JP7613644B1 - PROGRAM, INFORMATION PROCESSING METHOD AND INFORMATION PROCESSING APPARATUS - Google Patents

Abstract

The program causes a computer to execute a process of acquiring an image of an object illuminated with light, detecting the position of the object from the image, detecting the irradiation position of the zeroth-order diffracted light from the image, and superimposing on the image an object for guiding the irradiation position of the zeroth-order diffracted light to a predetermined position on the object according to the detected position of the object and the irradiation position of the zeroth-order diffracted light.

Description

The present invention relates to a program, an information processing method, and an information processing device.

Holograms are used for brand protection and other anti-counterfeiting purposes. However, apart from experts who are familiar with hologram products, end users who have no knowledge of holograms cannot distinguish what state a hologram must be in to be genuine, making it difficult to determine its authenticity.

For example, Patent Document 1 discloses an authenticity determination support device for supporting the determination of authenticity of an anti-counterfeiting medium (such as a hologram) attached to an object to be subjected to authenticity determination, which generates and outputs image data that juxtaposes an image of the object and a correct answer image showing the light pattern emitted by the genuine anti-counterfeiting medium.

International Publication No. 2016/190107

On one aspect, the objective is to provide a program or the like that can effectively assist in determining authenticity.

In one aspect, the program causes a computer to execute a process of acquiring an image of an object illuminated with light, detecting the position of the object from the image, detecting the irradiation position of the zeroth-order diffracted light from the image, and superimposing an object on the image to guide the irradiation position of the zeroth-order diffracted light to a predetermined position on the object according to the detected position of the object and the irradiation position of the zeroth-order diffracted light.

In one aspect, it can effectively assist in determining authenticity.

FIG. 1 is an explanatory diagram showing an example of the configuration of an authenticity determination system. FIG. 2 is an explanatory diagram of a hologram portion. FIG. 2 is a block diagram showing an example of the configuration of a server. FIG. 2 is a block diagram showing a configuration example of a terminal. FIG. 11 is an explanatory diagram relating to a bright point induction process. FIG. 11 is an explanatory diagram relating to a bright point induction process. FIG. 11 is an explanatory diagram relating to a drawing process of a first rectangular area. FIG. 11 is an explanatory diagram relating to a drawing process of a first rectangular area. FIG. 11 is an explanatory diagram relating to a drawing process of a second rectangular area. FIG. 11 is an explanatory diagram relating to a drawing process of a second rectangular area. FIG. 11 is an explanatory diagram regarding a cut-out process of a hologram portion. FIG. 11 is an explanatory diagram regarding a cut-out process of a hologram portion. FIG. 11 is an explanatory diagram regarding a cut-out process of a hologram portion. FIG. 11 is an explanatory diagram regarding a cut-out process of a hologram portion. FIG. 11 is an explanatory diagram regarding an authenticity determination process. FIG. 11 is an explanatory diagram regarding an authenticity determination process. FIG. 11 is an explanatory diagram regarding an authenticity determination process. 11 is a flowchart illustrating an example of a processing procedure executed by the authenticity determination system. FIG. 11 is an explanatory diagram showing an overview of a second embodiment. 13 is a flowchart showing a processing procedure executed by the authenticity determining system according to the second embodiment;

The present invention will now be described in detail with reference to the drawings showing embodiments thereof.
(Embodiment 1)
1 is an explanatory diagram showing an example of the configuration of an authenticity determination system. In this embodiment, an authenticity determination system is described that guides a user to align the position of a bright spot (zeroth-order diffracted light) on a hologram and performs authenticity determination from a captured image in which the bright spot is superimposed on the hologram. The authenticity determination system includes a server 1 and a terminal 2. Each device is communicatively connected via a network N such as the Internet.

The server 1 is a server computer that performs various information processing and information transmission and reception. As described below, the server 1 performs processing to determine the authenticity of the authenticity determination target object 3 based on an image of the authenticity determination target object 3.

Terminal 2 is an information processing terminal used by a user of the system, such as a smartphone or tablet terminal. Terminal 2 is equipped with a light source (e.g., an LED (Light-Emitting Diode) light) that irradiates illumination light, and a camera that captures an image of a subject, and captures an image of an object 3 to be subjected to authenticity determination illuminated with illumination light. Terminal 2 transmits the captured image to server 1, which performs an authenticity determination.

In this embodiment, the object 3 to be determined for authenticity is provided with a hologram section 30. FIG. 2 is an explanatory diagram of the hologram section 30. As shown in FIG. 2, the hologram section 30 has a hologram portion in a circular ring shape, and when illuminated, the reflected light appears to diffract in a predetermined color. Specifically, when the bright spot (zeroth-order diffracted light (specularly reflected light)) of the illumination light is located at the center of the hologram section 30, orange wavelengths appear to be diffracted in the area above the bright spot, and green wavelengths appear to be diffracted in the area below the bright spot. As such a hologram, the hologram recording medium described in Japanese Patent Publication No. 4338124 can be used.

As in the modified example described below, the hologram is not limited to a hologram in which orange and green wavelengths are diffracted (a Lippmann hologram in which the wavelength is diffracted into multiple colors), but may be, for example, a hologram in which a single color wavelength is diffracted, or a hologram in which the wavelength is diffracted into two or more colors (multiple colors). Furthermore, the subject of authenticity determination may be any optical structure that allows for authenticity determination, and may be, for example, a diffraction grating or the like in addition to a hologram.

In addition, in this embodiment, the hologram is described as being arranged in a circular ring shape, but the shape and pattern of the hologram are not particularly important. Accordingly, the target position of the bright spot, which will be described later, may be changed to a position different from the center of the hologram section 30.

Meanwhile, an expert with knowledge of the hologram section 30 knows that the irradiation position of the zeroth-order diffracted light (position of the bright spot) should be aligned with the center of the hologram section 30 in order to determine authenticity, but an end user without such knowledge is expected to not know where to align the irradiation position of the zeroth-order diffracted light. Therefore, in this embodiment, a guide line 35 that connects the bright spot and the target position during imaging is drawn and superimposed on the display screen to assist the end user in easily performing imaging operations (see Figures 5A and B).

3 is a block diagram showing an example of the configuration of the server 1. The server 1 includes a control unit 11, a main memory unit 12, a communication unit 13, and an auxiliary memory unit .
The control unit 11 has one or more arithmetic processing devices such as a central processing unit (CPU), a micro-processing unit (MPU), a graphics processing unit (GPU), etc., and performs various information processing, control processing, etc. by reading and executing a program P1 stored in the auxiliary storage unit 14. The main storage unit 12 is a temporary storage area such as a static random access memory (SRAM) or a dynamic random access memory (DRAM), and temporarily stores data required for the control unit 11 to execute arithmetic processing. The communication unit 13 is a communication module for performing processing related to communication, and transmits and receives information to and from the outside. The auxiliary storage unit 14 is a non-volatile storage area such as a large-capacity memory or a hard disk, and stores the program P1 (program product) and other data required for the control unit 11 to execute processing.

The auxiliary storage unit 14 may be an external storage device connected to the server 1. The server 1 may be a multi-computer consisting of multiple computers, or may be a virtual machine virtually constructed by software.

In the present embodiment, the server 1 is not limited to the above configuration, and may include, for example, an input unit for accepting operational input, a display unit for displaying images, etc. The server 1 may also include a reading unit for reading portable storage medium 1a such as a CD (Compact Disk)-ROM or a DVD (Digital Versatile Disc)-ROM, and may read and execute the program P1 from the portable storage medium 1a.

4 is a block diagram showing an example of the configuration of the terminal 2. The terminal 2 includes a control unit 21, a main memory unit 22, a communication unit 23, a display unit 24, an input unit 25, an imaging unit 26, a light source 27, and an auxiliary memory unit 28.
The control unit 21 has one or more processors such as a CPU, and performs various information processing by reading and executing the program P2 stored in the auxiliary storage unit 28. The main storage unit 22 is a temporary storage area such as a RAM, and temporarily stores data necessary for the control unit 21 to execute arithmetic processing. The communication unit 23 is a communication module for performing processing related to communication, and transmits and receives information to and from the outside. The display unit 24 is a display screen such as a liquid crystal display, and displays images. The input unit 25 is an operation interface such as a touch panel, and accepts operation input from a user. The imaging unit 26 is a camera equipped with an imaging element such as a CMOS (Complementary Metal-Oxide-Semiconductor) sensor, and captures images. The light source 27 is a light source that irradiates illumination light, and is, for example, an LED light. The auxiliary storage unit 28 is a non-volatile storage area such as a hard disk, and stores the program P2 (program product) and other data necessary for the control unit 21 to execute processing.

The terminal 2 may also be provided with a reading unit that reads a portable storage medium 2a such as a CD-ROM, and may read and execute the program P2 from the portable storage medium 2a.

Figures 5A and 5B are explanatory diagrams relating to the bright spot guidance process. Figures 5A and 5B show the display screen of the terminal 2 during imaging, in which a guidance line 35 for guiding the bright spot position to a target position (center) on the hologram section 30 is superimposed (Figure 5A), and the hologram section 30 is cut out when the bright spot overlaps the target position (Figure 5B). An overview of this embodiment is provided below.

The terminal 2 captures an image of the hologram section 30 of the object 3 to be authenticated in accordance with a user's operation. The terminal 2 first detects a marker 31 that has been pre-attached to the hologram section 30 from the captured frame image. The marker 31 is a marker that has been added to enable detection of the position of the hologram section 30, and is, for example, an ARUco marker. The marker 31 is added to the diagonal of the rectangular hologram section 30. The terminal 2 detects the position of the hologram section 30 (object) by detecting the position of the marker 31.

Note that, in this embodiment, the marker 31 is described as an ARUco marker, but this embodiment is not limited to this. For example, the marker 31 may be a QR code (registered trademark). For example, the terminal 2 stores in advance the relative position between the QR code and the hologram section 30, detects the position of the QR code from the frame image, and detects the position of the hologram section 30 from the position of the detected QR code and a predefined relative position. In this way, a QR code may be adopted as the marker 31.

For example, relative position information between the QR code and the hologram section 30 may be embedded in the QR code itself, and the terminal 2 may be able to detect the position of the hologram section 30 by reading the relative position information.

Based on the position of the detected marker 31, the terminal 2 superimposes and displays a first rectangular area 32 that is drawn to surround the hologram section 30 and a second rectangular area 33 that is drawn in the center of the hologram section 30, i.e., at the target position of the bright point.

6A and 6B are explanatory diagrams relating to the drawing process of the first rectangular area 32. The terminal 2 calculates the coordinates of the midpoint C based on the positions of vertices A and B of the marker 31 arranged at diagonal corners of the hologram unit 30. The terminal 2 also calculates the distance _ABX in the X direction and the distance _ABY in the Y direction between the vertices A and B. The terminal 2 then calculates the diagonal coordinates DA0 and DB0 of a square with the midpoint C at its center and the longer of _ABX and _ABY as one side. The terminal 2 draws the square with DA0 and DB0 as its diagonal corners as the first rectangular area 32.

7A and 7B are explanatory diagrams relating to the drawing process of the second rectangular area 33. Terminal 2 calculates the coordinates of midpoint C and distances _ABX and _ABY in the same way as when drawing the first rectangular area 32. Terminal 2 then calculates the shorter long side by multiplying the longer of _ABX and _ABY by a predetermined magnification (e.g., 0.2 times), and calculates the diagonal coordinates DA1 and DB1 of a square with the calculated long side as one side and centered on midpoint C. Terminal 2 draws the square with DA1 and DB1 as diagonals as the second rectangular area 33.

5A and 5B for further explanation. Terminal 2 further detects the position of the bright spot (the irradiation position of the zeroth-order diffracted light) from the frame image, and displays a circular bright spot area 34 corresponding to the range of the bright spot (the irradiation range of the zeroth-order diffracted light) superimposed on the frame image.

The bright spot referred to here is what is generally called a blown-out highlight in a captured image. For example, a bright spot is not an isolated point, but a roughly circular continuous area that includes a certain area in the captured image where the gradation of the highlights has been lost.

For example, terminal 2 creates a brightness histogram based on the brightness and saturation of the image, and calculates a brightness threshold value for bright spot detection. Terminal 2 detects pixels whose brightness is equal to or greater than the threshold value and whose saturation is equal to or less than a predetermined threshold value as bright spot dots, and detects continuous areas where bright spot dots are continuous. In addition to the above detection method, for example, in the case of an image with 8-bit RGB values, dots whose all three colors are equal to or greater than a predetermined value, such as 250, may be detected as bright spot dots.

The terminal 2 extracts the area with the maximum average brightness from the detected continuous area or areas as the area of the zeroth-order diffracted light. The terminal 2 sets the center of gravity of the extracted area as the center of the bright spot. The terminal 2 assumes that the final bright spot area 34 is circular, and calculates the radius from the area (number of dots) of the area of the zeroth-order diffracted light. The terminal 2 draws the bright spot area 34 based on the calculated radius and the center of the bright spot identified above.

Then, based on the position of the bright spot detected above and the position of the hologram section 30, the terminal 2 superimposes and displays a guiding line 35 for guiding the position of the bright spot (the irradiation position of the zeroth-order diffracted light) to a predetermined position on the hologram section 30 (object). Specifically, the terminal 2 draws an arrow-shaped object extending from the center of the bright spot region 34 to the center of the second rectangular region 33.

Note that an arrow is an example of a guiding line 35 (object), and the shape of the object corresponding to the guiding line 35 is not limited to an arrow. For example, the terminal 2 may simply draw a straight line.

The user refers to the guiding line 35 and operates the terminal 2 so that the center of the bright spot area 34 overlaps with the second rectangular area 33. When the position of the bright spot overlaps with the target position on the hologram, the terminal 2 cuts out the image area corresponding to the hologram section 30 from the frame image. Specifically, when the center of the bright spot area 34 is located within the coordinate range of the second rectangular area 33, the terminal 2 executes the cut-out process.

Figures 8 to 10 are explanatory diagrams regarding the cut-out process of the hologram section 30. Figures 8 to 10 show the details of the cut-out process of the hologram section 30.

First, terminal 2 calculates vector sAB by multiplying the diagonal line between vertices A and B of marker 31 by a predetermined magnification (e.g., 0.1 times) as shown in Figure 8. Terminal 2 calculates vertices sA and sB by extending vertices A and B by subtracting or adding vector sAB to vertices A and B.

Note that expanding the area (vertices A and B) is an optional process as long as the server 1 can cut out an image area large enough to properly recognize the hologram section 30.

Next, terminal 2 calculates vector sAsB connecting vertices sA and sB, and calculates vector V which is half of the calculated vector sAsB, as shown in Figure 9A. Terminal 2 calculates four vertices S0 to S3 based on the coordinates of midpoint C and the calculated vector V, as shown in Figure 9B.

As shown in Figure 10, terminal 2 calculates the rotation angle θ of the image from the coordinates of vertex S0 and applies a rotation process to the image. Terminal 2 uses S0 to S3 as vertices and cuts out the image area that has been rotated as the image of hologram section 30.

Figures 11 and 12A and B are explanatory diagrams relating to the authenticity determination process. The terminal 2 transmits the cut-out image to the server 1, which performs an authenticity determination. Figure 11 illustrates an overview of the authenticity determination process. Figures 12A and B illustrate how a bright spot region 34 is detected when performing an authenticity determination (Figure 12A), and how an area based on the center of gravity of the bright spot region 34 is divided into multiple regions (Figure 12B).

First, server 1 converts the image (RGB image) acquired from terminal 2 into an HSV image represented by hue, saturation, and brightness. Server 1 then detects a circular image area corresponding to the range of the bright spot (the irradiation range of the zeroth-order diffracted light) in a manner substantially similar to that in which terminal 2 identifies bright spot area 34. That is, server 1 detects bright spot dots whose brightness is equal to or greater than a threshold value and whose saturation is equal to or less than a threshold value, and detects continuous areas in which bright spot dots are continuous. Server 1 detects bright spot area 34 by setting the center of gravity of the detected continuous area as the center of the bright spot and calculating the radius of the circular area according to the area of the continuous area. As a result, a circular bright spot area 34 is detected, as shown in FIG. 12A.

Next, server 1 divides the area based on the center of gravity of detected bright spot area 34 into multiple areas. Specifically, as shown in FIG. 12B, server 1 divides the area into two areas, with the area above the bright spot designated as orange detection area 36 and the area below the bright spot designated as green detection area 37. Server 1 calculates distance L by multiplying the radius of bright spot area 34 by a predetermined factor (e.g., 1.5 times), and excludes the distance range extended in the Y direction by distance L from the center of bright spot area 34. Server 1 divides the remaining area into upper and lower areas, with the upper area designated as orange detection area 36 and the lower area designated as green detection area 37.

Server 1 performs authenticity determination by determining whether or not a specified color component is present in each divided area at a ratio equal to or greater than a specified value.

Specifically, the server 1 detects pixels of orange and green color components by comparing the hue, saturation, and brightness of the HSV image with respective thresholds, and determines whether the number of detected pixels is equal to or greater than a predetermined value. The server 1 counts pixels from the orange detection area 36 whose hue is within a predetermined numerical range and whose saturation and brightness are equal to or greater than a predetermined threshold as orange dots. Similarly, the server 1 counts pixels from the green detection area 37 whose hue is within a predetermined numerical range and whose saturation and brightness are equal to or greater than a predetermined threshold as green dots. The server 1 determines whether the number of dots counted in each area is equal to or greater than a predetermined value. If it is determined that the number of dots in both areas is equal to or greater than the predetermined value, the server 1 determines that the authenticity determination target object 3 is genuine.

In the above, it is simply determined whether the number of dots of the target color component is equal to or greater than a predetermined value, but the present embodiment is not limited to this. For example, the server 1 may make a determination based on the ratio (area ratio) between the area of each detection region and the number of dots (number of pixels).

Specifically, the server 1 detects the number of orange dots from the orange detection area 36 in the same manner as described above, and calculates the area of the orange detection area 36. The server 1 then determines whether the value (area ratio) obtained by dividing the number of orange dots by the area of the orange detection area 36 is equal to or greater than a predetermined value. The server 1 similarly calculates the area ratio for the green detection area 37, and determines whether the area ratio is equal to or greater than a predetermined value. If the server 1 determines that the area ratio is equal to or greater than the predetermined value in both the orange detection area 36 and the green detection area 37, it determines that the authenticity determination target object 3 is genuine.

In this way, by making a judgment based on the area ratio, appropriate judgment is possible even if the detection area becomes extremely narrow or the image size changes.

As described above, the server 1 performs an authenticity determination by determining whether or not orange and green color components are present in a ratio equal to or greater than a predetermined value in the orange detection area 36 and the green detection area 37. The server 1 outputs the determination result to the terminal 2, and the terminal 2 displays the determination result.

In the above, authenticity was determined by converting the colors that appear as a result of diffraction of the wavelengths in the orange detection area 36 and the green detection area 37 into HSV, but authenticity may also be determined based on the ratio of the luminance values of each RGB color rather than the color components in the HSV color space.

Specifically, the server 1 may perform the authenticity determination by determining whether the ratio of the luminance values of the RGB colors of each dot (pixel) in each detection area (orange detection area 36 and green detection area 37) is a predetermined ratio. More specifically, the server 1 may perform the authenticity determination by determining whether the number of dots (number of pixels) in which the luminance values of the RGB colors are a predetermined ratio in each detection area is equal to or greater than a predetermined value. Alternatively, the server 1 may perform the authenticity determination by determining whether the area ratio obtained by dividing the number of dots in which the luminance values of the RGB colors are a predetermined ratio in each detection area by the area of the detection area is equal to or greater than a predetermined value. The server 1 performs the authenticity determination by detecting the number of dots in which the luminance values of the RGB colors of each dot in the detection area are equal to or greater than a predetermined value, for example, in the orange detection area 36, the ratio of the luminance values of R:G:B is approximately 1:0.5±0.1:0±0.1.

As described above, according to this embodiment, by displaying the guiding line 35 when imaging the hologram section 30, it is possible to guide the bright spot (zeroth order diffracted light) to the correct position, thereby providing ideal assistance in determining authenticity.

In addition, according to this embodiment, the server 1 divides the image of the hologram section 30 into multiple regions and determines whether a predetermined color component is present in each region at a ratio equal to or greater than a predetermined value (or whether the ratio of the luminance values of each RGB color of each dot in each region is a predetermined ratio), thereby enabling automatic authenticity determination.

13 is a flowchart showing an example of a process performed by the authenticity determination system, and the process performed by this system will be described with reference to FIG.
The control unit 21 of the terminal 2 starts capturing an image of the hologram unit 30 (object) in accordance with an operation by the user (step S11). The control unit 21 acquires a frame image capturing the image of the hologram unit 30 (step S12).

The control unit 21 detects the marker 31 that has been previously assigned to the hologram unit 30 from the frame image (step S13). The control unit 21 also detects the position of the bright spot (the irradiation position of the zeroth-order diffracted light) from the frame image (step S14).

Based on the detected positions of the marker 31 and the bright spot, the control unit 21 superimposes on the frame image a guiding line 35 (object) for guiding the bright spot to a predetermined position on the hologram unit 30 (step S15). Specifically, based on the position of the marker 31, the control unit 21 identifies and superimposes a first rectangular area 32 surrounding the hologram unit 30 and a second rectangular area 33 to which the zeroth-order diffracted light should be irradiated. Furthermore, based on the saturation and brightness of the frame image, the control unit 21 identifies and superimposes a bright spot area 34 corresponding to the irradiation range of the zeroth-order diffracted light. The control unit 21 then superimposes a guiding line 35 extending from the center of the bright spot area 34 to the center of the second rectangular area 33.

The control unit 21 determines whether the position of the bright spot (the center of the bright spot area 34) overlaps with a predetermined position (the second rectangular area 33) on the hologram unit 30 (step S16). If it is determined that they do not overlap (S16: NO), the control unit 21 returns the process to step S12.

If it is determined that there is overlap (S16: YES), the control unit 21 cuts out an image area corresponding to the hologram unit 30 from the frame image (step S17). The control unit 21 transmits the cut-out image to the server 1 (step S18).

The control unit 11 of the server 1 converts the image of the hologram unit 30 acquired from the terminal 2 into an HSV image (step S19). The control unit 11 detects a circular bright spot region 34 based on the saturation and brightness of the converted image (step S20).

The control unit 11 divides the area excluding the distance range obtained by multiplying the radius of the bright spot area 34 by a predetermined magnification into multiple areas (step S21). Specifically, as described above, the control unit 11 divides the area above the bright spot into an orange detection area 36 and the area below the bright spot into a green detection area 37. The control unit 11 determines whether a predetermined color component is present in each divided area at a ratio equal to or greater than a predetermined value (step S22). Specifically, the control unit 11 determines whether the orange detection area 36 contains orange dots and the green detection area 37 contains green dots at a ratio equal to or greater than a predetermined value.

The control unit 11 outputs the judgment result to the terminal 2 (step S23). The control unit 21 of the terminal 2 displays the judgment result output from the server 1 (step S24), and the series of processes ends.

Note that, although the above description has been given of terminal 2 cutting out hologram section 30 and server 1 determining authenticity, this embodiment is not limited to this. For example, terminal 2 may transmit the entire frame image to server 1, which may then cut out the image. Alternatively, terminal 2 may perform the authenticity determination on its own. In this way, the processing content executed by server 1 and terminal 2 can be appropriately divided and changed, and the present embodiment may also include a case where all processing is executed by a single computer.

In addition, while the above describes a judgment based on a single cut-out image, the present embodiment is not limited to this. Specifically, the server 1 acquires multiple cut-out images (e.g., five) from the terminal 2, and if it determines that orange and green color components are present in a ratio equal to or greater than a predetermined value in the majority of the images (or if it determines that the ratio of luminance values of each of the RGB colors is a predetermined ratio in the majority of the images), it determines that the object 3 to be judged for authenticity is genuine. In this way, by making a judgment using multiple images, it is expected that erroneous judgments can be prevented.

As described above, according to this embodiment 1, it is possible to effectively assist in authenticity determination.

(Embodiment 2)
In this embodiment, a two-stage determination will be described, that is, a determination made in a state where the zeroth-order diffracted light is irradiated onto the hologram section 30, and a determination made in a state where the zeroth-order diffracted light is not irradiated onto the hologram section 30. Note that the same reference numerals are used to denote contents that overlap with those in the first embodiment, and description thereof will be omitted.

Figure 14 is an explanatory diagram showing an overview of embodiment 2. The overview of this embodiment will be explained based on Figure 14.

First, the terminal 2 displays the first rectangular region 32 and the second rectangular region 33 superimposed on the frame image in the same manner as in the first embodiment, guides the bright spot region 34 to the second rectangular region 33 by the guide line 35, and cuts out an image in which the zeroth order diffracted light is irradiated at a predetermined position (center) of the hologram section 30. The server 1 then divides the image into an orange detection region 36 and a green detection region 37, and determines whether or not the orange and green color components are present in each region at a ratio equal to or greater than a predetermined value.

In this embodiment, the position of the bright spot is further guided to a position outside the hologram section 30 (upper side in FIG. 14) as shown on the right side of FIG. 14, and a frame image (second image) that is not irradiated with zero-order diffracted light is obtained. Then, by confirming that a predetermined color component (orange in this embodiment) is not present in the image (it is below a predetermined value), it becomes possible to detect a fake that is simply orange on the top and green on the bottom.

Specifically, terminal 2 first displays a superimposed guiding line 35 for guiding the position of the bright spot (the irradiation position of the zeroth-order diffracted light) to a predetermined position outside hologram section 30. For example, as shown on the right side of Fig. 14, terminal 2 draws a first rectangular area 32 in the same manner as in embodiment 1, and draws a third rectangular area 38 at a predetermined position outside hologram section 30. Terminal 2 then draws a guiding line 35 extending from the center of bright spot area 34 to third rectangular area 38. This guides the position of the bright spot to the outside of hologram section 30, and an image not irradiated with zeroth-order diffracted light is obtained.

The server 1 converts the image into an HSV image. The server 1 then determines whether the proportion of a predetermined color component is equal to or less than a predetermined value based on the hue, saturation, and brightness of the converted image. Specifically, the server 1 detects pixels of the orange color component by comparing the hue, saturation, and brightness of the HSV image with respective thresholds, and determines whether the number of detected pixels is equal to or less than a predetermined value. That is, the server 1 counts pixels whose hue is within a predetermined numerical range and whose saturation and brightness are equal to or greater than a predetermined threshold as orange dots, and determines whether the number of counted orange dots is equal to or less than a predetermined value. In this way, the server 1 confirms that the hologram section 30 is not reproduced in orange when the zero-order diffracted light is not irradiated.

The server 1 judges the authenticity of the object 3 to be subjected to authenticity judgment based on the judgment result when the zeroth-order diffracted light is irradiated to a predetermined position (center) on the hologram section 30 and the judgment result when the zeroth-order diffracted light is not irradiated to the hologram section 30. That is, the server 1 judges that the object 3 to be subjected to authenticity judgment is genuine when it judges that the orange and green color components are present in the orange detection area 36 and the green detection area 37, respectively, at a ratio equal to or greater than a predetermined value in the former and judges that the ratio of the orange color component is equal to or less than a predetermined value in the latter.

As in the first embodiment, the server 1 may make a judgment based on the luminance of each RGB color, rather than the color in the HSV color space. Specifically, when the bright spot area 34 overlaps the second rectangular area 33, the server 1 judges whether the ratio of the luminance values of each RGB color of each dot (pixel) in the orange detection area 36 and the green detection area 37 is a predetermined ratio, and when the bright spot area 34 overlaps the third rectangular area 38, the server 1 judges whether the ratio of the luminance values of each RGB color of each dot is a predetermined ratio. The server 1 may then judge authenticity based on the two judgment results.

15 is a flowchart showing the process steps executed by the authenticity determining system according to embodiment 2. After executing the process of step S18, the terminal 2 executes the following process.
The control unit 21 of the terminal 2 acquires a frame image of the hologram unit 30 (object) (step S201). The control unit 21 detects the position of the marker 31 from the frame image (step S202). The control unit 21 also detects the position of the bright spot (the irradiation position of the zero-order diffracted light) from the frame image (step S203).

Based on the position of the marker 31 detected in step S202 and the position of the bright spot detected in step S203, the control unit 21 superimposes and displays a guiding line 35 for guiding the position of the bright spot to a predetermined position outside the hologram unit 30 on the frame image (step S204). That is, the control unit 21 superimposes and displays a third rectangular area 38 located outside the hologram unit 30 according to the position of the marker 31, and superimposes and displays a guiding line 35 connecting the center of the third rectangular area 38 and the center of the bright spot area 34. By guiding the bright spot area 34 to the third rectangular area 38 outside the hologram unit 30, the control unit 21 acquires a frame image (second image) in which the 0th order diffracted light is not irradiated to the hologram unit 30.

The control unit 21 determines whether the position of the bright spot (the center of the bright spot area 34) overlaps with a predetermined position (third rectangular area 38) outside the hologram unit 30 (step S205). If it is determined that they do not overlap (S205: NO), the control unit 21 returns the process to step S201.

If it is determined that there is overlap (S205: YES), the control unit 21 cuts out an image area corresponding to the hologram unit 30 from the frame image (step S206). The control unit 21 transmits the cut-out image to the server 1 (step S207).

The control unit 11 of the server 1 converts the image acquired from the terminal 2 into an HSV image (step S208). The control unit 11 determines whether the proportion of a predetermined color component is equal to or less than a predetermined value based on the hue, saturation, and brightness of the converted image (step S209). Specifically, the control unit 11 determines whether the number of orange dots (number of pixels) is equal to or less than a certain number.

The control unit 11 judges the authenticity of the authenticity judgment target 3 based on the judgment result in step S22 and the judgment result in step S209 (step S210). That is, the control unit 11 judges the authenticity based on the judgment result of whether or not a predetermined color component exists at a rate equal to or greater than a predetermined value from an image in which the zeroth-order diffracted light is irradiated to a predetermined position (center) on the hologram unit 30, and the judgment result of whether or not the rate of the predetermined color component is equal to or less than a predetermined value from an image in which the zeroth-order diffracted light is not irradiated to the hologram unit 30. If the control unit 11 judges that the predetermined color component exists at a rate equal to or greater than a predetermined value in the former and that the rate of the predetermined color component is equal to or less than a predetermined value in the latter, it judges that the authenticity judgment target 3 is genuine.

The control unit 11 outputs the judgment result to the terminal 2 (step S211). The control unit 21 of the terminal 2 displays the judgment result (step S212), and the series of processes ends.

From the above, according to this embodiment 2, it is expected that the accuracy of authenticity determination can be improved by performing a two-stage determination: a state in which the zeroth order diffracted light is irradiated onto the hologram section 30, and a state in which the zeroth order diffracted light is not irradiated onto the hologram section 30.

(Variation 1)
In the first embodiment, a hologram in which orange and green wavelengths are diffracted (a Lippmann hologram in which multiple colors are diffracted) is taken as an example of the hologram to be authenticated, but the present embodiment is not limited to this. For example, a hologram in which a single color is diffracted may be used.

When a monochromatic hologram is used, the hologram cannot be seen even if the bright spot is aligned with the center of the hologram section 30, but a diffracted hologram can be seen if the bright spot is moved away from the center of the hologram section 30. Therefore, the terminal 2 displays a rectangular area at a specified position outside the hologram section 30 as the target position of the bright spot, and superimposes a guiding line 35 (object) connecting the rectangular area and the bright spot area 34, thereby guiding the position of the bright spot to the outside of the hologram section 30.

When the position of the bright spot overlaps with a predetermined position outside the hologram section 30, the terminal 2 cuts out the image area corresponding to the hologram section 30 and transmits it to the server 1. The server 1 determines whether or not a predetermined color component is present in the image area acquired from the terminal 2 at a ratio equal to or greater than a predetermined value, thereby determining the authenticity. Alternatively, the server 1 determines whether or not the ratio of the brightness values of each of the RGB colors of each dot (pixel) in the acquired image area is a predetermined ratio, thereby determining the authenticity.

In this way, a monochrome hologram may be used as the hologram.

(Variation 2)
Not only a single-color hologram, but also a hologram that appears to diffract into two or more colors (multiple colors) may be used. In this case, as in the above, the terminal 2 displays a guiding line 35 for guiding the position of the luminance to a predetermined position superimposed on the captured image. When the position of the bright point overlaps with the predetermined position, the server 1 judges whether each color component is present in the image area corresponding to the hologram section 30 at a ratio equal to or greater than a predetermined value (or judges whether the ratio of the luminance values of each color of RGB is a predetermined ratio) to judge authenticity.

(Variation 3)
A diffraction grating is also an optical structure capable of guiding a bright spot to determine authenticity. In this case, as in the first embodiment, the terminal 2 superimposes a guiding line 35 on the captured image for guiding the position of the bright spot (specularly reflected light) to a predetermined position on the diffraction grating, and guides the bright spot to a position on the diffraction grating. The server 1 can determine whether a predetermined diffracted light exists in a periodic range according to the direction and pitch of the diffraction grating, with the zeroth-order diffracted light as the center (whether a predetermined color component exists at a predetermined ratio, or whether dots (pixels) with a luminance value equal to or greater than a predetermined value exist periodically), thereby determining whether the diffraction grating is genuine or not.

The embodiments disclosed herein are illustrative in all respects and should not be considered limiting. The scope of the present invention is indicated by the claims, not by the above meaning, and is intended to include all modifications within the meaning and scope of the claims.

The matters described in each embodiment can be combined with each other. In addition, the independent claims and dependent claims described in the claims can be combined with each other in any and all combinations regardless of the citation format. Furthermore, the claims use a format in which a claim cites two or more other claims (multi-claim format), but this is not limited to this. They may also be written using a format in which a multiple claim cites at least one other multiple claim (multi-multi-claim).

REFERENCE SIGNS LIST 1 Server 11 Control unit 12 Main memory unit 13 Communication unit 14 Auxiliary memory unit P1 Program 2 Terminal 21 Control unit 22 Main memory unit 23 Communication unit 24 Display unit 25 Input unit 26 Imaging unit 27 Light source 28 Auxiliary memory unit P2 Program 3 Object to be authenticated 30 Hologram unit 31 Marker 32 First rectangular area 33 Second rectangular area 34 Bright spot area 35 Guiding line 36 Orange detection area 37 Green detection area 38 Third rectangular area

Claims (15)

Acquire an image of the object illuminated with light;
Detecting the position of the object from the image;
Detecting an irradiation position of the zeroth order diffracted light from the image;
A program that causes a computer to execute a process of superimposing an object for guiding the irradiation position of the zeroth-order diffracted light to a predetermined position on the object, on the image, in accordance with the detected position of the object and the irradiation position of the zeroth-order diffracted light. The program according to claim 1 , further comprising: cutting out an image area corresponding to the object from the image when the irradiation position of the zeroth-order diffracted light overlaps with the predetermined position. Dividing the cut-out image area into a plurality of areas based on the center of gravity of the irradiation range of the zeroth-order diffracted light;
The program according to claim 2 , further comprising: determining whether or not a predetermined color component is present in each divided area at a rate equal to or greater than a predetermined value. Detecting pixels of a predetermined color component from the divided regions;
The program according to claim 3 , further comprising: determining whether or not the detected number of pixels is equal to or greater than a predetermined value. Detecting pixels of a predetermined color component from the divided regions;
The program according to claim 3 , further comprising: determining whether or not a value obtained by dividing the number of detected pixels by an area of the divided region is equal to or greater than a predetermined value. Dividing the cut-out image area into a plurality of areas based on the center of gravity of the irradiation range of the zeroth-order diffracted light;
The program according to claim 2 , further comprising: determining whether or not a ratio of luminance values of each of RGB colors of each pixel in each divided region is a predetermined ratio. The program according to claim 1 , further comprising: detecting a marker attached to the object from the image, thereby detecting the position of the object. Based on the detected position of the marker, a first rectangular area surrounding the object and a second rectangular area to be irradiated with the zero-order diffracted light are specified;
The program according to claim 7 , further comprising: displaying objects respectively representing the first rectangular area and the second rectangular area superimposed on the image. Identifying an image area from the image that corresponds to an irradiation range of the zeroth order diffracted light;
The program according to claim 1 , further comprising: displaying an object representing the identified image region superimposed on the image. The program according to claim 1 , further comprising: displaying, when the irradiation position of the zeroth-order diffracted light overlaps with the predetermined position, an object for guiding the irradiation position of the zeroth-order diffracted light to a position outside the object, superimposed on the image. When the irradiation position of the zeroth-order diffracted light overlaps with the outer position, an image area corresponding to the object is cut out from the image;
The program according to claim 10 , further comprising: determining whether a ratio of a predetermined color component in the cut-out image region is equal to or less than a predetermined value or equal to or more than a predetermined value. When the irradiation position of the zeroth order diffracted light overlaps with the outer position, an image area corresponding to the object is cut out from the image;
The program according to claim 10, further comprising: determining whether or not a ratio of luminance values of each of RGB colors of each pixel in the cut-out image region is a predetermined ratio. Acquire an image of the object illuminated with light;
Detecting the position of the object from the image;
Detecting an irradiation position of the zeroth order diffracted light from the image;
an object for guiding the irradiation position of the zeroth order diffracted light to a predetermined position on the object, superimposed on the image, in accordance with the detected position of the object and the irradiation position of the zeroth order diffracted light. An information processing device including a control unit,
The control unit:
Acquire an image of the object illuminated with light;
Detecting the position of the object from the image;
Detecting an irradiation position of the zeroth order diffracted light from the image;
an object for guiding an irradiation position of the zeroth-order diffracted light to a predetermined position on the object in accordance with the detected position of the object and the irradiation position of the zeroth-order diffracted light, superimposed on the image and displayed. Acquire an image of the object illuminated with light;
Detecting the position of the object from the image;
Detecting an irradiation position of the zeroth order diffracted light from the image;
A program that causes a computer to execute a process of superimposing and displaying an object that connects the irradiation position of the zeroth order diffracted light and the predetermined position, the object being used to guide the irradiation position of the zeroth order diffracted light to a predetermined position according to the detected position of the object and the irradiation position of the zeroth order diffracted light, on the image.

Images