Update notification device, authentication device, update notification method, and program

Abstract

The present invention makes it possible to prompt a user to update a registered image at an appropriate timing.　A face image acquisition means (21) acquires a face image of an authentication target person from a captured image from an imaging device (50). An authentication means (22) compares the acquired face image of the authentication target person and a registered image, and executes authentication with respect to the authentication target person. If the authentication succeeds, a calculation means (31) compares the face image of the authentication target person and a face image from when the authentication target person has succeeded at authentication in the past, and calculates a score. A determination means (32) determines whether to prompt the authentication target person to update the registered image on the basis of the calculated score. A notification means (33) transmits a notification prompting the authentication target person to update the registered image.

Description

[Technical Field]

[0001] The present disclosure relates to an update notification device, an authentication device, an update notification method, and a computer-readable medium. [Background technology]

[0002] As a related technique, Patent Document 1 discloses a facial authentication system. In the facial authentication system described in Patent Document 1, a facial authentication device transmits a facial image of a person to be authenticated to an authentication server. The authentication server compares the facial image of the person to be authenticated with registered facial images registered in a registrant database. If the comparison score is equal to or greater than a predetermined threshold, the authentication server identifies the person in the registered facial image as the person to be authenticated.

[0003] The authentication server aggregates the matching scores for each registrant and calculates the average score. Based on the average score, the authentication server extracts authenticated individuals with low scores as users who will be candidates for facial image updating. For example, the authentication server extracts users whose average score is slightly lower (e.g., 0.8) than the threshold for successful facial recognition (e.g., 0.75) as users who will be candidates for facial image updating. The authentication server extracts several images of authenticated individuals whose facial recognition has been successful in the past as candidate images. The administrator selects the most suitable candidate image from among the candidate images. The authentication server updates the registered image in the registrant database with the candidate image selected by the administrator. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2021-157649 Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, a registered image is updated based on a matching score between the registered image and the face image of the person to be authenticated. In Patent Document 1, by identifying users whose faces have changed due to aging or other reasons and whose scores tend to be low, it is possible to perform an update process for users who require updating. However, in Patent Document 1, the face image taken at the time of authentication is used as the registered image. For this reason, if the related technology described in Patent Document 1 is applied to a case where the registered image is taken in an environment different from that of the person to be authenticated, the matching score between the registered image and the face image of the person to be authenticated may decrease depending on the environment, etc., and it may be determined that an update is necessary unnecessarily.

[0006] In view of the above circumstances, the present disclosure aims to provide an update notification device, an authentication device, an update notification method, and a computer-readable medium that can prompt a user to update a registered image at an appropriate time. [Means for solving the problem]

[0007] To achieve the above object, the present disclosure provides, as a first aspect, an update notification device. The update notification device includes: a calculation means for, when authentication of a face image of a person to be authenticated included in an image captured by an imaging device is successful, comparing the face image of the person to be authenticated or a feature amount extracted from the face image with a face image or the feature amount of the person to be authenticated when the person to be authenticated has been successfully authenticated in the past, and calculating a score indicating the degree of match; a decision means for deciding, based on the score, whether to prompt the person to be authenticated to update a registered image used for the authentication; and a notification means for, when it is decided to prompt the person to be authenticated to update the registered image, sending a notification prompting the person to be authenticated to update the registered image.

[0008] The present disclosure provides, as a second aspect, an authentication device including: a facial image acquisition means for acquiring a facial image of a person to be authenticated from a captured image acquired by an imaging device that captures an image of the person to be authenticated; an authentication means for comparing the acquired facial image of the person to be authenticated or feature amounts extracted from the facial image with a registered image of a registrant or feature amounts extracted from the registered image, and authenticating the person to be authenticated; a calculation means for, if the authentication is successful, comparing the acquired facial image or feature amounts of the person to be authenticated with a facial image or feature amounts of the person to be authenticated when the authentication is successful in the past, and calculating a score indicating a degree of match; a decision means for deciding, based on the score, whether to prompt the person to be authenticated to update the registered image; and a notification means for, if it is decided to prompt the person to be authenticated to update the registered image, sending a notification prompting the person to be authenticated to update the registered image.

[0009] The present disclosure provides, as a third aspect, an update notification method, which includes, when authentication of a face image of a person to be authenticated included in an image captured by an imaging device is successful, comparing the face image of the person to be authenticated or feature amounts extracted from the face image with face images or feature amounts of the person to be authenticated when the person to be authenticated was successfully authenticated in the past, calculating a score indicating the degree of match, determining based on the score whether to prompt the person to be authenticated to update a registered image used for the authentication, and, when it is determined to prompt the person to be authenticated to update the registered image, transmitting a notification to the person to be authenticated to prompt the person to update the registered image.

[0010] In a fourth aspect, the present disclosure provides a computer-readable medium storing a program for causing a computer to execute a process including, when authentication of a face image of a person to be authenticated included in an image captured by an imaging device is successful, comparing the face image of the person to be authenticated or feature amounts extracted from the face image with face images or feature amounts of the person to be authenticated when the person to be authenticated has previously been successfully authenticated, calculating a score indicating the degree of match, determining based on the score whether to prompt the person to be authenticated to update a registered image used for the authentication, and, if it is determined that the person to be authenticated should update the registered image, sending a notification to the person to be authenticated to prompt the person to update the registered image. [Effects of the Invention]

[0011] This disclosure The update notification device, authentication device, update notification method, and computer-readable medium according to the present invention are Users can be prompted to update their registered images at the appropriate time. do. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a block diagram illustrating an authentication system including an authentication device according to the present disclosure. [Figure 2] 1 is a block diagram illustrating an authentication system including an authentication device according to an embodiment of the present disclosure. [Figure 3] FIG. 2 is a diagram showing an example of face information stored in a face information DB. [Figure 4] 10 is a flowchart showing an operation procedure in the authentication device. [Figure 5] FIG. 1 is a schematic diagram illustrating face recognition. [Figure 6] FIG. 4 is a schematic diagram illustrating the calculation of a score in a score calculation unit. [Figure 7] FIG. 1 is a block diagram showing an example of the hardware configuration of a computer device. DETAILED DESCRIPTION OF THE INVENTION

[0013] Prior to describing the embodiments of the present disclosure, an overview of the present disclosure will be described. FIG. 1 schematically illustrates an authentication system including an authentication device according to the present disclosure. The authentication system 10 includes an authentication device 20, an update notification device 30, and an imaging device 50. The imaging device 50 captures an image of a person to be authenticated. The authentication device 20 acquires the captured image from the imaging device 50 and authenticates the person to be authenticated. The update notification device 30 determines whether to prompt the user to update a registered image used for authentication in the authentication device 20. Note that the authentication device 20 and the update notification device 30 do not necessarily need to be configured as independent devices. For example, the update notification device 30 may be included in the authentication device 20.

[0014] The authentication device 20 has a facial image acquisition means 21 and an authentication means 22. The facial image acquisition means 21 acquires a facial image of the person to be authenticated from an image captured by the imaging device 50. The authentication means 22 compares the facial image of the person to be authenticated with a registered image of the registrant, and authenticates the person to be authenticated. In authenticating the person to be authenticated, the authentication means 22 may compare a feature extracted from the facial image of the person to be authenticated with a feature extracted from the registered image of the registrant.

[0015] The update notification device 30 includes a calculation means 31, a determination means 32, and a notification means 33. When the authentication device 20 has successfully authenticated the person to be authenticated, the calculation means 31 compares the face image of the person to be authenticated acquired by the face image acquisition means 21 with a face image of the person to be authenticated that was successfully authenticated in the past, and calculates a score indicating the degree of match. The calculation means 31 may compare a feature amount extracted from the face image with a feature amount extracted from a face image that was successfully authenticated in the past.

[0016] The determination means 32 determines whether or not to prompt the person to be authenticated to update the registered image based on the score calculated by the calculation means 31. When the determination means 32 determines to prompt the person to be authenticated to update the registered image, the notification means 33 transmits a notification to the person to be authenticated to prompt the person to update the registered image.

[0017] In facial recognition, a user's face may change over time, and this change may result in a decrease in authentication accuracy. In order to prevent a decrease in authentication accuracy, the user may periodically update the registered image. However, the user may forget to update the registered image, and in that case, the old registered image continues to be used. Furthermore, the user may find updating the registered image bothersome, and therefore it is necessary to prompt the user to update the registered image at an appropriate time.

[0018] In the present disclosure, calculation means 31 compares the facial image acquired by facial image acquisition means 21 with facial images that have been successfully authenticated in the past, and calculates a score. Based on the calculated score, determination means 32 determines whether to prompt the person to be authenticated to update the registered image, and notification means 33 sends a notification to the person to be authenticated prompting them to update the registered image. In the present disclosure, if the matching score becomes low for a facial image that has been successfully authenticated in the past, a notification is sent to the user prompting them to update the registered image.

[0019] In related technologies including Patent Document 1, the registered image is updated based on the matching score between the image of the person to be authenticated and the registered image. However, in such cases, if the shooting environment and shooting conditions differ between the registered image and the facial image actually used for authentication, facial changes may not be detected appropriately. In the present disclosure, facial images captured using an imaging device 50 are compared, and whether or not to prompt the user to update the registered image is determined based on the matching score. Therefore, the update notification device 30 can prompt the user to update the registered image at an appropriate time even if the registered image used for authentication differs from the image captured using the imaging device 50. The user can receive a notification prompting the user to update the registered image at an appropriate time, allowing them to update the registered image without feeling inconvenienced. By updating the registered image at an appropriate time, the user can continue to enjoy the security and convenience of facial authentication.

[0020] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Note that the following description and drawings have been omitted and simplified as appropriate for clarity of explanation. In addition, in the following drawings, the same or similar elements are designated by the same reference numerals, and duplicate explanations are omitted as necessary.

[0021] FIG. 2 shows an authentication system including an authentication device according to an embodiment of the present disclosure. The authentication system 100 includes an authentication device 110 and a camera 130. An example in which the authentication system 100 is used for vehicle interior entry in a vehicle such as an automobile will be described below. The authentication system 100 is not limited to vehicle interior entry, and can be applied to authentication in various systems. The authentication system 100 corresponds to the authentication system 10 shown in FIG. 1.

[0022] The camera 130 photographs a person to be authenticated (a subject). In this embodiment, the camera 130 photographs a subject outdoors. The camera 130 photographs, for example, a person about to get into a vehicle. The vehicle is a moving body such as a passenger car, a taxi, or a van. The camera 130 is mounted on the vehicle, for example, and photographs the subject outside the vehicle from inside the vehicle. The camera 130 may also be installed outside the vehicle and photograph the subject approaching the vehicle. Note that the number of cameras 130 in the authentication system 100 is not limited to one. The authentication system 100 may have multiple cameras 130. The camera 130 corresponds to the imaging device 50 shown in FIG. 1.

[0023] The authentication device 110 acquires an image of the subject from a camera 130 and performs authentication of the subject using the acquired image. The authentication device 110 is mounted on, for example, a vehicle. The authentication device 110 includes an image acquisition unit 111, a face detection unit 112, a face information DB (database) 113, a matching unit 114, a history information storage unit 115, a score calculation unit 116, a determination unit 117, and a notification unit 118. The authentication device 110 is configured as a device including, for example, one or more processors and one or more memories. At least a part of the function of each unit in the authentication device 110 can be realized by the processor performing processing in accordance with a program read from the memory. The authentication device 110 corresponds to the authentication device 20 and the update notification device 30 shown in FIG. 1.

[0024] The image acquisition unit 111 acquires video (images) captured by the camera 130. The image acquisition unit 111 sequentially acquires the latest image data captured by the camera 130. The face detection unit 112 detects a face area (face image) from the image data acquired by the image acquisition unit 111. The face detection unit 112 corresponds to the face image acquisition means 21 shown in FIG. 1.

[0025] The face information DB 113 stores face information for each of one or more users (registrants) to be authenticated. Each user registers his or her own face image in the authentication device 110. For example, each user registers a camera image taken with a smartphone or a digital camera that the user owns in the authentication device 110. The face information DB 113 stores the registered face image as a master. A face image registered by a user is also called a registered image. In addition to or instead of the registered image, the face information DB 113 may store feature amounts extracted from the registered image as a master.

[0026] It should be noted that the face information DB 113 does not necessarily have to be included in the authentication device 20. The face information DB 113 may be configured using, for example, a storage device connected to the authentication device 20 via a network.

[0027] The matching unit 114 matches the face image detected by the face detection unit 112 with the registered image registered in the face information DB 113. More specifically, the matching unit 114 acquires the registered image of each user from the face information DB 113. The matching unit 114 matches the face image detected by the face detection unit 112 with the acquired registered image of each user. The matching unit 114 extracts, for example, facial features from the face image detected by the face detection unit 112 and compares the extracted features with features extracted from the registered image.

[0028] The matching unit 114 calculates a matching score indicating the degree of match or similarity between the subject's facial image and the registered image. In the following description, it is assumed that the higher the degree of match or similarity, the higher the matching score. The matching unit 114 calculates a matching score for each of one or more users. The matching unit 114 determines whether or not face authentication has been successful based on the matching score. For example, the matching unit 114 compares the matching score calculated for each user with a threshold value, and determines whether or not face authentication has been successful based on the comparison result.

[0029] For example, if the matching score between the subject's face image and a registered image of a certain user is equal to or greater than a threshold, the matching unit 114 determines that face authentication is successful. If face authentication is successful, the matching unit 114 identifies the subject as the registered user with the highest matching score. The matching unit 114 corresponds to the authentication means 22 shown in FIG. 1.

[0030] The authentication device 110 outputs the authentication result to a device (not shown) such as an ECU (Electronic Control Unit) that controls the vehicle. If the test subject is authenticated as a pre-registered user, the ECU unlocks the vehicle door and allows the user to get into the vehicle. If the test subject is not authenticated as a pre-registered user, the ECU does not unlock the vehicle door.

[0031] The face information DB 113 stores, for each user, the face images or feature amounts of subjects whose face authentication has been successful as history information, in addition to the registered images. When face authentication is successful in the matching unit 114, the history information storage unit (history information storage means) 115 stores, in the face information DB 113, the face image or feature amounts detected by the face detection unit 112 as a face image whose face authentication has been successful in the past. For example, when the user first succeeds in authentication after the registered image for each user is registered, the history information storage unit 115 may store the face image in the face information DB 113 as a face image whose face authentication has been successful in the past. For example, the history information storage unit 115 may store, for each user, face images whose face authentication has been successful in multiple past face authentication attempts in the face information DB 113.

[0032] When the subject's face is successfully authenticated, the score calculation unit 116 compares the face image detected by the face detection unit 112 with face images of the subject that have been successfully authenticated in the past, and calculates a score indicating the degree of match. The score calculation unit 116 acquires, from the face information DB 113, face images of the subject that have been successfully authenticated in the past. For example, the score calculation unit 116 may acquire the oldest face image among multiple face images stored in the face information DB 113 as the face image that has been successfully authenticated in the past. The score calculation unit 116 compares the acquired face image with the current face image detected by the face detection unit 112. The score calculation unit 116 may compare feature amounts extracted from the face image. The score calculation unit 116 may store the calculated score in the face information DB 113. The score calculation unit 116 corresponds to the calculation means 31 shown in FIG. 1.

[0033] Fig. 3 shows an example of face information stored in the face information DB 113. In Fig. 3, a user ID (Identifier) ​​indicates an ID for identifying each user. faceThe information DB 113 stores, for each user, a registered image and face images that have been successfully authenticated in the past. The registered image may be an image captured using the camera 130, or may be an image captured using an imaging device different from the camera 130. In contrast, a face image that has been successfully authenticated in the past is an image captured by the camera 130 when the matching unit 114 determines that face authentication has been successful. The score history indicates a history of scores calculated by the score calculation unit 116 between face images that have been successfully authenticated in the past and the face image of the subject.

[0034] The history information storage unit 115 may further store, as history information, in the face information DB 113, at least one of the facial state in the face image and the shooting conditions when the face image was captured for a face image that has been successfully authenticated. The facial state may include, for example, at least one of the face orientation and whether or not a mask is worn. The shooting conditions may include at least one of the weather, date, time, and shooting location. The score calculation unit 116 may classify the face image into one of multiple groups based on at least one of the facial state in the face image and the shooting conditions. In this case, the score calculation unit 116 may acquire, from among past face images stored in the face information DB 113, face images that belong to the same group as the current face image as face images that have been successfully authenticated in the past for the person to be authenticated. In this case, face images with similar facial states and shooting conditions can be matched with each other.

[0035] The determination unit 117 determines whether to prompt the subject to update the registered image based on the score calculated by the score calculation unit 116. In other words, the determination unit 117 determines whether it is desirable to update the registered image based on the calculated score. The determination unit 117, for example, determines whether the score calculated by the score calculation unit 116 is equal to or less than a threshold value. The reason for a low score is thought to be that time has passed since the registration of the registered image and the face has changed. If the determination unit 117 determines that the calculated score is equal to or less than the threshold value, it determines that it is desirable to update the registered image.

[0036] The determination unit 117, for example, faceIt may be determined whether the score has decreased based on past scores (their history) stored in information DB 113 and the current score calculated by score calculation unit 116. For example, if the scores have shown a decreasing trend in the past multiple face authentications and the current score is less than a predetermined value, determination unit 117 determines that it is desirable to update the registered image. Determination unit 117 corresponds to determination means 32 shown in FIG. 1.

[0037] If the decision unit 117 decides that updating the registered image is desirable, the notification unit 118 sends the subject a notification urging them to update the registered image. The notification unit 118 sends the subject a message, for example, by email, urging them to update the registered image. After receiving the notification, the subject takes a picture of their own face using, for example, a smartphone. The subject can register the registered image in the face information DB 113 through registration means (not shown). The notification unit 118 corresponds to the notification means 33 shown in FIG. 1.

[0038] Next, the operation procedure will be explained. Fig. 4 shows the operation procedure in authentication device 110. Image acquisition unit 111 acquires camera images from camera 130 (step S1). Image acquisition unit 111 periodically performs step S1 and acquires camera images in time series from camera 130, which captures moving images. Face detection unit 112 detects a face area from the camera images acquired by image acquisition unit 111 (step S2). Face detection unit 112 outputs an image of the face area (face image) detected in step S2 to matching unit 114.

[0039] The matching unit 114 performs face authentication on the face image input from the face detection unit 112 (step S3). In face authentication, the matching unit 114 matches the face image input from the face detection unit 112 with each of the registered images registered in the face information DB 113. The matching unit 114 calculates a matching score between each registered image and the face image input from the face detection unit 112. The matching unit 114 determines whether or not face authentication has been successful based on the calculated matching score (step S4). In step S4, the matching unit 114 compares the calculated matching score for each registered image with a threshold value and determines whether or not the matching score is equal to or greater than the threshold value.

[0040] If the matching score is smaller than the threshold value, the matching unit 114 determines in step S4 that the face authentication has failed. In this case, the matching unit 114 outputs a message indicating that the face authentication has failed (step S5). If the face authentication has failed, the authentication device 110 may return to step S1 and perform the face authentication again from the beginning. If the matching score is equal to or greater than the threshold value, the matching unit 114 determines in step S4 that the face authentication has succeeded. In this case, the matching unit 114 outputs a message indicating that the face authentication has succeeded (step S6). In step S6, the matching unit 114 also outputs the user ID corresponding to the registered image that has the highest matching score with the face image input from the face detection unit 112.

[0041] If the face authentication is successful, the history information storage unit 115 stores the face image matched with the registered image in the face information DB 113 as a face image that has been successfully authenticated in the past (step S7). The score calculation unit 116 acquires, from the face information DB 113, face images that have been successfully authenticated in the past in face authentication. The score calculation unit 116 acquires, from the face information DB 113, face images that have been successfully authenticated in the past, corresponding to the user ID identified in face authentication. The score calculation unit 116 compares the face image detected in step S2 with the face images that have been successfully authenticated in the past and that have been acquired from the face information DB 113, and calculates a score (step S8).

[0042] The determination unit 117 compares the score calculated in step S8 with a predetermined threshold value (step S9). The threshold value used for comparison in step S9 may be the same as or different from the threshold value used in determining whether face authentication has been successful in step S4. In step S9, the determination unit 117 determines whether the calculated score is less than the threshold value. If the calculated threshold value is less than the threshold value, the determination unit 117 determines that it is desirable to update the registered image. If the calculated threshold value is equal to or greater than the threshold value, the determination unit 117 determines that it is not necessary to update the registered image.

[0043] If it is determined in step S9 that the score calculated is less than the threshold value, the notification unit 118 sends the subject a notification prompting them to update the registered image (step S10). If it is determined in step S9 that the score calculated is equal to or greater than the threshold value, the notification prompting them to update the registered image is not sent. The operations in steps S7 to S10 correspond to the operations of the registered image update notification method.

[0044] The processing flow will be explained below using a specific example. FIG. 5 schematically illustrates face authentication. In FIG. 5, the authentication target image indicates the face image of the subject detected by the face detection unit 112. The matching unit 114 matches the authentication target image with the registered image to identify the subject. Here, it is assumed that the matching unit 114 has identified the subject as the user with user ID: 001. The history information storage unit 115 stores the authentication target image for which face authentication has succeeded in this case in the face information DB 113 as history information of the user with user ID: 001. The face information DB 113 stores authentication target images for the user with user ID: 001 at each time from t=1 to t=n. It is assumed that time t=1 is the oldest time and t=n is the newest time. Time t=1 may be the time when face authentication was first performed after the registered image was registered.

[0045] 6 schematically shows an example of score calculation in the score calculation unit 116. The score calculation unit 116 selects the authentication target image at t=1, which has the oldest time, from among a plurality of past authentication target images stored in the face information DB 113, as a reference image. The score calculation unit 116 calculates a score (matching score) between the authentication target image at t=1 selected as the reference and the authentication target image at each time. The method of calculating the score in the score calculation unit 116 may be the same as the method of calculating the matching score in the matching unit 114. When a history of scores at previous times is stored in the face information DB 113, the score calculation unit 116 only needs to calculate a score between the authentication target image at t=1 and the authentication target image at t=n.

[0046] Referring to the example of FIG. 6, the score is 0.9 at time t=2, and 0.7 at time t=3. Furthermore, the score is 0.6 at t=n. In this case, although face authentication is successful as a result of matching with the registered image at t=n, a decrease in the score is observed when matching with the oldest authentication target image. For example, if the threshold value is set to 0.65, the determination unit 117 determines that updating the registered image is desirable at t=n. In this case, the notification unit 118 sends a message to the user with user ID: 001 urging them to update the registered image. The user who receives the message updates the registered image as necessary.

[0047] In this embodiment, the score calculation unit 116 compares the face image detected by the face detection unit 112 with face images that have been successfully authenticated in the past, and calculates a score. The determination unit 117 determines whether or not it is desirable to update the registered image based on the calculated score. If it is determined that it is desirable to update the registered image, the notification unit 118 transmits a notification urging the user to update the registered image. In this embodiment, it is considered that the shooting environment of the image captured by the camera 130 used for face authentication differs from that of the image captured as the registered image. In this embodiment, a notification urging the user to update the registered image is transmitted based on the score between the image and the previous authentication target image. This eliminates a decrease in score due to differences in the shooting environment, and makes it possible to prompt the user to update the registered image at an appropriate time.

[0048] In the above embodiment, the score calculation unit 116 may further compare each of the registered images with each of the authentication target images (see FIG. 5) stored in the face information DB 113 at each time and further calculate a matching score with the registered image. The determination unit 117, for example, calculates the amount of decrease in the highest matching score at each time, which is expected to be the genuineness score. A decrease in the genuineness score may indicate that the subject's face has changed from the face in the registered image. The determination unit 117 may determine that updating the registered image is desirable if the amount of decrease in the genuineness score from time t=1 to time t=n is equal to or greater than a predetermined threshold. As another example, the determination unit 117 may determine that updating the registered image is desirable if the difference between the average genuineness score and the matching score threshold for determining successful authentication is smaller than a predetermined reference value.

[0049] Alternatively, the determination unit 117 may calculate the average value of the matching scores excluding the highest matching score at each time as the other score (the average value). In this case, the determination unit 117 calculates the increase in the other score. An increase in the other score may indicate that the subject's face is beginning to resemble the face of a registered image of another person. The determination unit 117 may determine that updating the registered image is desirable if the increase in the other score from time t=1 to time t=n is equal to or greater than a predetermined threshold. As another example, the determination unit 117 may determine that updating the registered image is desirable if the difference between the other score (the average) and the matching score threshold for determining successful authentication is smaller than a predetermined reference value.

[0050] In the above embodiment, the history information storage unit 115 may determine whether to store a face image in the face information DB 113 based on the state of the face in the face image detected by the face detection unit 112. For example, if the subject's face is facing sideways, the history information storage unit 115 may not store the face image in the face information DB 113 even if face authentication is successful. If the brightness of the face image does not meet a predetermined standard, that is, if the image is dark, the history information storage unit 115 may not store the face image in the face information DB 113 even if face authentication is successful. In such cases, it is possible to prevent a decrease in the score calculated by the score calculation unit 116 due to factors other than aging of the face and to prevent a notification urging the user to update the registered image from being sent.

[0051] Next, the hardware configuration of the authentication device 110 will be described. Fig. 7 shows an example of the hardware configuration of a computer device that can be used for the authentication device 110. The computer device 500 has a processor (CPU: Central Processing Unit) 501, a ROM (read only memory) 502, and a RAM (random access memory) 503. In the computer device 500, the processor 501, the ROM 502, and the RAM 503 are connected to each other via a bus 504. The authentication device 110 may include other circuits such as peripheral circuits, communication circuits, and interface circuits, although these are not shown.

[0052] The ROM 502 is a non-volatile storage device. For example, a semiconductor storage device with a relatively small capacity, such as a flash memory, is used for the ROM 502. The ROM 502 stores the programs executed by the processor 501.

[0053] The program includes instructions (or software code) that, when loaded into a computer, cause the computer to perform one or more functions described in the embodiments. The program may be stored in a non-transitory computer-readable medium or a tangible storage medium. By way of example and not limitation, computer-readable media or tangible storage media include RAM, ROM, flash memory, solid-state drive (SSD) or other memory technologies, compact discs (CDs), digital versatile discs (DVDs), Blu-ray discs or other optical disc storage, magnetic cassettes, magnetic tapes, magnetic disk storage or other magnetic storage devices. The program may also be transmitted on a transitory computer-readable medium or a communication medium. By way of example and not limitation, transitory computer-readable media or communication media include electrical, optical, acoustic, or other forms of propagated signals.

[0054] The RAM 503 is a volatile storage device. Various semiconductor memory devices such as a dynamic random access memory (DRAM) or a static random access memory (SRAM) are used for the RAM 503. The RAM 503 can be used as an internal buffer for temporarily storing data and the like.

[0055] The processor 501 loads the program stored in the ROM 502 into the RAM 503 and executes the program. When the CPU 501 executes the program, the functions of the various units in the authentication device 110 can be realized.

[0056] In the above embodiment, the authentication device 110 does not necessarily have to be a single device. The authentication device 110 may be configured using multiple physically separated devices. Furthermore, when the authentication device 110 is used for vehicle interior entry, not all functions of the authentication device 110 necessarily need to be installed in the vehicle. For example, each unit of the authentication device 110 may be located outside the vehicle. In this case, the authentication device 110 may acquire camera images from the camera 130 via a wireless communication network. The authentication device 110 may transmit authentication results to the vehicle via the wireless communication network.

[0057] Although the embodiments of the present disclosure have been described in detail above, the present disclosure is not limited to the above-described embodiments, and changes and modifications to the above-described embodiments that do not deviate from the spirit of the present disclosure are also included in the present disclosure.

[0058] For example, some or all of the above embodiments can be described as, but are not limited to, the following supplementary notes.

[0059] [Appendix 1] a calculation means for, when authentication of a face image of a person to be authenticated included in an image captured by an imaging device is successful, comparing the face image of the person to be authenticated or a feature amount extracted from the face image with a face image or the feature amount of the person to be authenticated when the person to be authenticated was successfully authenticated in the past, and calculating a score indicating the degree of match; a decision means for deciding whether to prompt the person to be authenticated to update the registered image used for the authentication based on the score; an update notification device including a notification means for transmitting a notification to the authentication subject prompting the authentication subject to update the registered image when it is determined that the registered image should be updated;

[0060] [Appendix 2] The update notification device described in Appendix 1, wherein the decision means determines whether the score is below a threshold value, and if it determines that the score is below the threshold value, decides to prompt the person to be authenticated to update the registered image.

[0061] [Appendix 3] further comprising a history information storage means for storing, when the person to be authenticated is successfully authenticated, at least one of the facial image and the feature amount and the score as history information; 3. The update notification device according to claim 1, wherein the calculation means acquires, from the history information, a facial image or the feature amount of the person to be authenticated when the person to be authenticated was authenticated in the past.

[0062] [Appendix 4] the history information includes a plurality of face images or the feature amounts, The update notification device described in Appendix 3, wherein the calculation means acquires from the history information the oldest facial image or feature value among the plurality of facial images or feature values ​​included in the history information as the facial image or feature value of the person to be authenticated when the authentication was successful in the past.

[0063] [Appendix 5] The update notification device according to claim 3 or 4, wherein the calculation means classifies the facial image into one of a plurality of groups based on at least one of the facial state in the facial image and the shooting conditions when the facial image was shot, and acquires, from at least one of the facial images and the features included in the history information, the facial image or the feature that belongs to the same group as the group to which the facial image belongs, as the facial image or the feature when the person to be authenticated was successfully authenticated in the past.

[0064] [Appendix 6] 6. The update notification device according to claim 5, wherein the history information storage means further stores at least one of the facial state in the facial image and the photographing conditions when the facial image was photographed as the history information.

[0065] [Appendix 7] 7. The update notification device according to claim 5, wherein the face state includes at least one of the face direction and whether or not the face is wearing a mask.

[0066] [Appendix 8] 8. The update notification device according to any one of appendices 5 to 7, wherein the photography conditions include at least one of weather, date and time, and photography location.

[0067] [Appendix 9] the history information storage means further stores the score as the history information; The update notification device according to any one of appendices 3 to 8, wherein the determination means determines whether the score has decreased based on the score included in the history information and the score calculated by the calculation means, and if it determines that the score has decreased, determines to prompt the person to be authenticated to register the registration image.

[0068] [Appendix 10] The update notification device described in any one of Supplementary Notes 3 to 9, wherein the history information storage means determines whether to store at least one of the facial image and the feature amount as the history information based on the state of the face in the facial image.

[0069] [Appendix 11] a facial image acquisition means for acquiring a facial image of the person to be authenticated from a captured image acquired by an imaging device that captures an image of the person to be authenticated; an authentication means for comparing the acquired face image of the person to be authenticated or the feature amount extracted from the face image with a registered image of a registrant or the feature amount extracted from the registered image, and authenticating the person to be authenticated; a calculation means for comparing the acquired facial image or the feature amount of the person to be authenticated with a facial image or the feature amount of the person to be authenticated when the person to be authenticated has been successfully authenticated in the past, and calculating a score indicating the degree of match; a decision means for deciding whether to prompt the person to be authenticated to update the registered image based on the score; an authentication device comprising: a notification means for transmitting a notification to the authentication subject prompting the authentication subject to update the registered image when it is determined that the authentication subject should update the registered image;

[0070] [Appendix 12] The authentication device described in Appendix 11, wherein the decision means determines whether the score is below a threshold value, and if it determines that the score is below the threshold value, decides to prompt the person to be authenticated to update the registered image.

[0071] [Appendix 13] further comprising a history information storage means for storing, when the person to be authenticated is successfully authenticated, at least one of the facial image and the feature amount and the score as history information; 13. The authentication device according to claim 11, wherein the calculation means acquires, from the history information, a facial image or the feature amount when the person to be authenticated was authenticated in the past.

[0072] [Appendix 14] If authentication of a face image of the person to be authenticated included in an image captured using an imaging device is successful, the face image of the person to be authenticated or a feature amount extracted from the face image is compared with a face image or a feature amount of the person to be authenticated when the person to be authenticated was successfully authenticated in the past, and a score indicating the degree of match is calculated; determining whether to prompt the person to be authenticated to update the registered image used for the authentication based on the score; an update notification method including, when it is determined that the registered image should be updated, sending a notification to the person to be authenticated that prompts the person to update the registered image;

[0073] [Appendix 15] If authentication of a face image of the person to be authenticated included in an image captured using an imaging device is successful, the face image of the person to be authenticated or a feature amount extracted from the face image is compared with a face image or a feature amount of the person to be authenticated when the person to be authenticated was successfully authenticated in the past, and a score indicating the degree of match is calculated; determining whether to prompt the person to be authenticated to update the registered image used for the authentication based on the score; A non-transitory computer-readable medium storing a program for causing a computer to execute a process including sending a notification to the authentication subject prompting the person to update the enrollment image if it is determined that the person should update the enrollment image. [Explanation of symbols]

[0074] 10: Authentication system 20: Authentication device 21: Facial image acquisition means 22: Authentication method 30: Update notification device 31: Calculation method 32:Decision making method 33: Notification means 50: Imaging device 100: Authentication system 110: Authentication device 111: Image acquisition unit 112: Face detection unit 113:Facial information DB 114: Matching section 115: History information storage unit 116: Score calculation section 117: Decision section 118: Notification Department 130: Camera 501: Processor 502:ROM 503:RAM 504: Bus

Claims

1. a calculation means for, when authentication of a face image of a person to be authenticated included in an image captured by an imaging device is successful, comparing the face image of the person to be authenticated or a feature amount extracted from the face image with a face image or the feature amount of the person to be authenticated when the person to be authenticated was successfully authenticated in the past, and calculating a score indicating the degree of match; a decision means for deciding whether to prompt the person to be authenticated to update the registered image used for the authentication based on the score; an update notification device including a notification means for transmitting a notification to the authentication subject prompting the authentication subject to update the registered image when it is determined that the registered image should be updated;

2. 2. The update notification device according to claim 1, wherein the decision means determines whether the score is equal to or less than a threshold value, and if it determines that the score is equal to or less than the threshold value, decides to prompt the person to be authenticated to update the registered image.

3. further comprising a history information storage means for storing, when the person to be authenticated is successfully authenticated, at least one of the facial image and the feature amount and the score as history information; 3. The update notification device according to claim 1, wherein the calculation means acquires, from the history information, a face image or the feature amount of the person to be authenticated when the person to be authenticated was authenticated in the past.

4. the history information includes a plurality of face images or the feature amounts, 4. The update notification device according to claim 3, wherein the calculation means acquires from the history information the oldest facial image or feature value among the plurality of facial images or feature values ​​included in the history information as the facial image or feature value when the person to be authenticated was successfully authenticated in the past.

5. 5. The update notification device according to claim 3, wherein the calculation means classifies the facial image into one of a plurality of groups based on at least one of the facial state in the facial image and the shooting conditions when the facial image was shot, and acquires, from at least one of the facial images and the feature amounts included in the history information, the facial image or the feature amount that belongs to the same group as the group to which the facial image belongs, as the facial image or the feature amount when the person to be authenticated was successfully authenticated in the past.

6. 6. The update notification device according to claim 5, wherein the history information storage means further stores at least one of the facial state in the facial image and the photographing conditions when the facial image was photographed as the history information.

7. the history information storage means further stores the score as the history information; The update notification device described in any one of claims 3 to 6, wherein the decision means determines whether the score has decreased based on the score included in the history information and the score calculated by the calculation means, and if it determines that the score has decreased, decides to prompt the person to be authenticated to register the registration image.

8. a facial image acquisition means for acquiring a facial image of the person to be authenticated from a captured image acquired by an imaging device that captures an image of the person to be authenticated; an authentication means for comparing the acquired face image of the person to be authenticated or the feature amount extracted from the face image with a registered image of a registrant or the feature amount extracted from the registered image, and authenticating the person to be authenticated; a calculation means for comparing the acquired facial image or the feature amount of the person to be authenticated with a facial image or the feature amount of the person to be authenticated when the person to be authenticated has been successfully authenticated in the past, and calculating a score indicating the degree of match; a decision means for deciding whether to prompt the person to be authenticated to update the registered image based on the score; an authentication device comprising: a notification means for transmitting a notification to the authentication subject prompting the authentication subject to update the registered image when it is determined that the authentication subject should update the registered image;

9. If authentication of a face image of the person to be authenticated included in an image captured using an imaging device is successful, the face image of the person to be authenticated or a feature amount extracted from the face image is compared with a face image or a feature amount of the person to be authenticated when the person to be authenticated was successfully authenticated in the past, and a score indicating the degree of match is calculated; determining whether to prompt the person to be authenticated to update the registered image used for the authentication based on the score; an update notification method including, when it is determined that the registered image should be updated, sending a notification to the person to be authenticated that prompts the person to update the registered image;

10. If authentication of a face image of the person to be authenticated included in an image captured using an imaging device is successful, the face image of the person to be authenticated or a feature amount extracted from the face image is compared with a face image or a feature amount of the person to be authenticated when the person to be authenticated was successfully authenticated in the past, and a score indicating the degree of match is calculated; determining whether to prompt the person to be authenticated to update the registered image used for the authentication based on the score; a program for causing a computer to execute a process including, when it is determined that the user is to be prompted to update the registered image, sending a notification to the user to be authenticated that prompts the user to update the registered image;

Images