions, and based on their notarization and attribution, the applicant's existence (not a fictitious person) and identity (of another person). It is a material to confirm that it is not spoofing). Attribution is generally said to be high for those who have a face photo on their identity verification documents, and their resistance to counterfeiting is not a basis. Moreover, even if the identity verification documents are sufficiently protected against counterfeiting, the authenticity of the identity verification documents themselves is guaranteed because the counterfeiting countermeasure function disappears in those copies and captured images. Is in a difficult situation.

As an anti-counterfeiting technique, the applicant of the present application has, for example, a first image line and a second image line arranged so as to face each other with a center as a boundary along the first direction, and a first direction. Image elements having a third image line and a fourth image line arranged so as to face each other with respect to the center along a second direction orthogonal to the image are arranged in a plurality of matrices at a constant pitch. The first line and the second line, and the third line and the fourth line in each line element are in a negative-positive relationship, and the first line or the second line is used. An application is filed for an anti-counterfeit print, characterized in that a first invisible image is formed by a stroke and a second invisible image is formed by a third stroke or a fourth stroke (eg,). See Patent Document 1).

In addition, the applicant has an image pattern consisting of one or more straight lines or curves in a straight line or a curved line, and the image of the portion not subjected to the latent image is a solid line, and the image of the portion to which the latent image is applied is a solid line. An image is a latent image in a printed matter composed of fixed-period break lines consisting of image lines having a shape in which the image lines are branched into a plurality of images at equal distances based on the basic line direction and the image lines are arranged at regular intervals. The image of the part with is the sum of the image areas of the part corresponding to one cycle consisting of the image part branched in the basic line direction and the non-image part, among the solid lines of the part without the latent image. By making it equal to the image area of the part of the latent image part that corresponds to the same length as one cycle consisting of the image part and the non-image part, it becomes invisible when copied, and the image is visually recognized before copying. An application has been filed for a printed matter in which the image lines constituting the image portion are larger than the image line area of a portion corresponding to the same length as one cycle consisting of an image portion and a non-image portion in the latent image portion (for example, a patent). Reference 2).

Further, as a method of performing a reading inspection of the anti-counterfeiting technology, the applicant has input the copy protection pattern as an image with an optical image input device, and binarized the input image signal to binarize it. Corresponds to the image processing unit that removes the corresponding pixel group by the image line of the part with the latent image on the input image due to the shrinkage of the image, and the image line of the part without the latent image obtained by the image processing unit. A reading inspection method and device consisting of an image determination unit that determines authenticity by recognizing, comparing, and collating the binary image shape remaining at the position, and a display unit that displays the result determined by the image determination unit. An application has been filed (see, for example, Patent Document 3).

However, there are various problems in these reading inspections, and improvement of reading accuracy and high-quality image extraction are required. A large number of image processing techniques for solving these problems have been filed. For example, the features of the input image are identified, the feature amount of the image is calculated according to the identification result, and the feature amount is input based on the calculated feature amount. Spatial filtering is applied to the image signal adaptively, and even if the input document contains continuous gradation images such as white ground character images, mesh dot images, and silver salt photographs, it is optimal for each image. A technique has been disclosed that can form a high-quality image that does not look strange with the input image by calculating the edge amount, which is a feature amount, and changing the strength of edge enhancement (for example,). See Patent Document 4).

Japanese Patent No. 4635160 Japanese Patent No. 3689786 Japanese Patent No. 3376406 Japanese Patent No. 3946410

However, for the anti-counterfeiting technology mentioned in References 1 and 2, it can be confirmed by the human eye by appropriately using a discriminator, or by changing the observation angle to an appropriate angle. Each observation condition is required, such as making or copying, and there is a possibility that individual differences may occur in the quality of visibility, and there remains a problem in the visibility condition.

Further, when the anti-counterfeiting technology is used for the identity verification document, it is required that the latent image can be read easily and more reliably regardless of whether the latent image is face-to-face or non-face-to-face.

In view of the above circumstances, it is an object of the present invention to provide a printed matter reading inspection method and an apparatus thereof capable of reading a latent image more reliably and easily, and a printed matter reading inspection software.

The method for reading and inspecting a printed matter of the present invention includes a step of photographing a region including a latent image of the printed matter to acquire image data, a step of smoothing the image data in one direction, and a step of smoothing the image data in one direction. The step of extracting an edge from the image data subjected to the smoothing process in one direction and the image data subjected to the process of extracting the edge are orthogonal to the one direction. It is characterized by including a step of performing a smoothing process in a direction and a step of displaying an image using the image data subjected to the smoothing process in a direction orthogonal to the one direction.

The printed matter reading inspection apparatus of the present invention performs an image capturing unit that photographs a region including a latent image of the printed matter to acquire image data, and smoothes the image data in one direction. Edges are extracted from the image data that has been smoothed in one direction, and the image data that has been subjected to the edge extraction process is oriented in a direction orthogonal to the one direction. An image processing unit that performs smoothing processing, an image display unit that displays an image using the image data that has been smoothed in a direction orthogonal to the one direction, and at least the image capturing unit is a printed matter. It is characterized by including a data storage unit for storing the image data acquired by photographing the image and the image data obtained by the image processing unit performing smoothing processing in a direction orthogonal to the one direction.

The printed matter reading inspection software for causing a printed matter reading inspection device including an image capturing unit, an image processing unit, an image display unit, and a data storage unit to execute the printed matter reading inspection method of the present invention is provided by the image capturing unit. , A step of capturing an area including a latent image of the printed matter to acquire image data, a step of smoothing the image data in one direction by the image processing unit, and the image processing. The image data in which an edge is extracted from the image data that has been smoothed in one direction by the unit and a process that extracts the edge by the image processing unit. to the image display by using a step of performing smoothing processing in a direction perpendicular to the one direction, by the image display unit, the image data subjected to smoothing in the direction were made perpendicular to the one direction And the data storage unit, at least the image data acquired by the image capturing unit capturing a printed matter and the image processing unit smoothed in a direction orthogonal to the one direction. It is characterized by including a step for storing the image data.

According to the printed matter reading inspection method of the present invention, the apparatus thereof, and the printed matter reading inspection software, a simple and more reliable latent image can be read regardless of whether it is face-to-face or non-face-to-face.

The block diagram which shows the structure of the reading inspection apparatus of the printed matter by embodiment of this invention. The flowchart which shows the structure of the reading inspection method of the printed matter by the same embodiment. The explanatory view which shows an example of the printed matter which has the phase modulation type latent image as an example of the latent image to be read in the reading inspection apparatus and method of the printed matter. An explanatory view showing a latent image image read by placing a lenticular lens on a printed matter having a phase modulation type latent image. The explanatory view which showed the information acquired by performing the edge extraction processing with respect to the phase modulation type latent image contained in the printed matter shown in FIG. The explanatory view which showed the image which performed the x-dimensional smoothing process on the printed matter shown in FIG. 3, and connected the image lines which form the same phase along the x direction. The explanatory view which showed the image which performed the edge extraction processing with respect to the image which performed the x-dimensional smoothing processing shown in FIG. It is explanatory drawing which showed the image which performed the y-dimensional smoothing process with respect to the image which performed the edge extraction process shown in FIG. 7. It is explanatory drawing which showed the image which performed the brightness correction with respect to the image which performed the y-dimensional smoothing process shown in FIG. An explanatory view showing a state in which a printed matter as shown in FIG. 3 is visually recognized when observed with the naked eye, and an image subjected to a series of processes as shown in FIG. 9 are observed with the naked eye. Explanatory drawing which showed the state which is visually recognized.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each embodiment, the same components are designated by the same reference numerals, and duplicate description will be omitted.

As shown in FIG. 1, the printed matter reading inspection device according to the present embodiment includes an image capturing unit 10, an image processing unit 20, a data storage unit 30, and an image display unit 40.

The image capturing unit 10 includes a camera, captures a region including a latent image formed on the printed matter, generates image data, and outputs the image data.

The image processing unit 20 is given the image data output from the image capturing unit 10 and performs the processing described later.

The data storage unit 30 is given and stores the image data output from the image capturing unit 10 and the image data processed by the image processing unit 20, and outputs the stored data to the image processing unit 20 as needed.

The image display unit 40 has a screen for monitoring, and is given data output from the image processing unit 20 to display an image such as a latent image and a processing result such as a true / false discrimination result.

The printed matter reading inspection method according to the present embodiment performs a latent image reading inspection using the printed matter reading inspection device described above, and includes the following steps as shown in FIG.

In step S10, the camera included in the image capturing unit 10 is activated.

In step S12, the camera of the image capturing unit 10 captures a region including the latent image formed on the printed matter and acquires image data. Image data is output from the image capturing unit 10.

The image processing unit 20 given the image data output from the image capturing unit 10 performs predetermined image processing in the following steps S14, S16, S18, S20, S22 and S24.

First, in step S14, the image data captured and given by the image capturing unit 10 is rotated by 90 degrees.

In step S16, the original image not rotated by 90 degrees (hereinafter referred to as "non-rotated image") and the image rotated by 90 degrees (hereinafter referred to as "rotated image") are each of, for example, 24-bit color. Color / black-and-white conversion is performed on the image data, for example, to 8-bit black-and-white image data. This process is performed in order to reduce the load of subsequent processes.

In step S18, image data including an 8-bit black-and-white non-rotated image and a rotated image is subjected to x-dimensional smoothing processing along, for example, the x direction as one direction.

In step S20, the phase modulation point is extracted from the image data that has been subjected to the x-dimensional smoothing process.

In step S22, y-dimensional smoothing processing is performed along the y direction orthogonal to, for example, the x direction as another direction different from one direction.

In step S24, the brightness correction process is performed on the image data that has been subjected to the y-dimensional smoothing process.

In step S26, the image data to which the brightness correction processing has been performed is output from the image processing unit 20. This image data includes two types of images obtained by processing a non-rotating image and a rotated image, respectively, and the image display unit 40 to which the image data is given is for a monitor included in the image display unit 40. Two types of images are displayed on the screen of.

In step S28, the image processing unit 20 determines whether or not all the latent images to be read and inspected have been read. If there is a latent image that has not been read yet, the process returns to step S12 and the processes of steps S12 to S26 are performed in the same manner. When all the latent images have been read, the process proceeds to step S30.

In step S30, the operation of the camera is stopped to end the reading inspection process.

Here, the latent image that can be read in the present embodiment is composed of image lines or halftone dots, and by emphasizing the outlines of the image lines or halftone dots, change points (edges) are extracted to obtain information. A wide range of readable images are included.

As an example of such a latent image, a phase modulation type latent image will be described with reference to FIG.

As shown in FIG. 3, the phase-modulated latent image is composed of linear image lines formed in different phases at regular intervals. With respect to such a latent image, a discriminator such as a lenticular lens in which fine semi-cylindrical shapes are arranged convexly on a sheet at regular intervals is superimposed so as to match the period of the latent image, as shown in FIG. As shown, a latent image as a latent image can be expressed.

However, it is not realistic to place a discriminator such as a lenticular lens on the latent image captured by the camera and displayed on the monitor screen, and the period of the captured latent image is not constant. In many cases, it does not match the cycle and cannot be read.

According to the printed matter reading inspection method and apparatus according to the present embodiment, the captured printed matter is subjected to the color (24-bit) / black-and-white (8-bit) conversion process and the x-dimensional smoothing process in steps S14 to S24, respectively. The latent image can be read by performing the phase modulation point extraction process, the y-dimensional smoothing process, and the brightness correction process.

In a phase-modulated latent image, the phase modulation point, that is, the position where the phase changes, is the position where the continuity of the image lines is interrupted in one direction in which the image lines are arranged, that is, the rate of change in brightness in the image is local. It is the position where the maximum value is obtained (hereinafter referred to as "edge"). In the latent image shown in FIG. 3, the portion where the continuity of the image line is interrupted and the phase is modulated in the horizontal direction in the figure corresponds to the edge.

An image as shown in FIG. 5 is obtained by specifying and extracting the edge position by first-order differentiating the brightness function l (x) with respect to such a latent image as shown by the following equation (1). Can be obtained.

Here, N is a neighborhood and x ₀ indicates the position of the phase modulation point.

However, images taken by a small digital camera, a smartphone, or the like often contain a lot of noise. Therefore, it may be difficult to read the latent image if only the edge extraction process by the first derivative described above is performed.

Therefore, before and after the edge extraction process by the first derivative, a spatial filter process is performed for the purpose of noise reduction.

There are various methods for spatial filtering. In the printed matter reading inspection method and its apparatus according to the present embodiment, the following processing requirements are set in consideration of the readability of the final latent image.

1) The spatial filter processing performed before the edge extraction processing suppresses the extraction of information other than the phase modulation points by the subsequent edge extraction processing, so that only the phase modulation points can be reliably extracted. Being a thing.

2) The spatial filter processing performed after the edge extraction processing removes unnecessary information other than the edges as much as possible without affecting the information about the edges as much as possible in the information extracted by the edge extraction processing performed before this. To be.

In order to satisfy the processing requirement of 1) above, it is indispensable to remove edges generated other than the phase modulation point.

By the way, in the image line configuration as shown in FIG. 3, even if the image lines forming the same phase are formed in the same phase, they take the form of a dividing line rather than a continuous straight line. That is, even on one dimension along one direction forming the same phase, edges are generated everywhere the image lines are divided.

For this reason, the strokes forming the same phase are filtered along one direction to extend the blurred legs at both ends of the strokes, and the strokes are connected to each other to remove unnecessary edges and extract. Noise can be suppressed by processing so that edges are generated only at the desired phase modulation point. Even if this filtering is performed, the information in the y direction orthogonal to the x direction does not change.

However, in the image data captured and acquired by the image capturing unit 10, the direction in which the image lines are arranged may be not only the x direction but also the y direction. In such a case, if the x-dimensional smoothing process along the x direction is performed collectively, the image lines constituting the latent image are affected and reading becomes difficult. Therefore, in the present embodiment, the above image processing is performed in parallel on the two types of images, the rotated image rotated by 90 degrees and the non-rotated image, and the two types of images are displayed on the monitor screen. In the following description, it is assumed that the image in which the image lines are arranged along the x direction is processed.

FIG. 6 shows an image in which image lines that are subjected to x-dimensional smoothing processing and form the same phase along the x direction are connected to each other.

However, when the x-dimensional smoothing process is performed, if the blurred legs generated at both ends of the image line extend too much along the x direction, interference with the latent image constituent region is expected. Therefore, it is necessary to adjust the weighting of the filter.

For the calculation of the weight, for example, a Gaussian function is used as in the following mathematical formula (2), and the kernel width (one-dimensional x) and the standard deviation σ of the weight are used as adjustment elements.

After the x-dimensional smoothing process, an edge extraction process is performed. The position of the edge is specified and extracted using the above formula (1).

Alternatively, the edge extraction process can be performed using an edge enhancement filter such as the Sobel filter shown by the following mathematical formula (3).

The image after the edge extraction process is as shown in FIG.

At the stage of performing the edge extraction process, fine edges are extracted everywhere in addition to the originally required phase modulation points. Further, it is considered that the image lines included in the images other than the latent image remain, which hinders the visibility of the latent image. In particular, the edge is formed along the y direction by performing the x-dimensional smoothing process before performing the edge extraction process.

Therefore, it is necessary to remove unnecessary noise by performing a y-dimensional smoothing process represented by the following mathematical formula (4) as a filter space process that satisfies the process requirement of 2) above.

（４）

(4)

Here, the weight is calculated by using the Gaussian function in the same manner as the x-dimensional smoothing process represented by the above equation (1), and using the kernel width (one dimension in the y direction) and the standard deviation σ of the weight as adjustment elements. To do.

The image after the y-dimensional smoothing process is as shown in FIG.

Even if the image signal after the y-dimensional smoothing process is output to the image display unit 40 and is attempted to be displayed on the monitor screen, the desired screen brightness and contrast are often not obtained.

Therefore, in consideration of the characteristics of the monitor, it is desirable to perform gamma correction as shown by the following mathematical formula (5) as brightness correction, for example.

Here, the value of γ is arbitrary.

The image after the brightness correction (gamma correction) is as shown in FIG.

Further, when the image is observed with the naked eye, it is visually recognized as shown in FIG. 10A before the processing, and the image obtained by extracting the latent image by a series of processing is as shown in FIG. 10B. The latent image can be clearly read.

The printed matter reading inspection software according to the present embodiment causes the printed matter reading inspection device according to the present embodiment to execute the printed matter reading inspection method according to the present embodiment, and operates as, for example, a printed matter reading inspection device. The computer may be made to execute the method of reading and inspecting the printed matter according to the present embodiment.

According to the present embodiment, since the captured latent image can be easily read by a simple operation, it is possible to perform simple and highly reliable identity verification regardless of whether it is face-to-face or non-face-to-face.

Although the embodiment of the present invention has been described above, this embodiment is presented as an example and is not intended to limit the technical scope of the invention. This novel embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. This embodiment and its modifications are included in the technical scope and gist of the invention, and are also included in the invention described in the claims and the equivalent scope thereof.

In the above-described embodiment, a case of reading a phase modulation type latent image is described as an example, and reading is performed by extracting a phase modulation point. However, the latent image that can be read by the above-described embodiment is not limited to the phase modulation type, and can be read by extracting the change points (edges) of the image lines or halftone dots that constitute the latent image. It can be widely applied to things.

For example, the image line pattern composed of one or more straight lines or curves described in Patent Document 2 described above is a solid line as an image other than a latent image, for example, the image of the portion to which the image is visualized. Then, the image lines of the portion to which the latent image is applied are branched into multiple lines at equal distances with reference to the basic line direction, and the fixed-period breaks are composed of the image lines having a shape in which the multiple branched image lines are arranged at regular intervals. In a printed matter composed of lines, the total of the image area of the part corresponding to one cycle consisting of the image part branched in the basic line direction and the non-image part is apparent in the image of the portion to which the latent image is applied. Of the solid lines of the imaged part, by making it equal to the image area of the part corresponding to the same length as one cycle consisting of the image part and the non-image part in the latent image part, it is invisible when copied. Therefore, the image lines constituting the image visually recognized before copying are latently larger than the image area of the portion corresponding to the same length as one cycle consisting of the image line portion and the non-image portion in the latent image portion. Even for an image, it is possible to extract and read a change point (edge) by emphasizing the outline of the image line.

Similarly, the aggregate pattern of the curved image lines described in Patent Document 3 described above is a latent image having, for example, a portion for drawing a manifest image as an image other than the latent image with a single line image and a latent image with at least two lines. The line that draws the latent image is expressed by the part that draws the image, and the total value of the line width is the same as the line width of the single line that draws the manifest image, and the line that draws the latent image from this single line is Even for printed matter that has a branching structure and prevents unauthorized copying by eliminating the image line that draws a latent image when copying, the change point (edge) is extracted by emphasizing the outline of the image line. It is possible to read it.

In addition, it is composed of a plurality of strokes arranged along one direction and having a bulge, and a plurality of strokes arranged along a different direction from one direction and having a bulge, and is visually recognized by tilting and observing the printed matter. Similarly, by emphasizing the outline of the image, the change point (edge) can be set for the printed matter in which a latent image is observed due to the occurrence of an image that is hidden by another image and an image that cannot be seen. It can be extracted and read.

Further, in the above-described embodiment, assuming that it is unknown whether the arrangement direction of the image lines constituting the latent image is the x-direction or the y-direction, the rotated image rotated by 90 degrees and the non-rotated image are combined. On the other hand, image processing is performed in parallel. However, it is not always necessary to perform processing on two types of images, and in particular, when the arrangement direction of the image lines is predetermined, processing may be performed on only one type of image.

10 Image capturing unit 20 Image processing unit 30 Data storage unit 40 Image display unit

Claims (18)

In the printed matter reading inspection method
A step of capturing an area including a latent image of the printed matter to acquire image data, and
A step of smoothing the image data in one direction and
A step of extracting an edge from the image data that has been smoothed in one direction, and a step of extracting an edge.
A step of smoothing the image data in which the edge extraction process has been performed in a direction orthogonal to the one direction, and a step of performing the smoothing process in the direction orthogonal to the one direction.
A step of displaying an image using the image data that has been smoothed in a direction orthogonal to the one direction, and
A method for reading and inspecting printed matter. A step of generating rotated image data rotated by 90 degrees with respect to the image data acquired by photographing the region including the latent image is further provided.
In each step of performing the smoothing process in one direction, the process of extracting the edge, and the smoothing process in the direction orthogonal to the one direction , the image obtained by photographing the region including the latent image. The method for reading and inspecting a printed matter according to claim 1, wherein in the step of performing the data and the rotated image data in parallel and displaying the image, two types of images are displayed. The image data obtained by photographing the region including the latent image is color image data.
Further provided with a step of converting the color image data into black and white image data.
In the step of performing the smoothing process in one direction, the black and white image data is subjected to the smoothing process.
The image data that has been smoothed in a direction orthogonal to one direction is further provided with a step of performing brightness correction processing.
The method for reading and inspecting a printed matter according to claim 1 or 2, wherein in the step of displaying the image, the image data subjected to the brightness correction process is used. The printed matter has a phase-modulated latent image in which strokes or halftone dots are arranged along the one direction or a direction orthogonal to the one direction.
The reading inspection of the printed matter according to any one of claims 1 to 3, wherein in the process of extracting the edge, the phase modulation point is extracted by emphasizing the outline of the image line or the halftone dot. Method. In the printed matter having at least one straight line or curved line pattern, the image lines in the area forming an image other than the latent image are composed of solid lines, and the image lines in the area forming the latent image are at least two lines. Consists of branched lines
The method for reading and inspecting a printed matter according to any one of claims 1 to 3, wherein in the process of extracting the edge, the edge is extracted by emphasizing the outline of the image line. The printed matter is provided with a plurality of strokes arranged along one direction and having a bulge, and a plurality of strokes arranged along a different direction from the one direction and having a ridge, and is visible when the printed matter is tilted and observed. A latent image is observed due to the occurrence of lines that are printed and lines that are not visible.
The method for reading and inspecting a printed matter according to any one of claims 1 to 3, wherein in the process of extracting the edge, the edge is extracted by emphasizing the outline of the image line. In a printed matter reading inspection device
An image capturing unit that captures an area including a latent image of the printed matter to acquire image data, and an image capturing unit.
The image data is smoothed in one direction, the image data that has been smoothed in one direction is processed to extract edges, and the edges are extracted. An image processing unit that performs smoothing processing on the obtained image data in a direction orthogonal to the one direction, and an image processing unit.
An image display unit that displays an image using the image data that has been smoothed in a direction orthogonal to the one direction.
At least, a data storage unit that stores the image data acquired by the image capturing unit by photographing a printed matter and the image data obtained by the image processing unit performing smoothing processing in a direction orthogonal to the one direction. ,
A printed matter reading and inspection device. The image processing unit generates rotated image data rotated by 90 degrees with respect to the image data acquired by the image capturing unit, smoothing the image in one direction, extracting the edge, and the one direction. When the smoothing process is performed in the direction orthogonal to the image processing unit, the image data acquired by the image processing unit and the rotated image data are performed in parallel with each other.
The printed matter reading inspection device according to claim 7, wherein the image display unit displays two types of images. The image capturing unit acquires color image data and obtains color image data.
The image processing unit converts the color image data into black and white image data, performs the smoothing process in one direction on the black and white image data, and smoothes the image data in a direction orthogonal to the one direction . Brightness correction processing is performed on the image data that has been subjected to the conversion processing.
The printed matter reading inspection device according to claim 7 or 8, wherein the image display unit uses the image data to which the brightness correction processing has been performed. The printed matter has a phase-modulated latent image in which strokes or halftone dots are arranged along the one direction or a direction orthogonal to the one direction.
The process according to any one of claims 7 to 9, wherein in the process of extracting the edge by the image processing unit, the phase modulation point is extracted by emphasizing the outline of the image line or the halftone dot. Printed matter reading inspection device. In the printed matter having at least one straight line or curved line pattern, the image lines in the area forming an image other than the latent image are composed of solid lines, and the image lines in the area forming the latent image are at least two lines. Consists of branched lines
The printed matter according to any one of claims 7 to 9, wherein in the process of extracting the edge by the image processing unit, the edge is extracted by emphasizing the outline of the image line. Inspection equipment. The printed matter is provided with a plurality of strokes arranged along one direction and having a bulge, and a plurality of strokes arranged along a different direction from the one direction and having a ridge, and is visible when the printed matter is tilted and observed. A latent image is observed due to the occurrence of lines that are printed and lines that are not visible.
The printed matter according to any one of claims 7 to 9, wherein in the process of extracting the edge by the image processing unit, the edge is extracted by emphasizing the outline of the image line. Inspection equipment. In the printed matter reading inspection software for causing a printed matter reading inspection device including an image capturing unit, an image processing unit, an image display unit, and a data storage unit to execute a printed matter reading inspection method.
A step of capturing an area including a latent image of the printed matter by the image capturing unit to acquire image data, and a step of acquiring image data.
A step of performing smoothing processing in one direction on the image data by the image processing unit, and
A step of performing a process of extracting edges from the image data that has been smoothed in one direction by the image processing unit, and a step of performing the process.
A step of performing a smoothing process in a direction orthogonal to the one direction with respect to the image data that has been processed to extract the edge by the image processing unit.
A step of displaying an image using the image data that has been smoothed in a direction orthogonal to the one direction by the image display unit.
At least, the image data acquired by the image capturing unit by photographing the printed matter and the image data obtained by the image processing unit performing smoothing processing in a direction orthogonal to the one direction by the data storage unit. Steps to store and
Software for reading and inspecting printed matter, which comprises. The image processing unit generates rotated image data rotated by 90 degrees with respect to the image data acquired by the image capturing unit, smoothing the image in one direction, extracting the edge, and the one direction. When the smoothing process is performed in the direction orthogonal to the image processing unit, the image data acquired by the image processing unit and the rotated image data are performed in parallel with each other.
The software for reading and inspecting a printed matter according to claim 13, wherein the image display unit displays two types of images. The image capturing unit acquires color image data and obtains color image data.
The image processing unit converts the color image data into black and white image data, performs the smoothing process in one direction on the black and white image data, and smoothes the image data in a direction orthogonal to the one direction . Brightness correction processing is performed on the image data that has been subjected to the conversion processing.
The software for reading and inspecting a printed matter according to claim 13 or 14, wherein the image display unit uses the image data to which the brightness correction processing has been performed. The printed matter has a phase-modulated latent image in which strokes or halftone dots are arranged along the one direction or a direction orthogonal to the one direction.
The process according to any one of claims 13 to 15, wherein in the process of extracting the edge by the image processing unit, the phase modulation point is extracted by emphasizing the outline of the image line or the halftone dot. Software for reading and inspecting printed matter. In the printed matter having at least one straight line or curved line pattern, the image lines in the area forming an image other than the latent image are composed of solid lines, and the image lines in the area forming the latent image are at least two lines. Consists of branched lines
The printed matter according to any one of claims 13 to 15, wherein in the process of extracting the edge by the image processing unit, the edge is extracted by emphasizing the outline of the image line. Inspection software. The printed matter is provided with a plurality of strokes arranged along one direction and having a bulge, and a plurality of strokes arranged along a different direction from the one direction and having a ridge, and is visible when the printed matter is tilted and observed. A latent image is observed due to the occurrence of lines that are printed and lines that are not visible.
The printed matter according to any one of claims 13 to 15, wherein in the process of extracting the edge by the image processing unit, the edge is extracted by emphasizing the outline of the image line. Inspection software.

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