Authentication device, authentication method, and program

Abstract

This reduces the possibility of mistakenly identifying someone as the intended person. [Solution] The authentication device comprises a first authentication processing unit and a second authentication processing unit. The first authentication processing unit performs a first authentication process on a person using a first visible light image, which is an image of the person to be authenticated taken in visible light. If the first authentication process is successful, the second authentication processing unit performs a second authentication process on a person using an ultraviolet image, which is an image of the person taken in ultraviolet light.

Description

Technical Field

[0001] The present invention relates to an authentication device, an authentication method, and a program.

Background Art

[0002] In recent years, authentication devices using images have been increasingly popular. For example, Patent Document 1 describes a device that performs the following processes. First, the device acquires an image of a predetermined part of a person, and compares this image with an image of the predetermined part of a person registered in advance. Then, when this comparison fails, the device compares a partial image of the photographed predetermined part with a partial image of the predetermined part of the person registered in advance.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When performing human authentication, it is necessary to reduce the possibility of misidentifying another person as the person to be authenticated.

Means for Solving the Problems

[0005] An authentication device according to one aspect of the present disclosure includes: first authentication processing means for performing a first authentication process of the person using a first visible light image that is an image of the person photographed with visible light; second authentication processing means for performing a second authentication process of the person using an ultraviolet image that is an image of the person photographed with ultraviolet light when the first authentication process is successful; and.

[0006] An authentication method according to one aspect of the present disclosure is such that a computer Using a first visible light image, which is an image of the person to be authenticated taken in visible light, the first authentication process for the person is performed. If the first authentication process is successful, a second authentication process for the person is performed using the ultraviolet image, which is an image of the person taken with ultraviolet light.

[0007] One aspect of this disclosure is a program for a computer, A first authentication processing means that performs a first authentication process on a person using a first visible light image, which is an image of the person to be authenticated taken in visible light, If the first authentication process is successful, a second authentication processing means performs a second authentication process on the person using an ultraviolet image, which is an image of the person taken with ultraviolet light. To make it happen. [Effects of the Invention]

[0008] According to one example of this disclosure, the possibility of misidentifying someone as the person who should be authenticated is reduced. [Brief explanation of the drawing]

[0009] [Figure 1] This figure shows an example of the functional configuration of the authentication device related to this disclosure. [Figure 2] This flowchart shows an example of how the authentication device works. [Figure 3] This figure shows an example of a device used in conjunction with an authentication device. [Figure 4] This figure shows an example of the functional configuration of an authentication device. [Figure 5] This figure shows an example of the information stored in the memory unit. [Figure 6] This is a flowchart showing an example of the master image generation process. [Figure 7] This flowchart shows an example of how the authentication device works. [Figure 8] This figure shows an example of the hardware configuration of an authentication device. [Modes for carrying out the invention]

[0010] Hereinafter, in the present disclosure, the drawings are associated with one or more embodiments. Also, in all the drawings, the same reference numerals are assigned to the same components, and the description thereof will be omitted as appropriate. Further, in the following description, the "image" used for authentication may be the image itself or the feature amount of the image.

[0011] As shown in FIG. 1, the authentication device 10 includes a first authentication processing unit 110 and a second authentication processing unit 120.

[0012] The first authentication processing unit 110 performs the first authentication process of a person using a first visible light image which is an image obtained by photographing the person to be authenticated with visible light. The first visible light image is, for example, a face image and includes information on the surface of the person's body.

[0013] When the first authentication process is successful, the second authentication processing unit 120 performs the second authentication process of the person using an ultraviolet image which is an image obtained by photographing the person to be authenticated with ultraviolet light. The ultraviolet image is, for example, a face image and includes information on the person's body, specifically, information on a part slightly deeper than the surface, such as information on the inside of the skin. An example of this information is information indicating the position and shape of wounds the person has suffered in the past and the distribution of pigments (e.g., melanin) in the person's skin.

[0014] The authentication device 10 operates as shown in, for example, the flowchart of FIG. 2.

[0015] First, the first authentication processing unit 110 of the authentication device 10 acquires a first visible light image (step S10), and performs a first authentication process using this first visible light image (step S20). In this first authentication process, the first authentication processing unit 110 uses, for example, a first master visible light image of the person to be authenticated. The first master visible light image is, for example, a face image of the person to be authenticated. Also, when there are a plurality of persons to be authenticated, a first master visible light image is prepared for each of these plurality of persons. Then, when there exists a first master visible light image among the plurality of first master visible light images whose similarity to the first visible light image is equal to or greater than a reference value, the first authentication processing unit 110 determines that the first authentication process has succeeded (step S30: Yes). When there are a plurality of first master visible light images whose similarity is equal to or greater than the reference value, the first authentication processing unit 110 selects the first visible light image with the highest similarity.

[0016] When the first authentication process is successful (step S30: Yes), the second authentication processing unit 120 of the authentication device 10 acquires an ultraviolet image, and performs a second authentication process using this ultraviolet image (step S40). In this second authentication process, the first authentication processing unit 110 uses, for example, a master ultraviolet image of the same person as the first master visible light image identified in step S30. This master ultraviolet image is also prepared in advance. Then, when the similarity of the master ultraviolet image to the ultraviolet image is equal to or greater than a reference value, the second authentication processing unit 120 determines that the second authentication process has succeeded (step S50: Yes).

[0017] Thereafter, a predetermined process is executed (step S60). This predetermined process is, for example, to allow the person shown in the first visible light image and the ultraviolet image to pass through a gate or a door, but is not limited thereto.

[0018] Thus, if the authentication device 10 successfully authenticates using a visible light image, it then performs authentication using an ultraviolet image. The information obtained from the ultraviolet image is different from the information obtained from the visible light image. Therefore, because authentication is performed twice using different information, the possibility of misidentifying someone as the person to be authenticated is reduced. Furthermore, even if someone tries to impersonate the person to be authenticated using a mask or photograph, the authentication device 10 performs authentication using an ultraviolet image, thus reducing the possibility of misidentifying that person as the person to be authenticated.

[0019] The following describes a detailed example of the authentication device 10.

[0020] The authentication device 10 is used in conjunction with and controls the visible light imaging device 20, the visible light source 22, the ultraviolet imaging device 30, and the ultraviolet source 32, as shown in Figure 3, for example.

[0021] The visible light imaging device 20 and the visible light source 22 are used to generate a first visible light image and a second visible light image, which will be described later. The visible light imaging device 20 photographs, for example, a person located in a target area. The visible light source 22 illuminates the person located in this target area with visible light when the visible light imaging device 20 generates an image. An example of a target area is, for example, in front of an entrance gate or door, or in front of an area where people are desired to enter, but is not limited to these.

[0022] The ultraviolet imaging device 30 and the ultraviolet light source 32 are used when generating ultraviolet images. The ultraviolet imaging device 30 photographs a person located in the same target area as, for example, the visible light imaging device 20. Therefore, the visible light imaging device 20 and the ultraviolet imaging device 30 can photograph the same person simultaneously. Note that "simultaneously" here includes cases where the generation times of each image do not strictly coincide. For example, "simultaneously" means that the difference in shooting timing is 0.5 seconds or less. The same applies to the description below. The ultraviolet light source 32 irradiates ultraviolet light onto the person located in the target area when the ultraviolet imaging device 30 generates an image.

[0023] The ultraviolet source 32 may have a variable wavelength of ultraviolet light emitted. For example, the ultraviolet source 32 may have multiple LEDs that emit ultraviolet light of different wavelengths, and by selecting which of these LEDs to emit light, the wavelength of the ultraviolet light emitted may be made variable.

[0024] As shown in Figure 4, the authentication device 10 has, in addition to the first authentication processing unit 110 and the second authentication processing unit 120 shown in Figure 1, an image capture control unit 130 and an entry processing unit 140, and can also utilize information stored in the storage unit 150. The storage unit 150 may be part of the authentication device 10 or it may be a separate device from the authentication device 10.

[0025] The imaging control unit 130 controls the visible light imaging device 20, the visible light source 22, the ultraviolet imaging device 30, and the ultraviolet source 32. A detailed example of the processing performed by the imaging control unit 130 will be described later using a flowchart.

[0026] The entry processing unit 140 performs the process necessary for the authenticated person to enter a specific area when the second authentication processing unit 120 has successfully completed the second authentication process. The specific area is, for example, a partitioned area such as a facility or room that the authenticated person wishes to enter. Hereinafter, this process will be referred to as the entry process. An example of the entry process is, but is not limited to, opening an entrance gate or opening a room door.

[0027] The storage unit 150 stores various types of information used in the authentication process performed by the authentication device 10. For example, as shown in Figure 5, the storage unit 150 stores, for each of several people, a first master visible light image, a master ultraviolet image, a second master visible light image, and information that identifies the wavelength of ultraviolet light used when generating the master ultraviolet image. The information that identifies the wavelength of ultraviolet light may be, for example, the wavelength itself, or it may be information indicating the type of LED.

[0028] As explained using Figure 2, the first master visible light image is used to authenticate the first visible light image, and the master ultraviolet image is used to authenticate the ultraviolet image. The second master visible light image is an image of the person taken in visible light when the master ultraviolet image was generated, and is used to align the master ultraviolet image with the ultraviolet image. The second master visible light image is generated, for example, at the same time as the master ultraviolet image. Details of the processing using the second master visible light image will be described later.

[0029] Furthermore, the first master visible light image may also serve as the second master visible light image. That is, the first master visible light image may be used to align the master ultraviolet image with the ultraviolet image. In this case, the master ultraviolet image is generated simultaneously with the first master visible light image. For example, the master ultraviolet image is generated at the same time as the first master visible light image.

[0030] The first master visible light image, the master ultraviolet image, and the second master visible light image are generated in advance and stored in the storage unit 150. Figure 6 shows an example of the image generation process. This process may be performed using the authentication device 10, the visible light imaging device 20, the visible light source 22, the ultraviolet imaging device 30, and the ultraviolet source 32, or it may be performed using other devices. In the following description, it will be assumed that these processes are performed using the authentication device 10, the visible light imaging device 20, the visible light source 22, the ultraviolet imaging device 30, and the ultraviolet source 32.

[0031] First, the imaging control unit 130 of the authentication device 10 controls the visible light imaging device 20 and the visible light source 22 to cause the visible light imaging device 20 to generate a first master visible light image (step S110), and stores this first master visible light image in the storage unit 150 (step S120). The imaging control unit 130 also controls the visible light imaging device 20 and the visible light source 22, as well as the ultraviolet imaging device 30 and the ultraviolet source 32 to cause the visible light imaging device 20 to generate a second master visible light image and the ultraviolet imaging device 30 to generate a master ultraviolet image (step S130), and stores the second master visible light image and the master ultraviolet image in the storage unit 150 (step S140).

[0032] If the wavelength of ultraviolet light emitted by the ultraviolet light source 32 is variable, in step S130, the imaging control unit 130 determines the wavelength of ultraviolet light emitted by the ultraviolet light source 32 and irradiates the ultraviolet light source 32 with ultraviolet light of this wavelength. Here, the imaging control unit 130 determines the wavelength randomly. Then, in step S140, the imaging control unit 130 stores information that allows for the identification of this wavelength in the storage unit 150.

[0033] If the first master visible light image also serves as the second master visible light image, then in step S110, the first master visible image and the master ultraviolet image are generated, and in step S120, the first master visible image and the master ultraviolet image are stored in the storage unit 150. Steps S130 and S140 are then omitted.

[0034] The authentication device 10 then performs the authentication process according to the flowchart shown in Figure 7, for example.

[0035] When a person wishing to be authenticated enters the target area, the imaging control unit 130 of the authentication device 10 controls the visible light imaging device 20 and the visible light source 22 to cause the visible light imaging device 20 to generate a first visible light image (step S12). Next, the authentication processing unit 110 acquires this first visible light image and executes the first authentication process (step S20). At this time, the authentication device 10 uses the first master visible light image stored in the storage unit 150. A detailed example of the first authentication process using the first visible light image and the first master visible light image is explained with reference to Figure 2.

[0036] If the first authentication process is successful (step S30: Yes), the imaging control unit 130 controls the ultraviolet imaging device 30 and the ultraviolet light source 32 to cause the ultraviolet imaging device 30 to generate an ultraviolet image, and controls the visible light imaging device 20 and the visible light source 22 to cause the visible light imaging device 20 to generate a second master visible light image (step S32).

[0037] If the memory unit 150 stores information that can identify the wavelength of ultraviolet light, the imaging control unit 130 reads this information in step S32 and irradiates the ultraviolet light source 32 with ultraviolet light of the wavelength indicated by the read information. In other words, if the wavelength of ultraviolet light to be irradiated onto a person when generating an ultraviolet image is determined for each person, and this wavelength is the same as the wavelength used when the master ultraviolet image was generated, the imaging control unit 130 controls the ultraviolet light source 32 when generating the ultraviolet image to irradiate the person with ultraviolet light of that wavelength.

[0038] The second authentication processing unit 120 then performs the second authentication process using the second visible light image and the ultraviolet image.

[0039] In detail, the second authentication processing unit 120 uses the second master visible light image and the second visible light image to align the master ultraviolet image with the ultraviolet image (step S34). For example, the second authentication processing unit 120 detects predetermined parts of the human body from the second master visible light image and the second visible light image. These parts are, for example, at least one, preferably more, of the eyes, nose, and mouth. The difference between the position of that part in the second master visible light image and the position of that part in the second visible light image is defined as the amount of shift of the ultraviolet image relative to the master ultraviolet image. The second authentication processing unit 120 then determines which part of the master ultraviolet image corresponds to which part of the ultraviolet image so as to minimize this amount of shift.

[0040] The second authentication processing unit 120 then performs a second authentication process using the master ultraviolet image and the ultraviolet image after the misalignment has been corrected (step S40). If the second authentication process is successful (step S50: Yes), the entry processing unit 140 performs the entry process (step S60).

[0041] In the flowchart shown in Figure 7, the imaging control unit 130 may generate an ultraviolet image simultaneously with the first visible light image. In this case, the first visible light image also serves as the second visible light image. Furthermore, in step S12, both the first visible light image and the ultraviolet image are generated, and step S32 is omitted.

[0042] As an example of hardware configuration, the authentication device 10 includes a bus 1010, a processor 1020, a memory 1030, a storage device 1040, an input / output interface 1050, and a network interface 1060, as shown in Figure 8.

[0043] Bus 1010 is a data transmission path for the processor 1020, memory 1030, storage device 1040, input / output interface 1050, and network interface 1060 to send and receive data to and from each other. However, the method of connecting the processor 1020 and the other components to each other is not limited to bus connection.

[0044] The 1020 processor is a processor implemented in components such as the CPU (Central Processing Unit) and GPU (Graphics Processing Unit).

[0045] Memory 1030 is a main memory device implemented using RAM (Random Access Memory), etc.

[0046] The storage device 1040 is an auxiliary storage device implemented as a removable media such as an HDD (Hard Disk Drive), SSD (Solid State Drive), or memory card, or as a FROM (Flash Read Only Memory), and has a recording medium. The recording medium of the storage device 1040 stores program modules that implement each function of the authentication device 10 (for example, the first authentication processing unit 110, the second authentication processing unit 120, the image capture control unit 130, and the entry processing unit 140). The processor 1020 reads each of these program modules into the memory 1030 and executes them, thereby realizing each function corresponding to the program module. The storage device 1040 may also function as a storage unit 150.

[0047] The input / output interface 1050 is an interface for connecting the authentication device 10 with various input / output devices. For example, the authentication device 10 may communicate with the storage unit 150 via the input / output interface 1050.

[0048] The network interface 1060 is an interface for connecting the authentication device 10 to a network. This network may be, for example, a LAN (Local Area Network) or a WAN (Wide Area Network). The method by which the network interface 1060 connects to the network may be wireless or wired. The authentication device 10 may communicate with the storage unit 150, the visible light imaging device 20, the visible light source 22, the ultraviolet imaging device 30, and the ultraviolet source 32 via the network interface 1060.

[0049] In summary, using the authentication device 10 reduces the possibility of mistakenly identifying someone as the person who should be authenticated.

[0050] Furthermore, even if the ultraviolet imaging device 30 photographs the same person, the information contained in the ultraviolet image may differ if the wavelength of ultraviolet light changes. If the ultraviolet source 32 can selectively emit ultraviolet light of multiple wavelengths and can change the wavelength used to generate the master ultraviolet image depending on the person, the authentication device 10 can match the wavelength of ultraviolet light emitted by the ultraviolet source 32 when generating the ultraviolet image to the wavelength used when the master ultraviolet image was generated. Therefore, the possibility of misidentifying another person as the person to be authenticated becomes even smaller.

[0051] Furthermore, the second authentication processing unit 120 of the authentication device 10 aligns the ultraviolet image with the master ultraviolet image using the second master visible light image and the second visible light image, and then performs the second authentication process using the aligned ultraviolet image and the master ultraviolet image. As a result, the possibility of incorrectly determining that the person to be authenticated is not the person in question is reduced.

[0052] Although the present disclosure has been described above with reference to embodiments, the present disclosure is not limited to the embodiments described above. Various modifications to the structure and details of the present disclosure can be made as can be understood by those skilled in the art within the scope of the present disclosure. Furthermore, each embodiment can be combined with other embodiments as appropriate.

[0053] Furthermore, while the flowcharts used in the above description show multiple steps (processes) in sequence, the execution order of the steps performed in each embodiment is not limited to the order in which they are described. In each embodiment, the order of the illustrated steps can be changed to the extent that it does not impair the content.

[0054] Some or all of the above embodiments may also be described as follows, but are not limited to the following: 1. A first authentication processing means that performs a first authentication process on a person using a first visible light image, which is an image of the person to be authenticated taken in visible light. If the first authentication process is successful, a second authentication processing means performs a second authentication process on the person using an ultraviolet image, which is an image of the person taken with ultraviolet light. An authentication device equipped with the following features. 2. In the authentication device described in item 1 above, An authentication device comprising, upon success in the first authentication process, a shooting control means for causing a UV imaging device that generates the UV image to generate the UV image. 3. In the authentication device described in item 2 above, The second authentication processing means performs the second authentication process using the person's master ultraviolet image and the ultraviolet image, For each of the multiple persons, the wavelength of ultraviolet light to be irradiated to that person when generating the ultraviolet image is determined. The wavelength specified for each person is the wavelength used when the master ultraviolet image was generated. The aforementioned shooting control means controls an ultraviolet source that irradiates the person with ultraviolet light when the ultraviolet image is generated, and irradiates the person with ultraviolet light of a wavelength that should be irradiated to that person, as an authentication device. 4. In the authentication device described in item 1 above, The ultraviolet imaging device that generates the ultraviolet image is equipped with an imaging control means for generating the ultraviolet image, The aforementioned shooting control means further causes a visible light shooting device, which performs shooting in visible light, to generate a second visible light image, which is an image of the person taken in visible light, when the ultraviolet image is generated. The second authentication processing means is an authentication device that further performs the second authentication processing using the second visible light image. 5. In the authentication device described in item 4 above, The second authentication processing means is: The ultraviolet image, the second visible light image, the master ultraviolet image of the person, and the master visible light image, which is an image of the person taken in visible light when the master ultraviolet image was generated, are acquired. An authentication device that uses the second visible light image and the master visible light image to align the person included in the master ultraviolet image with the person included in the ultraviolet image, and then performs the second authentication process. 6. In the authentication device described in item 4 or 5 above, The ultraviolet imaging device and the visible light imaging device are installed in front of a specific area. An authentication device comprising an entry processing means that performs processing for the person to enter the area if the second authentication process is successful. 7. The computer, Using a first visible light image, which is an image of the person to be authenticated taken in visible light, the first authentication process for the person is performed. An authentication method that, if the first authentication process is successful, performs a second authentication process on the person using an ultraviolet image, which is an image of the person taken with ultraviolet light. 8. On the computer, A first authentication processing means that performs a first authentication process on a person using a first visible light image, which is an image of the person to be authenticated taken in visible light, If the first authentication process is successful, a second authentication processing means performs a second authentication process on the person using an ultraviolet image, which is an image of the person taken with ultraviolet light. A program that makes this possible. 9. A recording medium on which the program described in item 8 above is recorded.

[0055] Furthermore, some or all of the configurations described in Appendices 2 to 6, which are subordinate to Appendice 1 above, may also be subordinate to each of Appendices 7 to 9 in the same way as Appendices 2 to 6. Moreover, not limited to Appendice 1 and Appendices 7 to 9, some or all of the configurations described as appendices may also be subordinate to various hardware, software, various recording means for recording software, or systems, without departing from the embodiments described above. [Explanation of Symbols]

[0056] 10 Authentication device 20 Visible light imaging device 22 Visible light source 30. Ultraviolet imaging device 32 UV source 110 First Authentication Processing Unit 120 Second Authentication Processing Unit 130 Imaging Control Unit 140 Entrance Processing Unit

Claims

1. A first authentication processing means that performs a first authentication process on a person using a first visible light image, which is an image of the person to be authenticated taken in visible light, If the first authentication process is successful, a second authentication processing means performs a second authentication process on the person using an ultraviolet image, which is an image of the person taken with ultraviolet light. An authentication device equipped with the following features.

2. In the authentication device according to claim 1, An authentication device comprising, upon successful completion of the first authentication process, a shooting control means for causing a UV imaging device that generates the UV image to generate the UV image.

3. In the authentication device according to claim 2, The second authentication processing means performs the second authentication process using the person's master ultraviolet image and the ultraviolet image. For each of the multiple persons, the wavelength of ultraviolet light to be irradiated to that person when generating the ultraviolet image is determined. The wavelength specified for each person is the wavelength used when the master ultraviolet image was generated. The aforementioned shooting control means controls an ultraviolet source that irradiates the person with ultraviolet light when the ultraviolet image is generated, and irradiates the person with ultraviolet light of a wavelength that should be irradiated to that person, as an authentication device.

4. In the authentication device according to claim 1, The ultraviolet imaging device that generates the ultraviolet image is equipped with an imaging control means for generating the ultraviolet image, The aforementioned shooting control means further causes a visible light shooting device, which performs shooting with visible light, to generate a second visible light image, which is an image of the person taken with visible light, when the ultraviolet image is generated. The second authentication processing means is an authentication device that further performs the second authentication processing using the second visible light image.

5. In the authentication device according to claim 4, The second authentication processing means is The ultraviolet image, the second visible light image, the master ultraviolet image of the person, and the master visible light image, which is an image of the person taken in visible light when the master ultraviolet image was generated, are acquired. An authentication device that uses the second visible light image and the master visible light image to align the person included in the master ultraviolet image with the person included in the ultraviolet image, and then performs the second authentication process.

6. In the authentication device according to claim 4 or 5, The ultraviolet imaging device and the visible light imaging device are installed in front of a specific area. An authentication device comprising an entry processing means that performs processing for the person to enter the area if the second authentication process is successful.

7. Computers Using a first visible light image, which is an image of the person to be authenticated taken in visible light, the first authentication process for the person is performed. An authentication method in which, if the first authentication process is successful, a second authentication process is performed on the person using an ultraviolet image, which is an image of the person taken with ultraviolet light.

8. On the computer, A first authentication processing means that performs a first authentication process on a person using a first visible light image, which is an image of the person to be authenticated taken in visible light, If the first authentication process is successful, a second authentication processing means performs a second authentication process on the person using an ultraviolet image, which is an image of the person taken with ultraviolet light. A program that makes this possible.

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