WO2023075538A1

WO2023075538A1 - Genuine product authentication method

Info

Publication number: WO2023075538A1
Application number: PCT/KR2022/016795
Authority: WO
Inventors: 이상훈
Original assignee: 주식회사 람다
Priority date: 2021-10-29
Filing date: 2022-10-31
Publication date: 2023-05-04

Abstract

The present invention provides a genuine product authentication method capable of determining whether a film including a reflective particle is a duplicate, by extracting a three-dimensional feature point from the film. A genuine product authentication method according to an embodiment of the present invention comprises the steps of: acquiring, from cameras, a first image and a second image captured by emitting light to an identification code at different angles; identifying a three-dimensional feature point of the identification code from the first image and the second image; and determining whether the identification code is a duplicate, on the basis of the feature point, wherein the identification code includes an authentication film having a predetermined thickness and including a plurality of reflective particles randomly disposed inside same.

Description

Activation method

An object of the present invention is to provide a genuine product authentication method capable of determining whether or not it is copied by extracting three-dimensional feature points from a film including reflective particles.

In general manufacturers, products are equipped with one-dimensional or two-dimensional identification codes for product classification or efficient distribution. However, existing 1- and 2-dimensional identification codes do not have a copy protection function, so it is difficult to cope with the distribution, sale, and change of origin of illegally copied products.

To prevent this, a method of indirectly determining whether an item is copied by attaching a new identification code that is difficult to duplicate to an item instead of a commonly used identification code and determining whether the identification code is duplicated has been proposed.

For example, there is a method of indirectly determining the authenticity of an article by determining the authenticity of a label printed with special ink or a label printed with a hologram, such as an expensive article, credit card, currency, or passport.

However, this method has a problem in that a new system must be introduced to determine whether the identification code is duplicated, and thus the existing production method and work method must be changed.

An object of the present invention is to authenticate the authenticity of a product based on the three-dimensional characteristics of a film.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention not mentioned above can be understood by the following description and will be more clearly understood by the examples of the present invention. It will also be readily apparent that the objects and advantages of the present invention may be realized by means of the instrumentalities and combinations indicated in the claims.

A genuine product authentication method according to an embodiment of the present invention for achieving the above object includes the steps of obtaining a first image and a second image taken by irradiating light at different angles to an identification code from a camera, the first image and identifying three-dimensional feature points of the identification code from the second image and determining whether or not the identification code is duplicated based on the feature points, wherein the identification code includes a plurality of reflections randomly disposed therein. It is characterized by including an authentication film having a predetermined thickness including particles.

The authentication film is characterized in that it is formed in the form of a film having a homogeneous density by adding homogeneous plate-shaped reflective particles to a molten resin.

Wherein the acquiring step comprises acquiring a first image and a second image respectively from a first camera and a second camera positioned differently under a single light emitting light at a fixed angle. do.

The obtaining may include acquiring a first image and a second image from the fixedly installed camera under first and second illumination radiating light at different angles.

The camera may generate the first image when only the first light is emitted, and generate the second image when only the second light is emitted.

The acquiring may include acquiring a first image and a second image sequentially photographed while moving a camera integrated with a light emitting light, respectively.

The identifying step includes identifying the brightness of the reflective particle at the same position on the first image and the second image as the 3D feature point, respectively, and the determining step includes the step of identifying the reflection identified in the first image. and determining that the particle is genuine if the brightness difference between the particle and the reflective particle identified in the second image is equal to or greater than a reference value.

The identifying step includes identifying the size of the reflective particle at the same position on the first image and the second image as the 3D feature point, respectively, and the determining step includes the step of identifying the reflection particle identified in the first image. When at least one of the particles and the reflective particles identified on the second image is larger than the actual size of the reflective particles, determining that the particles are genuine.

The identifying step includes identifying the size of the reflective particle at the same position on the first image and the second image as the 3D feature point, respectively, and the determining step includes the step of identifying the reflection particle identified in the first image. and determining that the particle is genuine if the size difference between the particle and the reflective particle identified on the second image is equal to or greater than a reference value.

The identifying step includes identifying a light spreading direction of the plurality of reflective particles appearing on the first image and the second image as the 3D feature point, and the determining step is based on an angle at which light is irradiated. and determining that the product is genuine when the light spreading direction is output accordingly.

The identifying step includes identifying the location of the reflective particle on the first image and the second image as the 3D feature point, and the determining step includes the location of the reflective particle identified in the first image and the location of the reflective particle on the second image. and determining that the second image is genuine if the difference in position of the reflective particles identified in the second image is greater than or equal to a reference value.

The present invention has an effect that it is possible to identify a forged product by a duplication method of an existing two-dimensional identification code by authenticating whether a product is genuine based on the three-dimensional characteristics of the film.

According to the present invention, by performing genuine product authentication without having a separate product authentication device, the user can determine whether the device is genuine or not.

In addition to the effects described above, specific effects of the present invention will be described together while explaining specific details for carrying out the present invention.

1 is a conceptual diagram schematically illustrating a genuine product authentication system according to the present invention;

2 is a conceptual diagram illustrating the concept of a three-dimensional identification code;

3 is a conceptual diagram illustrating the concept of reflective particles;

4 is a flowchart illustrating a genuine product authentication method according to the present invention;

5 to 7 are diagrams illustrating a structure for acquiring a first image and a second image from a camera;

8 is a diagram illustrating an example of comparing sizes of reflective particles on a first image and a second image;

9 is a diagram illustrating an example of comparing light spreading directions of reflective particles on a first image and a second image;

10 is a diagram illustrating an example of comparing positional differences of reflective particles on a first image and a second image;

The above objects, features and advantages will be described later in detail with reference to the accompanying drawings, and accordingly, those skilled in the art to which the present invention belongs will be able to easily implement the technical spirit of the present invention. In describing the present invention, if it is determined that the detailed description of the known technology related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

In this specification, first, second, etc. are used to describe various components, but these components are not limited by these terms, of course. These terms are only used to distinguish one component from another component, and unless otherwise stated, the first component may be the second component, of course.

In addition, in the present specification, when a component is described as being “connected”, “coupled” or “connected” to another component, the components may be directly connected or connected to each other, but other components may be present between each component. It should be understood that elements may be “interposed,” or that each element may be “connected,” “coupled,” or “connected” through other elements.

Also, singular expressions used in this specification include plural expressions unless the context clearly indicates otherwise. In this application, terms such as "consisting of" or "comprising" should not be construed as necessarily including all of the various components or steps described in the specification, and some of the components or some of the steps It should be construed that it may not be included, or may further include additional components or steps.

In addition, in this specification, when "A and / or B", unless otherwise specified, it means A, B or A and B, and when "C to D", it means a special opposite Unless otherwise specified, it means more than C and less than D

Referring to FIGS. 1 to 10, a genuine product authentication system and method according to an exemplary embodiment will be described in detail.

1 is a conceptual diagram schematically illustrating a genuine product authentication system according to the present invention.

2 is a conceptual diagram illustrating the concept of a three-dimensional identification code.

3 is a conceptual diagram illustrating the concept of reflective particles.

4 is a flowchart illustrating a genuine product authentication method according to the present invention.

5 to 7 are diagrams illustrating a structure for acquiring a first image and a second image from a camera.

8 is a diagram illustrating an example of comparing sizes of reflective particles on a first image and a second image.

9 is a diagram illustrating an example of comparing light spreading directions of reflective particles on a first image and a second image.

10 is a diagram illustrating an example of comparing positional differences of reflective particles on a first image and a second image.

Referring to FIG. 1, the activation system is a system for identifying an identification code 100 attached to a product (P) (eg, a picture, check, gift certificate, cash, product, etc.) requiring activation, and includes a camera 200, lighting (300) and server (400). However, the genuine product authentication system shown in FIG. 1 is according to an embodiment, and components constituting the invention are not limited to the embodiment shown in FIG. 1, and some components may be added, changed, or deleted as necessary.

The identification code 100 may store a variety of information capable of specifying the product P, such as the product P's name, serial number, and manufacturer, in a coded manner. This identification code 100 may have a one-dimensional (eg, UPC, EAN-13, EAN-8, KAN, etc.), two-dimensional (eg, QR code, PDF417, DATA MARIX code, etc.) or three-dimensional form. . However, the genuine product authentication method of the present invention described later may operate on the premise that the identification code 100 has a three-dimensional shape.

Referring to FIG. 2, the three-dimensional identification code 100 of the present invention is a form in which an authentication film 120 is further provided in the two-dimensional identification code 110, and the present invention identifies the three-dimensional identification code 100 It is possible to determine whether the various products (P) to which the identification code 100 is attached are duplicated.

Specifically, the three-dimensional identification code 100 may include an authentication film 120 further provided on the two-dimensional identification code 110, and the authentication film 120 has a predetermined thickness and is randomly disposed therein. It may include a plurality of reflective particles 130.

In one embodiment, the authentication film 120 may be formed in the form of a film having a homogeneous density randomly in a three-dimensional form by injecting the plate-shaped reflective particles 130 into a molten resin, and the resin is a thermoplastic resin It is desirable to be

In detail, the authentication film 120 is a mixture of synthetic resin and reflective particles 130 so that the reflective particles 130 can be arbitrarily disposed on the synthetic resin, and the mixture is a film having a predetermined thickness through extrusion, injection, or a film manufacturing process. can be manufactured with Through this manufacturing process, the plurality of reflective particles 130 may be disposed in different rotational angles, heights, positions, and the like within the authentication film 120 .

The half-particles 130 may be aluminum flakes, mica or thin sheets of thin synthetic resin pulverized into small pieces, or granules having a plurality of reflective surfaces, and may be formed in a size of 50 to 200 micrometers. can In addition, it is preferable that the half-character particle 130 is formed of a material resistant to heat so as not to be thermally deformed when mixed with resin.

In the present invention, the reflective particle 130 may be formed in a circular or hexagonal shape, and as the reflective particle 130 is formed in a circular or hexagonal shape, it is easy to extract a 3D feature point from the authentication film 120 due to its homogeneity and symmetry. There is an advantage to doing it. However, the shape of the reflective particle 130 is not limited thereto and may be formed in various shapes.

Since the plurality of reflective particles 130 reflect light, the three-dimensional feature point of the reflected light may be different depending on the position where the camera 200 photographs the reflective particle 130 or the angle at which the light irradiated from the lighting 300 is incident. there is.

The server 400 may identify the 3D feature point of the identification code 100 through the image taken by the camera 200 and perform genuine product authentication based on this.

At this time, the 3D feature point means a feature derived from an object formed in 3D, such as the reflective particle 130, and for example, the brightness, size, light spreading phenomenon and position difference of the reflected light may be the 3D feature point.

In detail with reference to FIG. 3 , the plurality of reflective particles 130 are fixed inside the authentication film 120 at random positions (x, y, z) and random postures (Φ, θ). At this time, if the thickness of the authentication film 120 is thinned within a range allowed by the measurement error, the random position of the reflective particle 130 may be calculated only with (x, y).

When the reflective particle 130 is i and the amount of light reflected by the reflective particle 130 is L _i , the amount of light L _i can be expressed by the following equation.

Here, x _i and y _i represent the position of the center point of the reflective particle 130, i in the authentication film 120, and Φ _i is the azimuthal angle of the reflective particle 130, i: the plane of the authentication film 120 position x _i , angle rotated relative to the vertical direction at the point y _i ), and θ _i is the polar angle of the reflective particle 130 (i) (polar angle: at the position x _i , yi point of the plane of the authentication film 120 represents the angle of inclination toward the direction of the plane relative to the direction perpendicular to the plane),

Based on the above theory, when the reflective particle 130 (i) has a homogeneous plate-like shape, since the front and back surfaces of the reflective particle 130 (i) are the same, θ _i (polar angle) is 0 degrees ≤ θ _i ≤ It can be formed within the range of 90 degrees. In addition, due to the simplicity of the reflective particles 130 (i), when the reflective particles 130 (i) having the same density are used, the server 400 can more easily identify three-dimensional feature points.

Conversely, when the reflective particles (130, i) are irregular or non-plate-shaped polyhedral, Φ _i (azimuth angle) and θ _{i (} polar angle) of the reflective particles 130 (i) are each -180 degrees < Φ _i ≤ 180 degrees, It may be formed within the range of 0 degrees ≤ θ _i ≤ 180 degrees. In this case, there are problems in that the sensitivity of the reflective characteristics of the reflective particles 130 (i) increases, making it difficult for the server 400 to identify 3D feature points, and the thickness of the authentication film 120 increases.

That is, when the reflective particle 130 (i) has a homogeneous plate-like shape and θi (polar angle) of the reflective particle 130 (i) is limited to 45 degrees ≤ θ _i ≤ 90 degrees, the server 400 identifies three-dimensional feature points The efficiency of can be higher in identification efficiency than any type of reflective particle 130 .

For example, when the identification code 100 is photographed with the camera 200 integrated with the lighting 300 based on the guide box provided by the genuine product certification system, the range of the shooting angle of the camera 200 is limited, and the irradiated The incident range of light may also be limited. Accordingly, only light irradiated within a certain angular range may have an effect on capturing an image.

Specifically, the range of the camera (200) shooting angle (Φ _C , θ _C ) is limited to 0 degrees ≤ θc ≤ 20 to 30 degrees relative to the vertical direction of the plane of the identification code 100, from the two lights (300) Assuming that the range of incident angles (Φ _L , θ _L ) of incident light is limited to the ranges of 0 degree ≤ θ _L ≤ 90 degrees and -180 ≤ Φ _L ≤ 180, respectively, the reflective particles within the range of 0 degree ≤ θ _i ≤ 45 degrees All light reflected from 130 may be reflected in a direction opposite to the camera 200 .

As a result, the reflective particles 130 located in the dark part of the identification code 100 are not output to the image, and the reflective particles 130 located in the white part appear in the form of black dots, so that the server 400 identifies the 3D feature point. There is a problem that is difficult to do.

Conversely, the reflective particle 130 located within the range of 45 degrees ≤ θ _i ≤ 90 degrees reflects light based on the angle of incidence of the light 300 and the posture (Φ, θ) of the reflective particle, so that the reflective particle 130 is photographed. 3D feature points can be identified in the image.

However, if the thickness of the authentication film 120 is manufactured based on the following equation, the polar angle of the reflective particle 130 may be formed such that θ _D degrees ≤ θi ≤ 90 degrees.

Here, t is the thickness of the authentication film 120, d is the size of the uniform plate-shaped reflective particles 130, and θ _D is the minimum polar angle to limit the posture of the reflective particles 130.

When the thickness of the authentication film 120 is formed in this way, all the reflective particles 130 in the authentication film 120 have an azimuth angle (Φ _i ) -180 degrees ≤ Φ _i ≤ 180 degrees, a polar angle (θ _i ) θ _D degrees ≤ θ It may be three-dimensionally located within the range of _i ≤ 90 degrees.

Referring back to FIG. 1 , the camera 200 may generate an image by photographing the identification code 100 . At this time, the camera 200 may be capable of wireless communication so that the image can be transmitted to the server 400 through the network, and replaced with a user terminal (eg, smart phone, tablet PC, etc.) equipped with the camera 200 function. It could be.

The lighting 300 irradiates light to the identification code 100, and may be provided integrally with the camera 200 and the user terminal or provided separately from the camera 200 and the user terminal.

4 shows a method for the activation system to perform activation. A genuine product authentication method according to an embodiment of the present invention includes the step of irradiating light to an identification code 100 at different angles and acquiring a first image and a second image taken from a camera 200 (S100); It may include identifying 3D feature points of the identification code 100 from the image and the second image (S200) and determining whether the identification code 100 is duplicated based on the feature points (S300).

However, the genuine product authentication method shown in FIG. 4 is according to an embodiment, and the steps constituting the invention are not limited to the embodiment shown in FIG. 4, and some steps may be added, changed, or deleted as necessary. .

Each step shown in FIG. 4 may be performed by the server 400 described above, and the server 400 includes application specific integrated circuits (ASICs), digital signal processors (DSPs), DSPDs ( digital signal processing devices), PLDs (programmable logic devices), FPGAs (field programmable gate arrays), controllers, processors, microprocessors, and micro-controllers. elements may be included.

Hereinafter, each operation step of the server 400 will be described in detail.

The server 400 may obtain a first image and a second image taken by irradiating light at different angles on the identification code 100 from the camera 200 (S100). In other words, the first image and the second image are images taken with the same identification code 100, but may be generated as different images according to a difference in the relative position of the lighting and the camera.

5 to 7 illustrate various embodiments in which the server 400 acquires a first image and a second image from the camera 200 .

Referring to FIG. 5 , in one example, the server 400 may acquire a first image and a second image in an environment in which one light 300 and two

cameras

201 and 202 are provided. The server 400 may obtain a first image and a second image respectively from the first camera 201 and the second camera 202 positioned differently under a single light 300 irradiating light at a fixed angle. .

Referring to FIG. 6 , in another example, the server 400 may obtain a first image and a second image in an environment in which two

lights

301 and 302 and one camera 200 are provided. The server 400 may obtain a first image and a second image from the camera 200 fixed under the first light 301 and the second light 302 emitting light at different angles. At this time, it is preferable that the camera 200 generates a first image when only the first light 301 emits light and generates a second image when only the second light 302 emits light.

Referring to FIG. 7 , in another example, a first image and a second image may be acquired by a single camera 200 . The server 400 may acquire the first image and the second image sequentially photographed while the camera 200 integrated with the lighting 300 for emitting light moves.

As described above, the camera 200 and the lighting 300 can be provided in various ways according to the user's convenience to perform the genuine product authentication method, thereby increasing the universality of the product authentication system and method.

The server 400 may first perform a process of normalizing the first image and the second image before identifying feature points in the acquired first and second images. Through this process, errors that may occur due to differences in environments in which each image is captured, such as differences in lighting 300, may be reduced.

First, the server 400 restores the two-dimensional code 110 by performing an image processing technique to remove salt and pepper noise from the first image and the second image, and the first image and the second image The types of products, data, and geometric information stored in the two-dimensional code 110 can be compared with each other.

If the information stored in the 2D code 110 of the first image and the second image matches, the server 400 may continue the activation process, and if the 2D code 110 of the first image and the second image ), the activation process can be terminated if the information stored in ) is inconsistent.

Next, the server 400 resizes the first image and the second image when the identification code 100 is bent, deformed, or rotated in the first image and the second image, and generates noise. The first image and the second image may be normalized by filtering . As a method for performing normalization, various techniques known in the field of image processing may be applied.

The server 400 extracts each of the reflective particles 130 in the process of processing the normalized first and second images, and uses a matching technique or a correlation technique to extract the reflective particles 130. It can be applied to calculate the reflective particles 130 having the same position in the first image and the second image.

In detail the process of calculating the same reflective particle 130, the server 400, based on the calculated value, the reflective particles 130 corresponding to each other in the first image (NI ₁ ) and the second image (NI ₂ ) A paired set Sm can be created.

At this time, the server 400 calculates the number n(NI 1 ) and n(NI ₂ ) of the reflective particles 130 appearing in the image (NI ₁ , NI ₂ ), respectively, and calculates the number n ( _Sm ) of elements of the set Sm. Probabilities (Pm ₁ , Pm ₂ ) of matching positions of the reflective particles 130 of each image (NI ₁ , NI ₂ ) may be calculated based on the following equation.

For example, if the first image NI ₁ and the second image NI ₂ are images with the same identification code 100, the probabilities Pm ₁ and Pm ₂ calculated by the server 400 are always first. It may have a value greater than or equal to the value Th1. If the calculated probabilities (Pm ₁ , Pm ₂ ) are calculated as values less than or equal to the first value Th1, the server 400 may determine that the first image and the second image are not genuine.

In detail, the probability (Pm1, Pm2) that the positions of the reflective particles 130 coincide in the first image and the second image in which the genuine identification code is taken is always equal to or greater than a certain value (Th1), respectively. The brightness difference of may appear randomly. That is, there are corresponding pairs of half-particles 130 on the first image and the second image, and the brightness difference between the reflective particles may be greater than or equal to a certain value Th2.

Conversely, if the brightness difference of the reflective particles 130 does not have a random value, or if there is no pair corresponding to the reflective particles 130 having a predetermined value (Th2) or more, the server 400 displays the first image and the second image. It can be determined that it is not a genuine product by determining the copied identification code (100).

The server 400 may generate a set Si by extracting only the reflective particles 130 having a certain value Th2 or more, and calculate a probability Pi based on the following equation.

In the case of photographing the genuine identification code 100, P _i can always be calculated as a value higher than a certain value (Th3). Even in the case of a counterfeit identification code 100, P _i is more than a certain value (Th3) due to the influence of light. Errors may occur in calculating values. To prevent this, the server may determine whether the product is genuine based on the 3D feature point.

Next, a process for the server 400 to identify 3D feature points will be described in detail.

The server 400 may identify 3D feature points of the identification code 100 from the normalized first image and second image (S200). Specifically, the server 400 may identify the brightness, size, light spreading direction, and location of the reflective particles 130 identified in the first and second images, respectively, as 3D feature points.

After identifying the 3D feature point, the server 400 may determine whether the identification code 100 is duplicated based on the feature point (S300).

Hereinafter, the step of identifying the 3D feature point by the server 400 (S200) and the step of determining whether the identification code 100 is duplicated based on the feature point (S300) will be described together.

For example, the server 400 may identify the brightness of the reflective particles 130 at the same positions on the first image and the second image as 3D feature points, respectively, and the brightness difference between the reflective particles 130 identified from each image. If the value is greater than or equal to the reference value, the identification code 100 may be determined to be genuine.

The light irradiated to the reflective particle 130 may be reflected with different brightness depending on the position and posture of the anti-particle 130 and output on an image. Such a phenomenon occurs when the reflective particles 130 are randomly arranged in the authentication film 120 and may be the most basic 3D feature point.

Conversely, since the copied identification code 100 is a two-dimensional plane, the size of the brightness of the reflective particles 130 does not change depending on the position of the camera 200 or the lighting 300, so that the three-dimensional feature point is not identified.

As a result, the server 400 may determine the identification code 100 as genuine when the difference in brightness between the reflective particles 130 of the first image and the reflective particles 130 of the second image is calculated to be greater than or equal to a preset reference value. there is.

As another example, the server 400 may identify the size of the reflective particle 130 at the same position on the first image and the second image as the 3D feature point.

In detail, the server 400 may determine that the image is genuine if at least one of the reflective particles 130 identified from each of the images a and b is larger than the actual size of the reflective particles 130 .

When light is irradiated to the reflective particle 130, the degree of reflecting light varies depending on the position and posture of the reflective particle 130, so that the reflective particle 130 on the first image (a) and the second image (b) ) may appear differently. Conversely, in the case of the copied identification code 100, the size of the reflective particles 130 on the first image (a) and the second image (b) does not change, so that a 3D feature point may not be identified.

Accordingly, the server 400 identifies a 3D feature point by using a phenomenon in which the image size of the reflective particle 130 appears larger than the actual particle size according to the light reflection characteristics when the reflective particle 130 reflects light. can

Referring to FIG. 8, the reflective particles 130 of the first image (a) and the second image (b) obtained from the light-irradiated identification code 100 may be output larger than the size of the actual reflective particle 130. there is. At this time, the server 400 may determine the identification code 100 as genuine. Specifically, the server 400 is genuine if the size of the reflective particles 130 on the first image (Fig. 7(a)) and the second image (Fig. 7(b)) is larger than the actual reflective particles 130. can be judged by

In addition, when comparing the same reflective particle 130 (circle) on the first image (a) and the second image (b), it can be seen that a difference in size has occurred, and the server 400 identifies the reflection from each image. If the size difference of the particles 130 is greater than the reference value, it can be determined as genuine. Specifically, the server 400 determines the identification code ( 100) can be judged as genuine.

In detail, the server 400 calculates the size difference between the pair of reflective particles 130 for the set (Si) element, extracts only elements having a size difference greater than a certain value (Th4), generates the set (Ss), and then Based on the equation, the probability Ps can be calculated.

That is, if the first image and the second image are images of genuine identification code 100, P _i is always calculated as a value equal to or greater than a certain value Th5, but P _i in the case of forged identification code 100 is 0 However, it can be calculated close to 0.

As another example, the server 400 may identify a 3D feature point based on the light spreading phenomenon of the plurality of reflective particles 130 appearing on the first image (a) and the second image (b), and the light If the light spreading direction is output on each image (a, b) according to the irradiation angle, it can be determined as genuine.

Referring to FIG. 9 , when the same reflective particle 130 (circle) is compared on the first image (a) and the second image (b), it can be seen that the direction in which light spreads is different.

This light spreading phenomenon occurs because the refractive index of the light reflected from the reflective particles 130 is different depending on the direction of the camera 200 and the lighting 300, and accordingly, the light reflected from the reflective particles 130 is scattered in one direction. can

Conversely, in the case of the copied identification code 100, the light spreading directions on the first image (a) and the second image (b) coincide, so that the three-dimensional feature point is not identified.

In detail, the server 400 determines whether there is a light spreading phenomenon with respect to the reflective particles 130 belonging to the image and the reflective particles 130 belonging to the image among the reflective particle 130 pairs of elements of the set (Ss). can If there is a light spreading phenomenon, the server 400 may calculate light spreading angles and averages (Am1, Am2) of the angles.

When the lighting 300 and the camera 200 are integrated, the light spreading direction is different between the first image and the second image, but the difference between the light spreading directions of the first image and the second image is calculated as a constant value Th6. can If there is no light spread in the reflective particles 130 or if Am1 and Am2 are the same, the server 400 may determine that the corresponding identification code 100 is forged or altered.

As a result, the server 400 causes a light spreading phenomenon in the first image (Fig. 9(a)) and the second image (Fig. 9(b)) according to the positions of the camera 200 and the light 300. If it occurs regularly in the direction of (300), it can be determined that the identification code (100) is genuine.

As another example, the server 400 may identify as a 3D feature point based on the position of the reflective particle 130 on the first image (a) and the second image (b), and identify each image (a, b). If the difference between the marked positions is more than the standard value, it can be judged as genuine.

Referring to FIG. 10 , when the same reflective particle 130 (circle) is compared on the first image (a) and the second image (b), it can be seen that the positions are different.

As shown in FIG. 2, the reflective particles 130 are randomly located inside the authentication film 120 having a predetermined thickness, and each reflective particle 130 has a height (D) located inside the authentication film 120. , d) is different, so the same reflective particle 130 on the first image (a) and the second image (b) can be photographed at different positions.

Referring again to FIG. 10 together, when the light 300 is irradiated on the reflective particles 130 included in the 3D identification code 100, the reflective particles ( 130) can be seen in different positions. At this time, it is preferable that the server 400 determines the positional difference by selecting the relatively dark reflective particles 130 on the first image (a) and the second image (b).

If the first image (I _1, a) is an image of the reflective particle (130, i) located at the height (D) at an angle of θ ₁ , Φ ₁ , the second image (I _2, b) is the height (D Assuming that the reflective particle 130 (i) located at ) is an image taken at an angle of θ ₂ , Φ ₂ , the server 400 is the first image (I _1, a) and the second image (I _2, b) The positional difference can be determined based on the following formula.

The positional difference calculated from the first image (I _1, a) and the second image (I _2, b) is wider as the photographing position between the two images (I _1, I ₂ ) is, and the two images (I _1, I ₂ ), the larger the shooting angle, the larger it is desirable.

Conversely, in the case of the copied identification code 100, since all of the reflective particles 130 are on a plane, a positional difference between the reflective particles 130 on the first image (a) and the second image (b) cannot occur, resulting in a three-dimensional Feature points are not identified.

In detail, the server 400 may calculate the central points of the reflective particles 130 of the set Sm, and stochastically identify elements having a predetermined value Th7 or more based on the difference between the central points. The server 400 may generate Sd, which is a set of elements having a certain value Th7 or more, and calculate a probability Pd based on the following equation.

If the two images are images with genuine identification code 100, Pd is always calculated as a value higher than a certain value (Th8), so the server 400 can determine the corresponding image as genuine, and the value of Pd is 0 or almost When calculated close to 0, the server 400 may determine that the identification code 100 is forged or altered.

As a result, the server 400 converts the identification code 100 to a genuine product when a positional difference between the reflective particles 130 occurs in the first image (Fig. 10(a)) and the second image (Fig. 10(b)). can be judged by

As a result of determining whether the identification code 100 is duplicated, the server 400 may output a notification to the user terminal when the identification code 100 is determined to be a duplicate.

As described above, the present invention has been described with reference to the drawings illustrated, but the present invention is not limited by the embodiments and drawings disclosed in this specification, and various modifications are made by those skilled in the art within the scope of the technical idea of the present invention. It is obvious that variations can be made. In addition, although the operational effects according to the configuration of the present invention have not been explicitly described and described while describing the embodiments of the present invention, it is natural that the effects predictable by the corresponding configuration should also be recognized.

Claims

Obtaining a first image and a second image taken by irradiating light at different angles to the identification code from a camera;

identifying three-dimensional feature points of the identification code from the first image and the second image; and

Determining whether or not the identification code is duplicated based on the feature point;

The identification code includes an authentication film having a predetermined thickness including a plurality of reflective particles randomly disposed therein.

Activation method.
According to claim 1,

The authentication film is formed in the form of a film having a homogeneous density by adding homogeneous plate-shaped reflective particles to a molten resin.

Activation method.
According to claim 1,

The step of obtaining

Acquiring a first image and a second image respectively from a first camera and a second camera positioned differently under a single illumination that irradiates light at a fixed angle.

Activation method.
According to claim 1,

The step of obtaining

Acquiring a first image and a second image from the fixedly installed camera under first and second illumination radiating light at different angles, respectively.

Activation method.
According to claim 4,

The camera generates the first image when only the first light is emitted, and generates the second image when only the second light is emitted.

Activation method.
According to claim 1,

The step of obtaining

Acquiring a first image and a second image sequentially photographed while a camera integrated with a light emitting light moves, respectively

Activation method.
According to claim 1,

The step of identifying

Identifying the brightness of the reflective particles at the same position on the first image and the second image as the three-dimensional feature point,

The judging step is

Determining that the brightness difference between the reflective particles identified in the first image and the reflective particles identified in the second image is greater than a reference value is a genuine product.

Activation method.
According to claim 1,

The step of identifying

Identifying the size of the reflective particle at the same position on the first image and the second image as the three-dimensional feature point,

The judging step is

If at least one of the reflective particles identified in the first image and the reflective particles identified in the second image is larger than the actual size of the reflective particles, determining that the reflective particles are genuine

Activation method.
According to claim 1,

The step of identifying

Identifying the size of the reflective particle at the same position on the first image and the second image as the three-dimensional feature point,

The judging step is

If the size difference between the reflective particles identified in the first image and the reflective particles identified in the second image is greater than a reference value, determining that the product is genuine

Activation method.
According to claim 1,

The step of identifying

Identifying light spreading directions of the plurality of reflective particles appearing on the first image and the second image as the three-dimensional feature points,

The judging step is

Determining that the light is genuine when the light spreading direction is output on the first image and the second image according to the angle at which the light is irradiated

Activation method.
According to claim 1,

The step of identifying

Identifying the location of the reflective particle on the first image and the second image as the three-dimensional feature point,

The judging step is

If the difference between the position of the reflective particle identified in the first image and the position of the reflective particle identified in the second image is greater than a reference value, determining that the product is genuine

Activation method.