Information processing device, information processing method, and program

Abstract

An information processing device of the present disclosure comprises an imaging unit that images a subject and generates a captured image, a driving unit that changes an imaging angle of the imaging unit, and an estimating unit that estimates height information of a predetermined portion of the subject on the basis of the captured image and the imaging angle.

Description

[Technical Field]

[0001] This disclosure relates to an information processing device, an information processing method, and program Regarding. [Background technology]

[0002] Patent Document 1 describes an authentication system that authenticates a target person using a face image generated by capturing an image of the target person's face. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2015-136938 Summary of the Invention [Problem to be solved by the invention]

[0004] In the authentication system described in Patent Document 1, the camera is fixed, so there is a possibility that the accuracy of biometric authentication may decrease depending on the height of the person to be authenticated.

[0005] This disclosure relates to an information processing device, an information processing method, and program The purpose is to provide the following. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, there is provided a method for detecting a height of a predetermined part of the object based on the captured image and the image capturing angle, the method comprising: an acquisition unit that acquires a distance from the target to the imaging unit; a storage unit that stores a registered biometric image of a registered person and registered height information; and an authentication unit that executes a first biometric authentication using the registered biometric image and the biometric image of the target included in the captured image, and a second biometric authentication using the registered height information and the height information; Equipped with the estimation unit estimates the height information based on the distance, the imaging angle, and the position of the predetermined part in the captured image; the drive unit changes the imaging angle depending on the distance; and the imaging unit, when the distance is equal to or greater than a predetermined threshold, captures an image at a first imaging angle in which the center of the captured image is set to the face of the subject, and when the distance is less than the threshold, captures an image at a second imaging angle in which the center of the captured image is set to the top of the head of the subject. An information processing device is provided.

[0007] According to another aspect of this disclosure, The computer capturing an image of an object using an imaging device to generate a captured image; The computerchanging an imaging angle of the imaging device; The computer estimating height information of a predetermined part of the object based on the captured image and the imaging angle; a step of the computer acquiring a distance from the target to the imaging device; a step of the computer storing a registered biometric image of the enrolled person and registered height information; and a step of the computer executing a first biometric authentication using the registered biometric image and the biometric image of the target included in the captured image, and a second biometric authentication using the registered height information and the height information; Equipped with In the estimating step, the height information is estimated based on the distance, the imaging angle, and the position of the predetermined part in the captured image; in the changing step, the imaging angle is changed depending on the distance; and in the generating step, if the distance is equal to or greater than a predetermined threshold, imaging is performed at a first imaging angle in which the center of the captured image is set to the face of the subject, and if the distance is less than the threshold, imaging is performed at a second imaging angle in which the center of the captured image is set to the top of the head of the subject. A method for processing information is provided.

[0008] According to another aspect of the present disclosure, there are provided a method for detecting a height of a predetermined part of the object by using an imaging device to capture an image of the object and generate a captured image; changing an imaging angle of the imaging device; and estimating height information of a predetermined part of the object based on the captured image and the imaging angle. acquiring a distance from the target to the imaging device; storing a registered biometric image of the enrolled person and registered height information; and performing a first biometric authentication using the registered biometric image and the biometric image of the target included in the captured image, and a second biometric authentication using the registered height information and the height information. Run In the estimating step, the height information is estimated based on the distance, the imaging angle, and the position of the predetermined part in the captured image; in the changing step, the imaging angle is changed depending on the distance; and in the generating step, if the distance is equal to or greater than a predetermined threshold, imaging is performed at a first imaging angle in which the center of the captured image is set to the face of the subject, and if the distance is less than the threshold, imaging is performed at a second imaging angle in which the center of the captured image is set to the top of the head of the subject. Programs are offered. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a block diagram showing an example of the overall configuration of an authentication system according to a first embodiment. [Figure 2] 2 is a block diagram showing an example of a hardware configuration of the authentication device according to the first embodiment. FIG. [Figure 3] 1 is a front view showing the appearance of an authentication device according to a first embodiment. [Figure 4] 1 is a perspective view illustrating the internal structure of an authentication device according to a first embodiment. [Figure 5] 3 is a flowchart showing an outline of processing executed in the authentication system according to the first embodiment. [Figure 6] 3A and 3B are schematic diagrams illustrating the imaging angle and imaging range of a camera in the authentication device according to the first embodiment. [Figure 7] FIG. 2 is a diagram showing an example of a captured image according to the first embodiment. [Figure 8] 3A and 3B are schematic diagrams illustrating the imaging angle and imaging range of a camera in the authentication device according to the first embodiment. [Figure 9] FIG. 2 is a diagram showing an example of a captured image according to the first embodiment. [Figure 10] 3A and 3B are schematic diagrams illustrating the imaging angle and imaging range of a camera in the authentication device according to the first embodiment. [Figure 11] FIG. 2 is a diagram showing an example of a captured image according to the first embodiment. [Figure 12] FIG. 10 is a block diagram showing an example of a hardware configuration of an authentication device according to a second embodiment. [Figure 13] 10A and 10B are schematic diagrams illustrating an imaging angle and an imaging range of an authentication device according to a second embodiment. [Figure 14] 10A and 10B are schematic diagrams illustrating an imaging angle and an imaging range of an authentication device according to a second embodiment. [Figure 15] 10 is a flowchart showing an outline of processing executed in an authentication system according to a second embodiment. [Figure 16] FIG. 11 is a block diagram showing an example of a hardware configuration of an authentication device according to a third embodiment. [Figure 17] 10A and 10B are schematic diagrams illustrating an imaging angle and an imaging range of an authentication device according to a third embodiment. [Figure 18] 10A and 10B are schematic diagrams illustrating an imaging angle and an imaging range of an authentication device according to a third embodiment. [Figure 19] 10 is a flowchart showing an outline of processing executed in an authentication system according to a fourth embodiment. [Figure 20] 10 is a flowchart showing an outline of processing executed in an authentication system according to a fifth embodiment. [Figure 21] 13 is a flowchart showing an outline of processing executed in an authentication system according to a sixth embodiment. [Figure 22] FIG. 13 is a functional block diagram showing the overall configuration of an information processing device according to a seventh embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. In the drawings, similar or corresponding elements are designated by the same reference numerals, and descriptions thereof may be omitted or simplified. [First embodiment]

[0011] First, a description will be given of the configuration of an authentication system 1 according to the first embodiment. Fig. 1 is a block diagram showing an example of the overall configuration of an authentication system 1 according to the first embodiment.

[0012] The authentication system 1 acquires biometric information of a person to be authenticated (hereinafter also referred to as the person to be authenticated) and performs biometric authentication by comparing the biometric information with pre-registered biometric information. In addition to biometric authentication, the authentication system 1 also authenticates the person based on height information of the person estimated from a captured image. The authentication system 1 performs two-factor authentication. Note that the term "subject" includes not only people, but also animals such as dogs and snakes, plants, robots, etc. In the case of non-living objects such as robots, for example, the term "biometric information" can be read as "appearance information."

[0013] In this specification, height information primarily refers to, but is not limited to, the height of a person. The term "height information" is used to mean, for example, the height from the ground to the position of a specific part of a person (eyes, nose, ears, mouth, etc.), but is not limited to this. Height information includes not only the length from the ground but also the length from the subject's feet to the specific part (eyes, nose, ears, mouth, etc.). The specific part to be the target of height information estimation is preferably the eyes, nose, ears, mouth, chin, etc. This has the advantage that the position of the specific part can be easily calculated from the face image.

[0014] The authentication system 1 can be applied to, for example, identity verification for immigration at airports, identity verification at government agencies, identity verification for entry and exit at factories and offices, identity verification for entry and exit at event venues, and the like.

[0015] 1, an authentication system 1 is made up of an authentication device 10, an authentication server 20, and a gate device 30. Each device is connected to networks NW1 and NW2 such as a LAN (Local Area Network) or the Internet.

[0016] The authentication device 10 captures an image of a person to be authenticated who is present in a predetermined area, and outputs the captured image to the authentication server 20. In the first embodiment, the term "predetermined area" refers to a three-dimensional space of a predetermined range located in front of the authentication device 10.

[0017] The authentication server 20 is a computer that performs biometric authentication, and includes an authentication engine 21 and a database 22. The authentication engine 21 executes a process of matching the biometric information (or feature amounts) of the person to be authenticated, captured by the authentication device 10, with the registered biometric information (or feature amounts) of the registered person that is registered in advance in the database 22, and performs face authentication of the person to be authenticated based on the matching result.

[0018] The database 22 is a storage device that stores various information such as a biometric image, height information, and attribute information of a registrant in association with a registrant ID. The biometric information and height information of a registrant are registered in the database 22 in advance based on a request from the registrant.

[0019] For example, a person who wishes to use the authentication system 1 stands in front of a registration terminal (not shown) that has the same functions as the authentication device 10, and operates the terminal to capture an image of his or her face. The captured face image is registered in the database 22 as a registered biometric image. The registration terminal also calculates height information based on the captured image of the person, the imaging angle of the camera 107, and the distance to the person, using a height information estimation method described below. The calculated height information is registered in the database 22 as registered height information.

[0020] The gate device 30 is a passage control device that opens and closes a gate (not shown) based on control information from the authentication device 10, and controls the passage of people. When the authentication device 10 successfully authenticates a person, the gate device 30 transitions from a closed standby state that blocks the passage of people to an open state that allows the passage of people. The type of gate is not particularly limited, and examples include a flapper gate in which flappers installed on one or both sides of the passage open and close, and a turnstile gate in which three bars rotate.

[0021] 2 is a block diagram showing an example of the hardware configuration of the authentication device 10 according to the first embodiment. The authentication device 10 is a computer that performs calculations, control, and storage, and includes a processor 101, a RAM (Random Access Memory) 102, a ROM (Read Only Memory) 103, a storage 104, a communication I / F (Interface) 105, a display 106, a camera 107, a distance sensor 108, a motor 109, and a lighting device 110. The devices are connected to each other via a bus, wiring, a drive device, etc. (not shown).

[0022] The processor 101 has a function of performing predetermined calculations in accordance with programs stored in the ROM 103, storage 104, etc., and controlling each part of the authentication device 10. Furthermore, as the processor 101, a CPU (Central Processing Unit), GPU (Graphics Processing Unit), FPGA (Field Programmable Gate Array), DSP (Digital Signal Processor), ASIC (Application Specific Integrated Circuit), etc. may be used. Furthermore, one of the above examples may be used, or multiple may be used in parallel.

[0023] The RAM 102 is made up of a volatile storage medium and provides a temporary memory area necessary for the operation of the processor 101. The RAM 102 may be, for example, a D-RAM (Dynamic RAM). The ROM 103 is made up of a non-volatile storage medium and stores necessary information such as programs used in the operation of the authentication device 10. The ROM 103 may be, for example, a P-ROM (Programmable ROM).

[0024] The storage 104 is configured from a nonvolatile storage medium, and stores data and programs for operating the authentication device 10. The storage 104 is configured from, for example, an HDD (Hard Disk Drive) or an SSD (Solid State Drive).

[0025] The communication I / F 105 is a communication interface based on standards such as Ethernet (registered trademark), Wi-Fi (registered trademark), 4G, or 5G, and is a module for communicating with other devices.

[0026] The processor 101 loads a program stored in the ROM 103, the storage 104, etc. into the RAM 102 and executes it.

[0027] The display 106 is a display device that displays moving images, still images, characters, etc. The display 106 displays, for example, guide information related to authentication and authentication results. The display 106 may be a liquid crystal display, an OLED (Organic Light Emitting Diode) display, or the like.

[0028] The camera 107 is an imaging device that captures an image of a subject by receiving light incident from the subject via an optical system with a light receiving element. The camera 107 of the first embodiment captures an image of a person to be authenticated who is present in a predetermined area in front of the device. As the camera 107, a digital camera using a CMOS (Complementary Metal Oxide Semiconductor) image sensor, a CCD (Charge Coupled Device) image sensor, or the like is used so as to be suitable for image processing in the authentication device 10.

[0029] Distance sensor 108 is a measuring device that measures the distance from camera 107 to the person to be authenticated. Distance sensor 108 may be capable of optically measuring the distance from camera 107 to the person to be authenticated. Examples of distance sensors 108 that can optically measure distance include a TOF (Time Of Flight) sensor, a triangulation sensor, and a LiDAR (Light Detection and Ranging) sensor. Furthermore, a proximity sensor that detects the approach of a target without contact can also be used as distance sensor 108.

[0030] The motor 109 is a driving device that drives an object connected to a rotation shaft. In the first embodiment, the camera 107 is connected to the rotation shaft of the motor 109. The camera 107 does not have to be directly connected to the rotation shaft of the motor 109. For example, the camera 107 may be indirectly connected to the rotation shaft via a gear, a belt, or the like, and driven by the motor 109.

[0031] The illumination device 110 is a light source that emits illumination light forward. The timing of emission of illumination light by the illumination device 110 is synchronized with the timing of image capture by the camera 107.

[0032] The hardware configuration shown in Fig. 2 is an example, and other devices may be added, or some devices may not be provided. Also, some devices may be replaced with other devices having similar functions. Also, some functions of the first embodiment may be provided by other devices via a network, or the functions of the first embodiment may be distributed and realized among multiple devices. The illustrated hardware configuration can be modified as appropriate.

[0033] Fig. 3 is a front view showing the appearance of the authentication device 10 according to the first embodiment. In Fig. 3, the positional relationship of the components that make up the authentication device 10 is explained using a three-dimensional coordinate system consisting of an X-axis, a Y-axis, and a Z-axis that are orthogonal to each other. The X-axis and Y-axis are axes on a horizontal plane. The X-axis and Y-axis are orthogonal to each other. The Z-axis is an axis that is orthogonal to the horizontal plane.

[0034] 3, a display 106, a distance sensor 108, and a camera 107 are arranged from top to bottom along the center line of the authentication device 10. A pair of lighting devices 110 are also arranged on both sides of the camera 107. The center point of the light receiving area of ​​the camera 107 is located at a height H from the ground surface Gr in the vertical direction.

[0035] FIG. 4 is a perspective view illustrating the internal structure of the authentication device 10 according to the first embodiment. As shown in FIG. 4, the camera 107 is disposed in the case 112 together with the motor 109. The camera 107 is connected to the rotation axis A of the motor 109 and therefore rotates together with the rotation axis A. The rotation axis A extends in the X-axis direction. The optical axis Ax of the camera 107 moves up and down due to rotation around the rotation axis A. In the first embodiment, the imaging angle of the camera 107 means the angle of the optical axis Ax with respect to the horizontal plane.

[0036] Specifically, when motor 109 is driven, camera 107 rotates in the direction of arrow UP or arrow DW around rotation axis A. When camera 107 rotates in the direction of arrow UP, the imaging range of camera 107 moves upward. Conversely, when camera 107 rotates in the direction of arrow DW, the imaging range of camera 107 moves downward.

[0037] FIG. 5 is a flowchart showing an outline of the processing executed in the authentication system 1 according to the first embodiment.

[0038] In step S101, the authentication device 10 captures an image of a predetermined area by using the camera 107 to capture an image of the area in front of the device.

[0039] In step S102, the authentication device 10 executes a person's face detection process on the captured image. Specifically, the authentication device 10 detects an area in the captured image that matches the shape pattern of the person's face.

[0040] In step S103, the authentication device 10 determines whether or not a person's face has been detected from the captured image. If the authentication device 10 determines that a person's face has been detected (step S103: YES), the process proceeds to step S104.

[0041] On the other hand, if the authentication device 10 determines that a person's face has not been detected (step S103: NO), the process returns to step S101.

[0042] In step S104, the authentication device 10 issues an authentication subject ID of the person whose face has been detected. The authentication subject ID is identification information unique to each person.

[0043] In step S105, the authentication device 10 measures the horizontal distance from the authentication device 10 (camera 107) to the person using the distance sensor .

[0044] In step S106, the authentication device 10 calculates the height of the person based on the measured distance and the height from the ground of the camera 107. Information about the height of the camera 107 is stored in advance in, for example, the storage 104 or the ROM 103.

[0045] Fig. 6 is a schematic diagram illustrating the imaging angle and imaging range of the camera 107 when capturing an image of a person P1 in the authentication system 1 according to the first embodiment. In Fig. 6, the camera 107 is positioned so that the optical axis Ax of the camera 107 is horizontal, and the imaging angle is 0 degrees. The imaging range R1 in Fig. 6 includes the face and upper body of the person P1.

[0046] Fig. 7 shows a captured image IMG-01 captured at the imaging angle shown in Fig. 6. The center point O of the captured image IMG-01 is located below the face detection area F of person P1. The length L shown in Fig. 6 is calculated from the distance within the image from the center point O to the top of the head T of person P1.

[0047] In step S107, the authentication device 10 identifies the position of the person's face in the captured image. In the example of Fig. 7, the position of the center point of the face detection area F of person P1 is the position of the person's face.

[0048] In step S108, the authentication device 10 drives the camera 107 so that the position of the face of the person identified in step S107 is located at the center point of the captured image.

[0049] In step S109, the authentication device 10 captures an image in front of the device using the camera 107, thereby obtaining a captured image including the face of the person.

[0050] In step S110, the authentication device 10 extracts a facial image of the person from the captured image acquired in step S109 and transmits the facial image to the authentication server 20. As a result, the authentication engine 21 of the authentication server 20 compares the facial image with registered facial images pre-registered in the database 22, and performs facial authentication of the person. When the authentication server 20 completes facial authentication, it transmits the authentication result to the authentication device 10. The authentication result includes an authentication score indicating the degree of match between the facial image of the person and the registered facial image of the registrant.

[0051] FIG. 8 is a schematic diagram illustrating the imaging angle and imaging range of the camera 107 when capturing an image of a person P1 in the authentication system 1 according to the first embodiment.

[0052] In Fig. 8, the optical axis Ax of the camera 107 is driven upward, and the imaging angle changes from 0 degrees to +θ1, compared to the case of Fig. 6. Therefore, the imaging range R2 of the camera 107 in Fig. 8 is moved vertically upward from the imaging range R1 shown in Fig. 6.

[0053] FIG. 9 shows captured image IMG-02 captured at the imaging angle shown in FIG. 8. The center point O of captured image IMG-02 coincides with the center point of the face detection area F of person P1. This makes it possible to acquire a high-quality face image from the face detection area F of person P1, which can improve the accuracy of face recognition. Furthermore, the distance L between the center point O and the top of the head T of person P1 can be calculated from the imaging angle, the angle of view of camera 107, the horizontal distance, and the in-image distance. Therefore, even if the imaging angle of camera 107 is changed, the height of the person's head can be easily calculated.

[0054] FIG. 10 is a schematic diagram illustrating the imaging angle and imaging range of the camera 107 when capturing an image of a person P2 in the authentication system 1 according to the first embodiment.

[0055] Since the height of person P2 is shorter than that of person P1, in Fig. 10, the optical axis Ax of camera 107 is driven downward and the imaging angle changes from 0 degrees to -θ2 compared to the case of Fig. 6. Therefore, the imaging range R3 of camera 107 in Fig. 10 is moved vertically downward from the imaging range R1 shown in Fig. 6.

[0056] Fig. 11 shows a captured image IMG-03 captured at the imaging angle shown in Fig. 10. As in the case of Fig. 9, the center point O of the captured image IMG-03 coincides with the center point of the face detection area F of person P2. This makes it possible to acquire a high-quality face image from the face detection area F of person P2, which can improve the accuracy of face recognition. Furthermore, the distance L between the center point O and the top of the head T of person P2 can be calculated from the imaging angle, the angle of view of camera 107, the distance in the horizontal direction, and the distance within the image.

[0057] In step S111, the authentication device 10 determines whether or not the person is a registrant based on the authentication result received from the authentication server 20. Here, if the authentication device 10 determines that the person is a registrant (step S111: YES), the process proceeds to step S112.

[0058] On the other hand, if the authentication device 10 determines that the person is not a registered person (step S111: NO), it displays an authentication error message on the display 106 (step S118), and the process ends.

[0059] In step S112, the authentication device 10 acquires registered height information relating to the registrant from the authentication server 20.

[0060] In step S113, the authentication device 10 compares the height value calculated in step S106 with the registered height information and calculates a comparison score indicating the degree of height match. The biometric authentication score and the height comparison score are temporarily stored in, for example, RAM or storage in association with the authentication subject ID.

[0061] In step S114, the authentication device 10 calculates a total score from the authentication score included in the authentication result received from the authentication server 20 and the matching score calculated in step S111. Note that the method for calculating the total score can be determined arbitrarily.

[0062] In step S115, the authentication device 10 determines whether the calculated total score is equal to or greater than a predetermined threshold. If the authentication device 10 determines that the total score is equal to or greater than the predetermined threshold (step S115: YES), the process proceeds to step S116.

[0063] On the other hand, if the authentication device 10 determines that the total score is less than the predetermined threshold (step S115: NO), it displays an authentication error message on the display 106 (step S118), and the process ends.

[0064] In step S116, the authentication device 10 displays a message indicating successful authentication on the display 106, and outputs control information to the gate device 30.

[0065] In step S117, the gate device 30 opens the gate based on the control information from the authentication device 10.

[0066] As described above, according to the authentication system 1 of the first embodiment, even if the imaging angle of the camera 107 is changed, the height of a predetermined part of a person can be easily estimated based on the imaging angle of the camera 107 when the captured image was taken. Furthermore, by driving the camera 107, a facial image used for biometric authentication can be captured at an appropriate imaging angle. Furthermore, because the imaging angle information is managed by the control system of the authentication device 10, even if the imaging range is changed by driving the camera 107, the height can be calculated based on the imaging angle after the change.

[0067] Furthermore, according to the authentication system 1 of the first embodiment, the height of a person is estimated based on the in-image distance from the center of the captured image to the position of a predetermined part of the person, the horizontal distance from the person to the authentication device 10, and the imaging angle. Therefore, the height of a person can be estimated with high accuracy.

[0068] The authentication system 1 according to the first embodiment can obtain, through simple calculations, a person's height information (body height information), which is information useful for identifying an individual, and can perform two-factor authentication that combines face authentication (first biometric authentication) using a biometric image of the person and a registered biometric image, and authentication (second biometric authentication) using height information calculated from the image and registered height information stored in the database 22. This allows the authentication system 1 to provide highly accurate personal authentication with a low probability of false acceptance or false rejection.

[0069] Furthermore, the authentication system 1 according to the first embodiment performs face authentication using a face image and a registered face image as the first biometric authentication. The face image can be acquired from a captured image, and has the advantage of being able to easily calculate height information to a predetermined part such as the top of the head.

[0070] Furthermore, in the authentication system 1 according to the first embodiment, the angle of the optical axis of the camera 107 (imaging unit) relative to the horizontal plane is used as the imaging angle, which makes it easy to calculate the predetermined part of the subject. [Second embodiment]

[0071] The authentication system 1 according to the second embodiment will be described below. The following mainly focuses on the differences from the first embodiment, and explanations of common parts will be omitted or simplified.

[0072] Fig. 12 is a block diagram showing an example of the hardware configuration of the authentication device 10 according to the second embodiment. Fig. 13 and Fig. 14 are schematic diagrams illustrating the imaging method and imaging range of the authentication device 10 according to the second embodiment.

[0073] As shown in FIG. 12, the authentication device 10 differs from the hardware configuration shown in FIG.

[0074] The rotating mirror 111 is a member that is provided so as to be movable in the vertical direction with respect to the horizontal, and that reflects light that has entered from outside the authentication device 10 toward the camera 107 .

[0075] 13 and 14, the rotating mirror 111 is connected to a rotation shaft 109a of the motor 109 and rotates together with the rotation shaft 109a. Specifically, the camera 107 rotates integrally with the motor 109 about the rotation shaft 109a when the motor 109 is driven. Note that the rotating mirror 111 does not have to be directly connected to the rotation shaft 109a of the motor 109. For example, the camera 107 may be indirectly connected to the rotation shaft 109a via a gear, a belt, or the like, and driven by the motor 109.

[0076] Unlike the first embodiment, the camera 107 is not connected to the motor 109, but is fixed inside the authentication device 10. The lens surface of the camera 107 is disposed vertically downward so as to face the reflecting surface of the rotating mirror 111.

[0077] 13 shows a state in which the rotating mirror 111 is tilted at 45 degrees with respect to the horizontal plane HP. The imaging angle of the camera 107 is the angle at which the optical axis Ax of the camera 107 intersects with the horizontal plane HP, which is 0 degrees.

[0078] On the other hand, in Fig. 14, the rotating mirror 111 is rotated more clockwise than in the state of Fig. 13. Therefore, the angle at which the optical axis Ax of the camera 107 intersects with the horizontal plane HP is θ3. In other words, the imaging angle of the camera 107 in Fig. 14 is θ3.

[0079] 15 is a flowchart showing an outline of the processing executed in the authentication system 1 according to the second embodiment. The processing in FIG. 15 differs only partially from the flowchart shown in FIG.

[0080] In step S201, the authentication device 10 drives the rotating mirror 111 so that the position of the face of the person identified in step S107 is located at the center of the captured image. That is, the authentication device 10 adjusts the relative position between the person's face and the rotating mirror 111 by rotating the rotating mirror 111. This allows the authentication device 10 to capture an image that captures the entire face of the person to be authenticated. Then, the process proceeds to step S109. The process from step S109 onwards is the same as that in FIG. 5.

[0081] As described above, according to the authentication system 1 of the second embodiment, there is no need to drive the camera 107 itself in order to change the imaging angle of the camera 107. By driving the rotating mirror 111 instead of the camera 107, it is possible to capture a face image used for biometric authentication at an appropriate imaging angle. In addition, information on the rotation angle of the rotating mirror 111 is managed by the control system of the authentication device 10. Because the imaging angle can be determined from the rotation angle of the rotating mirror 111, the height of a predetermined part of the person to be authenticated in the captured image can be easily estimated, as in the first embodiment. [Third embodiment]

[0082] The authentication system 1 according to the third embodiment will be described below. The following mainly focuses on the differences from the second embodiment, and explanations of common parts will be omitted or simplified.

[0083] Fig. 16 is a block diagram showing an example of the hardware configuration of the authentication device 10 according to the third embodiment. As shown in Fig. 16, the authentication device 10 includes a first camera 107A and a second camera 107B instead of the camera 107 shown in Fig. 12.

[0084] First camera 107A is an imaging device that captures an image overlooking a predetermined area. As first camera 107A, a digital camera using a CMOS image sensor, a CCD image sensor, or the like is used so as to be suitable for image processing in authentication device 10.

[0085] Second camera 107B is an imaging device consisting of an infrared light emitting device (not shown) and an infrared light camera (not shown), and captures an image of a person's eyes using infrared light. The infrared light emitting device includes a light emitting element that emits infrared light, such as an infrared LED. The wavelength of the infrared light irradiated from the infrared light emitting device may be, for example, in the near-infrared region of about 800 nm.

[0086] The infrared camera includes a light-receiving element configured to be sensitive to infrared light. The infrared camera may be a digital camera using a CMOS image sensor, a CCD image sensor, or the like. An infrared light irradiation device irradiates a person's eye with infrared light, and the infrared light reflected by the iris is captured by the infrared camera to obtain an image of the eye, including an iris image used for iris authentication. Obtaining an iris image captured with infrared light allows for a high-contrast image to be obtained regardless of the color of the iris, and also reduces the influence of reflection from the cornea.

[0087] 17 and 18 are schematic diagrams illustrating the imaging angle and imaging range of the authentication device 10 according to the third embodiment. As shown in Fig. 17 and Fig. 18, the first camera 107A is disposed in the horizontal direction. The first camera 107A is not connected to the rotation shaft of the motor 109. In other words, the imaging angle of the first camera 107A is constant.

[0088] On the other hand, the light receiving surface of second camera 107B is disposed vertically downward so as to face the reflecting surface of rotating mirror 111. Second camera 107B is connected to rotation shaft 109a of motor 109 and can rotate together with rotation shaft 109a. FIG. 17 shows the state before second camera 107B is driven. On the other hand, FIG. 18 shows the state after second camera 107B has rotated counterclockwise from the state shown in FIG. 17. The angle at which the optical axis Ax of second camera 107B intersects with the horizontal plane HP is -θ4. That is, the imaging angle of second camera 107B in FIG. 18 is -θ4.

[0089] Furthermore, the imaging range R21 of first camera 107A is wider than the imaging range R22 of second camera 107B. In other words, the angle of view of first camera 107A is wider than the angle of view of second camera 107B. Authentication device 10 may move imaging range R22 of iris camera 12 by rotating rotating mirror 111 using a motor. Authentication device 10 moves imaging range R22 of second camera 107B by changing the tilt angle of rotating mirror 111 using motor 109. For example, authentication device 10 can move imaging range R22 of second camera 107B up and down along the vertical direction by rotating rotating mirror 111.

[0090] In addition, in order to perform face authentication and iris authentication, it is assumed that the face image and iris image of the registrant are registered in advance in the database 22 of the third embodiment. When requesting authentication from the authentication server 20, the authentication device 10 transmits the face image and iris image of the person to be authenticated to the authentication server 20.

[0091] As described above, according to the authentication system 1 of the third embodiment, it is possible to further acquire an iris image of a person as biometric information, and therefore it is possible to perform three-factor authentication that further combines iris authentication with face authentication and authentication based on height information. [Fourth embodiment]

[0092] The authentication system 1 according to the fourth embodiment will be described below. The following mainly focuses on the differences from the first embodiment, and the description of the common parts will be omitted or simplified.

[0093] 19 is a flowchart showing an outline of the processing executed by the authentication system 1 according to the fourth embodiment. The processing in FIG. 19 differs only partially from the flowchart shown in FIG.

[0094] In step S301, the authentication device 10 determines whether the distance measured in step S105 is equal to or less than a predetermined threshold. If the authentication device 10 determines that the distance is equal to or less than the threshold (step S301: YES), the process proceeds to step S302.

[0095] On the other hand, if the authentication device 10 determines that the distance exceeds the threshold value (step S301: NO), the process proceeds to step S304.

[0096] In step S302, when the authentication device 10 selects the biometric authentication mode as the setting mode for the image capture process, it drives the camera 107 to have an image capture angle corresponding to the biometric authentication mode and executes the image capture process. For example, in the biometric authentication mode, it captures an image at a first image capture angle in which the center of the captured image is set to the face of the person to be authenticated.

[0097] In step S303, the authentication device 10 acquires a face image of the person from the captured image taken in step S302, and transmits the face image to the authentication server 20. As a result, the authentication engine 21 of the authentication server 20 performs face authentication of the person by comparing the face image with registered face images pre-registered in the database 22. When the authentication server 20 completes face authentication, it transmits the authentication result to the authentication device 10. Then, the process proceeds to step S306.

[0098] In this way, the authentication server 20 is configured to perform face authentication based on a face image extracted from an image captured in biometric authentication mode, thereby improving authentication accuracy.

[0099] In step S304, when the height estimation mode is selected as the setting mode for the imaging process, the authentication device 10 drives the camera 107 to have an imaging angle corresponding to the height estimation mode, and executes the imaging process. For example, in the height estimation mode, imaging is performed at a second imaging angle in which the center of the captured image is set at the top of the head of the person to be authenticated.

[0100] By using the captured image captured in the height estimation mode for the height estimation process, the cost of calculation is reduced.

[0101] In step S305, the authentication device 10 calculates the height of the person from the distance measured in step S105. Specifically, as described in Fig. 6, the authentication device 10 calculates the length L from the center coordinate position of the captured image to the top of the face detection area F, and calculates the height of the person by adding the height H to the center point of the camera 107 to the length L. Then, the process proceeds to step S306.

[0102] In step S306, the authentication device 10 determines whether or not the image capturing process has been performed in both the biometric authentication mode and the height estimation mode. If the authentication device 10 determines that the image capturing process has been performed in both modes (step S306: YES), the process proceeds to step S111. The process from step S111 onwards is the same as in the first embodiment.

[0103] On the other hand, if the authentication device 10 determines that the image capturing process has not been performed in both modes (step S306: NO), the process returns to step S105. The processes of step S105 and steps S301 to S306 are repeatedly performed until the image capturing process in the two modes is completed. Note that with regard to the biometric authentication process (step S303), the process from the second time onwards may be omitted based on the result of the first authentication.

[0104] In the above flowchart, the biometric authentication mode is executed when the distance is equal to or less than the threshold, and the height estimation mode is executed when the distance exceeds the threshold, but the set mode to be executed may be reversed, and the threshold may also be set arbitrarily. That is, the height estimation mode may be executed when the distance is equal to or less than the threshold, and the biometric authentication mode may be executed when the distance exceeds the threshold.

[0105] In the above-described flowchart, biometric authentication is performed on the condition that the distance from the authentication device 10 to the person to be authenticated is equal to or less than a threshold. The execution condition for biometric authentication is constant regardless of the distance. However, the processing may be partially modified so that the threshold in at least one of the biometric authentication mode (first biometric authentication) and the height estimation mode (second biometric authentication) is changed depending on the distance. Generally, the closer the distance, the higher the quality of the facial image that can be acquired. Conversely, the farther the distance, the lower the quality of the facial image that can be acquired. Therefore, by changing the threshold depending on the distance, the execution condition for biometric authentication is changed according to the quality of the facial image used. This can further improve the accuracy of biometric authentication.

[0106] As described above, the authentication system 1 according to the fourth embodiment can select a setting mode corresponding to an appropriate imaging angle depending on the distance from the authentication device 10 to the person to be authenticated, and can execute imaging processing while switching the imaging angle, thereby further improving the accuracy of face authentication. [Fifth embodiment]

[0107] The authentication system 1 according to the fifth embodiment will be described below. The following mainly focuses on the differences from the first embodiment, and explanations of common parts will be omitted or simplified.

[0108] Fig. 20 is a flowchart showing an outline of the processing executed in the authentication system 1 according to the fifth embodiment. The processing in Fig. 20 may be executed within the processing in Fig. 5, or may be executed in parallel with the processing in Fig. 5.

[0109] In step S401, the authentication device 10 captures an image of a person using the camera 107 whose imaging angle has been changed.

[0110] In step S402, the authentication device 10 measures the horizontal distance from the authentication device 10 (camera 107) to the person using the distance sensor .

[0111] In step S403, the authentication device 10 calculates the height of the person based on the captured image, the imaging angle, and the distance.

[0112] In step S404, the authentication device 10 stores the calculated height as time-series data in a storage area, such as the storage 104 or the database 22 of the authentication server 20.

[0113] In step S405, the authentication device 10 determines whether or not acquisition of the time-series data is complete. If the authentication device 10 determines that acquisition of the time-series data is complete (step S405: YES), the process proceeds to step S406.

[0114] On the other hand, if the authentication device 10 determines that acquisition of the time-series data has not been completed (step S405: NO), the process returns to step S401. The processes of steps S401 to S404 are repeatedly executed at predetermined intervals.

[0115] In step S406, the authentication device 10 analyzes the time-series data of height. The time-series data is data that indicates the change (transition) in the height of a person over time.

[0116] In step S407, the authentication device 10 creates gait data of the person based on the analysis result in step S406, and ends the process. Normally, when a person moves on foot, the height of the top of the head changes in the vertical direction. Therefore, by calculating the height of a specific part of the person multiple times at a specific cycle, the person's gait can be determined.

[0117] As described above, according to the authentication system 1 of the fifth embodiment, by acquiring the person's height as time-series data, it is possible to easily create gait data of the person. Furthermore, by calculating the person's height multiple times, it is possible to estimate the person's height with high accuracy. [Sixth embodiment]

[0118] The authentication system 1 according to the sixth embodiment will be described below. The following mainly focuses on the differences from the fifth embodiment, and explanations of common parts will be omitted or simplified.

[0119] 21 is a flowchart showing an outline of the processing executed by the authentication system 1 according to the sixth embodiment. The processing in FIG. 21 differs only partially from the flowchart shown in FIG.

[0120] In step S501, the authentication device 10 determines whether the time-series data matches a specific displacement pattern. If the authentication device 10 determines that the time-series data matches a specific displacement pattern (step S501: YES), the process proceeds to step S502.

[0121] On the other hand, if the authentication device 10 determines that the time-series data does not match the specific displacement pattern (step S501: NO), the process ends.

[0122] In step S502, the authentication device 10 identifies the state of the person while moving based on the matching displacement pattern. The state of the person while moving corresponds to a state in which walking is difficult, a state in which a specific item is used while moving, etc. Examples of the item include a wheelchair, a walking stick, a push cart, etc.

[0123] Specifically, if a person uses a wheelchair to move around, the range of change in the height of the person's head over time is expected to be smaller than when walking normally. On the other hand, if a person uses a cane or is disabled, the range of change in the height of the person's head over time is expected to be larger than when walking normally. Therefore, by registering the relationship between the state of the person when moving and the time change in the height of a specific part of the person as a displacement pattern, the state of the person can be identified from the time series data.

[0124] In step S503, the authentication device 10 notifies an attendant depending on the state of the person during movement. For example, if the authentication device 10 determines that the person is using a wheelchair, it is preferable that the authentication device 10 outputs a notification to call an attendant managing the facility to the entrance / exit gate.

[0125] As described above, the authentication system 1 according to the sixth embodiment can identify the items a person uses for transportation and the state of the person based on the change over time in the height of a specific part of the person. This makes it possible to automatically detect people who require assistance from an attendant when passing through a gate and being authenticated, and to respond promptly. [Seventh embodiment]

[0126] 22 is a functional block diagram showing the overall configuration of an information processing device 100 according to the seventh embodiment. The information processing device 100 includes an imaging unit 100A, a driving unit 100B, and an estimation unit 100C. The imaging unit 100A captures an image of an object and generates a captured image. The driving unit 100B changes the imaging angle of the imaging unit 100A. The estimation unit 100C estimates height information of a predetermined part of the object based on the captured image of the object and the imaging angle.

[0127] According to the seventh embodiment, an information processing device 100 capable of acquiring a biometric image suitable for biometric authentication is provided. [Modified embodiment]

[0128] This disclosure is not limited to the above-described embodiments and can be modified as appropriate within the scope of the spirit of this disclosure. For example, an example in which part of the configuration of one embodiment is added to another embodiment, or an example in which part of the configuration of another embodiment is replaced with another embodiment, is also an embodiment of this disclosure.

[0129] In the first embodiment described above, biometric authentication and height estimation are performed based on captured images taken by the same camera, but different image capture devices may be used depending on the purpose of the image. Specifically, if the authentication device 10 is equipped with a camera for authentication and a camera for height estimation, biometric authentication based on a first captured image taken by the authentication camera and height information estimation processing based on a second captured image taken by the height estimation camera may be performed in parallel.

[0130] In the first embodiment described above, the height information estimation process is performed only once. However, the height information estimation process may be performed each time the imaging angle is changed. That is, after the height information has been estimated once, if the imaging angle changes as a result of the camera 107 being driven, the height information is acquired again. For example, when a person moves toward a gate, the distance between the camera 107 and the person gradually decreases. In such a case, it is preferable to perform two-factor authentication based on the most recent captured image and imaging angle. This further improves authentication accuracy.

[0131] In the above-described first to seventh embodiments, the example of entrance and exit using a gate was given, but the present invention can also be applied to situations where individuals are authenticated for payments at financial institutions or retail stores, entrance and exit management at hotels or condominiums, keyless entry systems for cars, etc.

[0132] In the above-described first to seventh embodiments, the authentication server 20 external to the authentication device 10 is provided with the authentication engine 21 and database 22 for extracting biometric information and calculating a matching score, but the functions of the authentication engine 21 and database 22 may be provided inside the authentication device 10.

[0133] The scope of each embodiment also includes a processing method in which a program that operates the configuration of the embodiment to realize the functions of the above-described embodiments is recorded on a storage medium, the program recorded on the storage medium is read as code, and the program is executed on a computer. That is, a computer-readable storage medium is also included in the scope of each embodiment. Furthermore, not only the storage medium on which the above-described program is recorded, but also the program itself is included in each embodiment. Furthermore, one or more components included in the above-described embodiments may be circuits such as ASICs or FPGAs configured to realize the functions of each component.

[0134] Examples of the storage medium that can be used include a floppy disk, a hard disk, an optical disk, a magneto-optical disk, a CD (Compact Disk)-ROM, a magnetic tape, a non-volatile memory card, and a ROM. Furthermore, the scope of each embodiment is not limited to programs that execute processing by themselves recorded on the storage medium, but also includes programs that execute processing by operating on an OS (Operating System) in cooperation with other software and functions of an expansion board.

[0135] The services realized by the functions of the above-described embodiments can also be provided to users in the form of SaaS (Software as a Service).

[0136] It should be noted that the above-described embodiments are merely examples of specific embodiments for carrying out this disclosure, and the technical scope of this disclosure should not be interpreted as being limited by these embodiments. In other words, this disclosure can be carried out in various forms without departing from its technical idea or main features.

[0137] A part or all of the above-described embodiments can be described as, but not limited to, the following supplementary notes.

[0138] (Appendix 1) an imaging unit that captures an image of an object and generates a captured image; a driving unit that changes the imaging angle of the imaging unit; an estimation unit that estimates height information of a predetermined part of the target based on the captured image and the imaging angle; An information processing device comprising:

[0139] (Appendix 2) the driving unit changes the imaging angle by driving the imaging unit; 10. The information processing device according to claim 1.

[0140] (Appendix 3) the imaging unit includes a mirror that reflects light incident from the object toward a light receiving unit of the imaging unit, the driving unit changes the imaging angle by driving the mirror; 10. The information processing device according to claim 1.

[0141] (Appendix 4) an acquisition unit that acquires a distance from the object to the imaging unit; the estimation unit estimates the height information based on the distance, the imaging angle, and the position of the predetermined part in the captured image. 4. An information processing device according to any one of claims 1 to 3.

[0142] (Appendix 5) the position of the predetermined portion is determined by a distance within the image from a center point in the captured image. 5. The information processing device according to claim 4.

[0143] (Appendix 6) a storage unit that stores a registered biometric image and registered height information of a registered person; an authentication unit that performs first biometric authentication using the registered biometric image and the biometric image of the target included in the captured image, and second biometric authentication using the registered height information and the height information; 6. The information processing device according to claim 4 or 5, further comprising:

[0144] (Appendix 7) The authentication unit changes a threshold value for at least one of the first biometric authentication and the second biometric authentication based on the distance. 7. The information processing device according to claim 6.

[0145] (Appendix 8) the registered biometric image is a registered face image of the registrant, the imaging unit captures the captured image including a facial image of the target; the authentication unit performs face authentication using the face image and the registered face image as the first biometric authentication. 8. The information processing device according to claim 6 or 7.

[0146] (Appendix 9) the registered biometric image is a registered face image and a registered iris image of the registrant, the imaging unit includes a first imaging unit that captures the captured image including a face image of the target and a second imaging unit that captures an iris image of the target, the authentication unit performs, as the first biometric authentication, face authentication using the face image and the registered face image, and iris authentication using the iris image and the registered iris image, 8. The information processing device according to claim 6 or 7.

[0147] (Appendix 10) The driving unit changes the imaging angle in accordance with the distance. 10. An information processing device according to any one of Supplementary Notes 6 to 9.

[0148] (Appendix 11) When the distance is equal to or greater than a predetermined threshold, the imaging unit captures an image at a first imaging angle in which the center of the captured image is set to the face of the subject, and when the distance is less than the threshold, the imaging unit captures an image at a second imaging angle in which the center of the captured image is set to the top of the head of the subject. 11. The information processing device according to claim 10.

[0149] (Appendix 12) When the distance is less than a predetermined threshold, the imaging unit captures an image at a first imaging angle in which the center of the captured image is set to the face of the subject, and when the distance is equal to or greater than the threshold, the imaging unit captures an image at a second imaging angle in which the center of the captured image is set to the top of the head of the subject. 11. The information processing device according to claim 10.

[0150] (Appendix 13) The predetermined part is any one of the top of the head, eyes, nose, ears, mouth, and chin. 13. An information processing device according to any one of appendices 1 to 12.

[0151] (Appendix 14) the estimation unit re-estimates the height information when the drive unit changes the imaging angle after estimating the height information; 14. An information processing device according to any one of appendices 1 to 13.

[0152] (Appendix 15) The estimation unit estimates a gait of the target based on a time change in the height information. An information processing device according to any one of appendices 1 to 14.

[0153] (Appendix 16) The estimation unit estimates an item used by the subject for movement based on a time change in the height information. An information processing device according to any one of appendices 1 to 14.

[0154] (Appendix 17) The imaging angle is the angle of the optical axis of the imaging unit with respect to a horizontal plane. 17. An information processing device according to any one of appendices 1 to 16.

[0155] (Appendix 18) capturing an image of an object using an imaging device to generate a captured image; changing an imaging angle of the imaging device; estimating height information of a predetermined part of the object based on the captured image and the imaging angle; An information processing method comprising:

[0156] (Appendix 19) On the computer, capturing an image of an object using an imaging device to generate a captured image; changing an imaging angle of the imaging device; estimating height information of a predetermined part of the object based on the captured image and the imaging angle; A recording medium on which a program for executing the above is recorded. [Explanation of symbols]

[0157] 1. Authentication system 10. Authentication device 101 Processor 102 RAM 103···ROM 104 Storage 105 Communication I / F 106···Display 107···Camera 107A···1st camera 107B···Second camera 108···Motor 109...Distance sensor 110 Lighting equipment 111···Rotating mirror 20 Authentication Server 21 Authentication engine (authentication unit) 22. Database (storage section) 30. Gate device 100 Information processing device 100A···Image capture unit 100B···Drive unit 100C...Estimation part

Claims

1. an imaging unit that captures an image of an object and generates a captured image; a driving unit that changes the imaging angle of the imaging unit; an estimation unit that estimates height information of a predetermined part of the target based on the captured image and the imaging angle; an acquisition unit that acquires a distance from the object to the imaging unit; a storage unit that stores a registered biometric image and registered height information of a registered person; an authentication unit that performs first biometric authentication using the registered biometric image and the biometric image of the target included in the captured image, and second biometric authentication using the registered height information and the height information; Equipped with the estimation unit estimates the height information based on the distance, the imaging angle, and the position of the predetermined part in the captured image; the driving unit changes the imaging angle in accordance with the distance, When the distance is equal to or greater than a predetermined threshold, the imaging unit captures an image at a first imaging angle in which the center of the captured image is set to the face of the subject, and when the distance is less than the threshold, the imaging unit captures an image at a second imaging angle in which the center of the captured image is set to the top of the head of the subject.

2. the driving unit changes the imaging angle by driving the imaging unit; The information processing device according to claim 1 .

3. the imaging unit includes a mirror that reflects light incident from the object toward a light receiving unit of the imaging unit, the driving unit changes the imaging angle by driving the mirror; The information processing device according to claim 1 .

4. An imaging unit that captures an image of an object and generates a captured image; a driving unit that changes the imaging angle of the imaging unit; an estimation unit that estimates height information of a predetermined part of the target based on the captured image and the imaging angle; an acquisition unit that acquires a distance from the object to the imaging unit; a storage unit that stores a registered biometric image and registered height information of a registered person; an authentication unit that performs first biometric authentication using the registered biometric image and the biometric image of the target included in the captured image, and second biometric authentication using the registered height information and the height information; Equipped with the estimation unit estimates the height information based on the distance, the imaging angle, and the position of the predetermined part in the captured image; the driving unit changes the imaging angle in accordance with the distance, When the distance is less than a predetermined threshold, the imaging unit captures an image at a first imaging angle in which the center of the captured image is set to the face of the subject, and when the distance is equal to or greater than the threshold, the imaging unit captures an image at a second imaging angle in which the center of the captured image is set to the top of the head of the subject.

5. A step in which a computer captures an image of an object using an imaging device and generates a captured image; changing an imaging angle of the imaging device by the computer; a step in which the computer estimates height information of a predetermined part of the object based on the captured image and the imaging angle; The computer acquires a distance from the object to the imaging device; a step of storing a registered biometric image and registered height information of the registered person by the computer; a step in which the computer executes first biometric authentication using the registered biometric image and the biometric image of the target included in the captured image, and second biometric authentication using the registered height information and the height information; Equipped with In the estimating step, the height information is estimated based on the distance, the imaging angle, and the position of the predetermined part in the captured image; In the changing step, the imaging angle is changed according to the distance, In the generating step, if the distance is equal to or greater than a predetermined threshold, an image is captured at a first shooting angle in which the center of the captured image is set to the face of the subject, and if the distance is less than the threshold, an image is captured at a second shooting angle in which the center of the captured image is set to the top of the head of the subject.

6. On the computer, capturing an image of an object using an imaging device to generate a captured image; changing an imaging angle of the imaging device; estimating height information of a predetermined part of the object based on the captured image and the imaging angle; obtaining a distance from the object to the imaging device; storing a registered biometric image and registered height information of the registered person; performing a first biometric authentication using the registered biometric image and the biometric image of the target included in the captured image, and a second biometric authentication using the registered height information and the height information; Execute In the estimating step, the height information is estimated based on the distance, the imaging angle, and the position of the predetermined part in the captured image; In the changing step, the imaging angle is changed according to the distance, In the generating step, if the distance is equal to or greater than a predetermined threshold, an image is captured at a first shooting angle in which the center of the captured image is set to the face of the subject, and if the distance is less than the threshold, an image is captured at a second shooting angle in which the center of the captured image is set to the top of the head of the subject.

Images