Authentication system, authentication device, authentication method, and program

Abstract

To provide an authentication system configured to reduce the time required for iris authentication, an authentication apparatus, an authentication method, and a program.SOLUTION: An authentication apparatus 100 includes: an iris relevant part extraction unit 152 which extracts iris relevant part data which corresponds to iris from captured image data; an availability determination unit 153 which determines whether the iris relevant part data can be used for iris authentication or not, on the basis of a ratio of the area of an iris relevant part corresponding to the iris relevant part data extracted by the iris relevant part extraction unit 152 with respect to the area of an iris relevant part corresponding to criterion iris data; an iris data generation unit 154 which generates, after determining that the iris relevant part data can be used for the iris authentication, authentication iris data in a predetermined format by use of the iris relevant part data; and an authentication processing unit 155 which compares the authentication iris data with reference iris data stored in advance as iris data for reference in authentication processing, to execute the authentication processing.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] A technique for performing authentication (iris authentication) by comparing an image of an eye taken with feature information of an iris is known (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In imaging an eye for iris authentication, it may not be possible to obtain an eye image of sufficient quality for use in iris authentication. In this case, after imaging the eye again, the processing up to iris authentication is performed again, which takes unnecessary time.

[0005] The present invention has been made in view of such circumstances, and an object thereof is to shorten the time required for iris authentication.

Means for Solving the Problems

[0006] One aspect of the present invention for solving the above-mentioned problems is an iris-corresponding portion extraction unit that extracts iris-corresponding portion data corresponding to the iris from captured image data obtained by imaging; a usability determination unit that determines whether the iris-corresponding portion data can be used for iris authentication based on the ratio of the area of ​​the iris-corresponding portion data extracted by the iris-corresponding portion extraction unit to the area of ​​the iris-corresponding portion corresponding to the iris-corresponding portion of reference iris data; an iris data generation unit that generates authentication target iris data in a predetermined format using the iris-corresponding portion data after the usability determination unit has determined that the iris-corresponding portion data can be used for iris authentication; and an authentication processing unit that performs authentication processing by comparing the authentication target iris data with reference iris data stored in advance as reference iris data for the authentication process. The system includes the following functions: In response to the registration of the reference iris data, the iris portion extraction unit extracts iris portion data from the captured image data; the usability determination unit determines whether the extracted iris portion data is usable as reference iris data based on the ratio of the area of ​​the iris portion corresponding to the extracted iris portion data to the total area of ​​the iris calculated based on the captured image data; and the iris data generation unit generates reference iris data, which is iris data showing feature quantities, using the iris portion data that the usability determination unit has determined to be usable. It is an authentication system.

[0007] One aspect of the present invention includes: an iris portion extraction unit that extracts iris portion data corresponding to the iris from captured image data obtained by imaging; a usability determination unit that determines whether the iris portion data can be used for iris authentication based on the ratio of the area of ​​the iris portion data extracted by the iris portion extraction unit to the area of ​​the iris portion corresponding to the iris portion corresponding to the reference iris data; an iris data generation unit that generates authentication target iris data in a predetermined format using the iris portion data after the usability determination unit has determined that the iris portion data can be used for iris authentication; and an authentication processing unit that performs authentication processing by comparing the authentication target iris data with reference iris data stored in advance as reference iris data for the authentication process. The system includes the following functions: In response to the registration of the reference iris data, the iris portion extraction unit extracts iris portion data from the captured image data; the usability determination unit determines whether the extracted iris portion data is usable as reference iris data based on the ratio of the area of ​​the iris portion corresponding to the extracted iris portion data to the total area of ​​the iris calculated based on the captured image data; and the iris data generation unit generates reference iris data, which is iris data showing feature quantities, using the iris portion data that the usability determination unit has determined to be usable. It is an authentication device.

[0008] One aspect of the present invention includes: an iris portion extraction step of extracting iris portion data corresponding to the iris from captured image data obtained by imaging; a usability determination step of determining whether the iris portion data can be used for iris authentication based on the ratio of the area of ​​the iris portion data extracted in the iris portion extraction step to the area of ​​the iris portion corresponding to the iris portion corresponding to the reference iris data; an iris data generation step of generating authentication target iris data in a predetermined format using the iris portion data after it has been determined in the usability determination step that the iris portion data can be used for iris authentication; and an authentication processing step of performing an authentication process by comparing the authentication target iris data with reference iris data stored in advance as reference iris data for the authentication process. The process includes, in response to the registration of the reference iris data, the iris portion extraction step extracts iris portion data from the captured image data, the usability determination step determines whether the extracted iris portion data is usable as reference iris data based on the ratio of the area of ​​the iris portion corresponding to the extracted iris portion data to the total area of ​​the iris calculated based on the captured image data, and the iris data generation step generates reference iris data, which is iris data showing feature quantities, using the iris portion data that was determined to be usable in the usability determination step. This is an authentication method.

[0009] One aspect of the present invention relates to a computer as an authentication device, comprising: an iris portion extraction unit that extracts iris portion data corresponding to the iris from captured image data obtained by imaging; a usability determination unit that determines whether the iris portion data can be used for iris authentication based on the ratio of the area of ​​the iris portion data extracted by the iris portion extraction unit to the area of ​​the iris portion corresponding to the iris portion corresponding to the reference iris data; an iris data generation unit that generates authentication target iris data in a predetermined format using the iris portion data after the usability determination unit has determined that the iris portion data can be used for iris authentication; and a program for causing a computer as an authentication device to function as an authentication processing unit that performs authentication processing by comparing the authentication target iris data with reference iris data stored in advance as reference iris data for the authentication process. The program is configured such that, in response to the registration of the reference iris data, the iris portion extraction unit extracts iris portion data from the captured image data, the usability determination unit determines whether the extracted iris portion data is usable as reference iris data based on the ratio of the area of ​​the iris portion to which the extracted iris portion data corresponds to the total area of ​​the iris calculated based on the captured image data, and the iris data generation unit generates reference iris data, which is iris data showing feature quantities, using the iris portion data that the usability determination unit has determined to be usable. That is the case. [Effects of the Invention]

[0010] As described above, the present invention has the effect of reducing the time required for iris recognition. [Brief explanation of the drawing]

[0011] [Figure 1] This figure shows an example configuration of the authentication device according to this embodiment. [Figure 2] This flowchart shows an example of the processing procedure performed by the authentication device according to this embodiment in connection with the registration of reference iris data. [Figure 3] This figure schematically illustrates an example of the procedure for registering and authenticating reference iris data according to this embodiment. [Figure 4] This flowchart shows an example of the processing procedure that the authentication device according to this embodiment performs in relation to the authentication process. [Figure 5] This figure shows an example of notification by display in the authentication device according to this embodiment. [Modes for carrying out the invention]

[0012] [Example of Authentication Device Configuration] Figure 1 shows an example configuration of the authentication device 100 of this embodiment. The authentication device 100 of this embodiment is capable of using iris authentication for user authentication to unlock the device and log in. The authentication device 100 in this embodiment may be, for example, a smartphone, a tablet terminal, a personal computer, etc. Furthermore, the configuration of the authentication device 100 in this embodiment may be used for user authentication when entering a designated place or room in various facilities. In the following description, the authentication device 100 in this embodiment will be given as an example of a terminal such as a smartphone.

[0013] The authentication device 100 in Figure 1 comprises a communication unit 101, an imaging unit 102, a display unit 103, an audio output unit 103A, an operation unit 104, a control unit 105, and a storage unit 106. The communications unit 101 communicates via the network. The imaging unit 102 is equipped with a camera and performs imaging to obtain image data. The display unit 103 displays information according to the control of the control unit 105. The sound output unit 103A outputs sound (electronic sound, voice) according to the control of the control unit 105. The operation unit 104 includes an input device provided (or connected) to the authentication device 100, receives an operation performed on the input device, and outputs information on the received operation to the control unit 105. Note that the operation unit 104 may have a function as the display unit 103 and be provided with a touch panel capable of receiving an operation on the display surface.

[0014] The control unit 105 executes various controls in the authentication device 100. The control unit 105 includes an eye movement determination unit 151, an iris corresponding part extraction unit 152, an availability determination unit 153, an iris data generation unit 154, an authentication processing unit 155, and a user interface control unit 156.

[0015] The eye movement determination unit 151 uses the eye image captured by the imaging unit 102 to determine whether the imaged eye is performing an eye movement. The eye movement determination unit 151, for example, controls the imaging unit 102 to capture a time-lapse image or video over a certain period, and obtains imaging image data in the form of the time-lapse image or video obtained by imaging. The eye movement determination unit 151 may determine the presence or absence of eye movement by comparing the change in the movement of the eyeball in the eyes between the images obtained by imaging with the change in the eyeball characteristic of eye movement.

[0016] Also, the eye movement determination unit 151 may determine the presence or absence of eye movement using a learned model. Such a learned model may be constructed, for example, by training a learning device using learning data (teacher data) in which various eye movement images and the correct eye movement are set as a set.

[0017] For example, when a person's eye as a living body is in a state of looking at something, eye movement occurs accordingly. In contrast, for example, an eye in a photograph or a painting that is not a living body does not cause eye movement. Therefore, the determination of the presence or absence of eye movement by the eye movement determination unit 151 corresponds to determining whether the subject eye is that of a living person or not that of a living person such as a photograph or the like.

[0018] Examples of eye movement include saccadic eye movement (saccade), smooth pursuit eye movement (SPM), convergence / divergence movement, and the like. The eye movement to be determined by the eye movement determination unit 151 of the present embodiment may be, for example, any one or more of the above.

[0019] The iris corresponding part extraction unit 152 extracts a part corresponding to the iris (iris corresponding part) from the eye image obtained by imaging by the imaging unit 102.

[0020] [[ID=!3]] The usability determination unit 153 determines whether the iris corresponding part data of the authentication target extracted by the iris corresponding part extraction unit 152 is available for iris authentication. Specifically, the usability determination unit 153 may determine whether it is available based on whether the area of the iris corresponding part in the iris corresponding part data of the authentication target is a certain ratio or more with respect to the area of the iris corresponding part corresponding to the reference iris data.

[0021] Also, the usability determination unit 153 may determine whether the iris corresponding part data extracted by the iris corresponding part extraction unit 152 corresponding to the registration of the reference iris data is available as the reference iris data.

[0022] The iris data generation unit 154 (an example of an iris data generation unit for authentication) generates iris data for authentication using the image of the iris portion to be authenticated, which is extracted by the iris portion extraction unit 152. The iris data generation unit 154 may determine the feature quantities of the extracted image of the iris portion and generate data representing the determined feature quantities as iris data for authentication. Furthermore, when generating reference iris data, the iris data generation unit 154 generates reference iris data using the image of the iris portion extracted by the iris portion extraction unit 152.

[0023] The authentication processing unit 155 performs authentication processing corresponding to iris authentication. Specifically, as part of the authentication processing, the authentication processing unit 155 may determine whether the authentication is successful or not based on the result of comparing (matching) the iris data to be authenticated generated by the iris data generation unit 154 with the reference iris data stored in the reference iris data storage unit 161. Furthermore, the authentication processing unit 155 may execute control to release the locked state of the authentication device 100 in response to determining that authentication has been successful.

[0024] The iris data generation unit 154 generates reference iris data. The reference iris data is used as a reference during iris authentication. The user is instructed to register reference iris data corresponding to their own iris with the authentication device 100 by having their eye imaged by the imaging unit 102 in advance. The iris data generation unit 154 generates reference iris data using the image of the iris portion extracted by the iris portion extraction unit 152 in response to the registration of reference iris data. The iris data generation unit 154 stores the generated reference iris data in the reference iris data storage unit 161 of the storage unit 106. By storing the reference iris data in the reference iris data storage unit 161 in this way, the registration of the reference iris data is completed.

[0025] The user interface control unit 156 performs control related to the user interface, including display control of the display unit 103, control of sound output from the sound output unit 103A, and control of the lock state. The user interface control unit 156 provides notifications to the user in accordance with predetermined situations that occur when registering reference iris data or performing iris authentication operations. The user interface control unit 156 can provide notifications by displaying information on the display unit 103 and by outputting sound from the sound output unit 103A.

[0026] The storage unit 106 stores the information corresponding to the authentication device 100. The storage unit 106 includes a reference iris data storage unit 161. The reference iris data storage unit 161 stores the reference iris data generated by the iris data generation unit 154.

[0027] [Example of processing procedure based on the registration of reference iris data] As described above, in order to enable iris authentication with the authentication device 100 of this embodiment, the user registers reference iris data with the authentication device 100. Therefore, referring to the flowchart in Figure 2, an example of the processing procedure performed by the authentication device 100 in relation to the registration of reference iris data will be described. In parallel with the explanation of Figure 2, a specific example of the image processing shown by steps 1 to 4 in Figure 3 will also be explained. Figure 3 schematically shows an example of the procedure for registering reference iris data and authentication processing in this embodiment.

[0028] Step S100: In order to register reference iris data, the user performs an operation to set the reference iris data registration mode on the authentication device 100. In response to the setting of the reference iris data registration mode, the iris portion extraction unit 152 of the authentication device 100 activates the imaging unit 102. The iris portion extraction unit 152 acquires the image data obtained by the activated imaging unit 102. Depending on step S100, an image of the eye portion (eye portion image D11) is obtained in the captured image data, as shown as step 1 in Figure 3. The eye portion image D11 includes the iris (ir) and pupil (pp). The iris (ir) may not be fully visible depending on the degree of eye opening and individual differences, and as shown in the figure, there may be parts that are obscured by the upper and lower eyelids.

[0029] Step S102: The iris portion extraction unit 152 extracts iris portion data corresponding to the image portion corresponding to the iris from the image data acquired in step S100. In the extraction process, the iris portion extraction unit 152 may detect the boundary between the pupil pp and the white of the eye relative to the iris ir by edge detection. Figure 3 shows an example where the iris ir portion of the eye image D11 is extracted as the corresponding iris data Dir1, as shown in step 2.

[0030] Note that the iris portion data Dir1 may be, for example, image data of the region including the iris ir and the pupil pp inside the iris ir.

[0031] Step S104: The availability determination unit 153 calculates the total iris area St using the eye portion image D11. The total iris area St is the area of ​​the entire iris ir, including the portion of the iris ir that is not obscured by the upper and lower eyelids in the eye portion image D11 of Figure 3, as well as the portion of the iris ir that is obscured by the upper and lower eyelids. The usability determination unit 153 can, for example, measure the radius of the iris ir that is not obscured by the upper and lower eyelids in the eye portion image D11, and calculate the total iris area St based on the measured radius. Furthermore, even if the iris ir is elliptical in shape as a whole, the total iris area St can be calculated by determining the minor and major radii based on the curvature of the outer frame of the iris ir.

[0032] Step S106: The availability determination unit 153 calculates the actual iris area So. The actual iris area So is the area of ​​the iris ir that is not obscured by the upper and lower eyelids in the eye portion image D11 of Figure 3.

[0033] Step S108: The availability determination unit 153 determines whether the iris portion data having the actual iris area So is available as reference iris data. To this end, the availability determination unit 153 determines whether the following equation 1 is satisfied. So>St×k1···(Equation 1) k1 is a coefficient. For example, the coefficient k1 is approximately 0.9 (90%). If the coefficient k1 is 0.9, the usability determination unit 153 determines that the reference iris data can be used if the actual iris area So is greater than 90% of the total iris area St. On the other hand, the usability determination unit 153 determines that the reference iris data cannot be used if the actual iris area So is 90% or less of the total iris area St. If the ratio of the area of ​​the iris portion data to the total area of ​​the iris is small, the reliability of the reference iris data will also decrease, making it difficult to obtain matching results with the accuracy required for authentication. Step S108 determines whether the ratio of the area of ​​the reference iris portion data to the total area of ​​the iris is sufficient to obtain the required accuracy for the matching process.

[0034] Step S110: If it is determined that the data is unusable as reference iris data, the user interface control unit 156 will notify the user of an error indicating that the image data obtained from this imaging is unusable as reference iris data. The error notification may be displayed on the display unit 103 with a message indicating that the data is unusable as reference iris data. In addition to the message indicating that the data is unusable as reference iris data, the display unit 103 may also display a message instructing the user to retry imaging the eye. Furthermore, error notification may be provided by outputting a message via voice. After step S110, the process returns to step S100, allowing the user to re-image the eye.

[0035] Step S112: If it is determined in step S108 that the data can be used as reference iris data, the iris data generation unit 154 normalizes the data of the corresponding part of the iris. Figure 3 shows an example where the iris portion data Dir1 is normalized to generate normalized data D12, as shown in step 3. The normalized data D12 in the figure is obtained by converting the circular iris portion data Dir1 into rectangular image data, for example, through coordinate transformation.

[0036] Step S114: The iris data generation unit 154 extracts features from the normalized data D12 obtained in step S112. Step S116: The iris data generation unit 154 generates reference iris data, which is iris data (Iris code) based on the features extracted in step S114. Figure 3 shows an example where reference iris data D13, which represents the features extracted from the normalized data D12, is generated, as shown in step 4.

[0037] Step S118: The iris data generation unit 154 stores the reference iris data D13 generated in step S116 in the reference iris data storage unit 161. At this time, the iris data generation unit 154 may also store the actual iris area So calculated in the final step S106 in the reference iris data storage unit 161 along with the reference iris data D13. The actual iris area So stored in this way represents the area of ​​the iris ir corresponding to the reference iris data.

[0038] In this way, the reference iris data is stored in the reference iris data storage unit 161, which means that the reference iris data has been registered, and thereafter, iris authentication by the authentication device 100 becomes possible.

[0039] Next, with reference to the flowchart in Figure 4, an example of the processing procedure performed by the authentication device 100 in relation to iris authentication will be described. In this embodiment, the authentication device 100 is capable of performing login authentication by selecting either iris authentication or password authentication by entering a password. Therefore, Figure 4 shows an example of the processing procedure when the authentication device 100 is in a locked state, and the user is presented with the option of iris authentication or password authentication as the authentication method for login authentication, and iris authentication is selected. In parallel with the explanation of Figure 4, we will also explain specific examples of image processing shown in steps 5 to 8 of Figure 3, as well as the screen transitions shown in Figure 5.

[0040] Step S200: In the authentication device 100, the authentication method selection screen is displayed on the display unit 103 in response to a predetermined operation being performed while the device is locked. On the authentication method selection screen, although not shown in the diagram, the options for login authentication are presented as iris recognition and password recognition. The options for iris recognition and password recognition may be placed on the authentication method selection screen as buttons that allow the user to select the corresponding authentication method.

[0041] Step S202: The user performs an operation (authentication method selection operation) to select either iris authentication or password authentication on the authentication method selection screen. The operation unit 104 receives the authentication method selection operation performed by the user.

[0042] Step S204: The control unit 105 determines whether iris authentication has been selected based on the authentication method selection operation received by the operation unit 104 in step S202.

[0043] Step S206: If it is determined in step S204 that iris authentication has been selected, the iris corresponding portion extraction unit 152 (or eye movement determination unit 151) activates the imaging unit 102. Step S208: The iris portion extraction unit 152 acquires image data obtained by the imaging unit 102, which was activated in step S206, over a certain period of time. At this time, the iris portion extraction unit 152 may cause the imaging unit 102 to capture a time-lapse image or video corresponding to the certain period of time.

[0044] Step S210: The eye movement determination unit 151 uses the captured image data acquired in step S208 to detect eye movements of the eye in the captured image data. The eye movement determination unit 151 determines whether or not eye movements have been detected for the eye in the captured image data. Eye movements can vary from person to person. Therefore, the eye movement determination unit 151 may use a trained model, which has been trained by inputting diverse characteristics of eye movements as training data, as an auxiliary means for iris authentication, to detect eye movements.

[0045] Step S212: If it is determined in step S210 that no eye movement occurred, the user interface control unit 156 will notify the user of an error regarding the failure to detect eye movement.

[0046] Figure 5(A) shows an example of how an error notification regarding the failure to detect eye movement is displayed on the notification screen of the display unit 103. The figure shows an example where a message is displayed on the notification screen informing the user that eye movement was not detected and that they should actively change their viewpoint and re-image their eyes to make eye movement easier to detect. For example, the notification screen in the figure may be cleared in response to a predetermined operation, such as a tap on the display surface. The error notification in step S212 may be performed by sound (electronic sound or voice).

[0047] After the processing in step S212, the process returns to step S206. This restarts the imaging unit 102, allowing the user to re-image the eye.

[0048] Step S214: If eye movement is detected in step S210, the user interface control unit 156 notifies the user that eye movement has been detected.

[0049] Figure 5(B) shows an example of a case in which notification of detected eye movement is provided as a notification screen on the display unit 103. The figure shows an example where a message is displayed on the notification screen informing the user that eye movement has been detected and that iris authentication processing will be performed thereafter. For example, the notification screen in the figure may be cleared in response to a predetermined operation, such as a tap on the display surface. The error notification in step S214 may also be performed by sound (electronic sound or voice).

[0050] Step S216: After processing in step S214, the iris portion extraction unit 152 extracts iris portion data corresponding to the image portion corresponding to the iris from the image image data acquired in step S208. In this process, the iris portion extraction unit 152 selects (filters) image data that meets the quality requirements for use in iris authentication from among multiple time-lapse images (or frame images of a moving image) obtained by imaging over a certain period of time in step S208. The iris portion extraction unit 152 then extracts iris portion data from the selected image data.

[0051] Figure 3 shows that, as shown in step 5, the captured image data was selected in step S216, resulting in the acquisition of a partial eye image D21 (an example of the eye portion) from the selected captured image data. Here, in the partial eye image D21, it is shown that the area of ​​the iris (ir) that is not obscured by the eyelid is smaller than in partial eye image D11 because the user did not open their eyelid sufficiently during imaging. Then, as shown in step S216, the portion of the iris (ir) that is not obscured by the eyelid is extracted as the iris portion data Dir2, as shown in step 6 of Figure 3.

[0052] Step S218: Next, the availability determination unit 153 calculates the iris area S to be authenticated. The iris area S to be authenticated is the area of ​​the iris portion data Dir2 extracted in step S216. The availability determination unit 153 may calculate the iris area S to be authenticated by the same process as in step S106 in Figure 2.

[0053] Step S220: The availability determination unit 153 determines whether the iris portion data extracted in step S216 is available for use as a matching process target in iris authentication. To this end, the availability determination unit 153 determines whether the following equation 2 is satisfied. S>So×k2...(Formula 2) k2 is a coefficient. For example, the coefficient k2 can be around 0.5 (50%). The actual iris area So is the area of ​​the corresponding portion of the iris in the reference iris data. The availability determination unit 153 may calculate the actual iris area So used in Equation 2 using the reference iris data stored in the reference iris data storage unit 161. Alternatively, if the actual iris area So is stored in the reference iris data storage unit 161 along with the reference iris data in step S118 of Figure 2, the availability determination unit 153 may use the actual iris area So stored in the reference iris data storage unit 161. Specifically, if the coefficient k2 is 0.5, the usability determination unit 153 determines that if the iris area S to be authenticated is greater than 50% of the actual iris area So, it can be used as a target for iris authentication matching. On the other hand, the usability determination unit 153 determines that if the iris area S to be authenticated is less than 50% of the actual iris area So, it cannot be used as a matching method for iris authentication.

[0054] If the ratio of the area of ​​the iris data to be authenticated to the area of ​​the iris corresponding to the reference iris data (actual iris area So) is small, it becomes difficult to obtain a matching process result with the accuracy required for authentication. Step S202 determines whether the ratio of the area of ​​the iris data to the area of ​​the iris data to be matched is sufficient to obtain the required accuracy of the matching process.

[0055] In step S220, the usability determination unit 153 may determine whether the matching process is usable based on whether the following equation 3, which uses the total iris area St instead of the actual iris area So in equation 2, is satisfied. S>St×k3...(Formula 3) The coefficient k3 in Equation 3 may be set to a different value from the coefficient k2 in Equation 2.

[0056] If it is determined in step S220 that the item is unavailable for verification, the process in step S212 is executed. If the user proceeds from step S220 to step S212, the user interface control unit 156 will notify the user of an error indicating that the image data obtained from the current imaging is unusable for authentication. The error notification may be displayed on the display unit 103 with a message indicating that the image data obtained from the current imaging is unusable for authentication. In addition to the message that the image data is unusable for authentication, the display unit 103 may also display a message instructing the user to retry imaging the eye. As a specific example, Figure 5(C) shows an example of a notification screen displayed on the display unit 103 when it is determined in step S220 that the object is unusable for the matching process. In this figure, for example, the message "Insufficient area of ​​the iris could not be obtained. Please open your eyes wide and try again." is displayed. Furthermore, error notification may be provided by outputting a message via voice.

[0057] Step S222: If it is determined in step S22 that the data is available for matching, the iris data generation unit 154 normalizes the iris data extracted in step S216. Figure 3 shows an example in which the iris portion data Dir2 is normalized to generate normalized data D22, as shown in step 7. As shown in the figure, normalized data D22 corresponds to a portion of the normalized data D12 that formed the basis of the reference iris data D13.

[0058] Step S224: The iris data generation unit 154 extracts features from the normalized data D22 obtained in step S222. Step S226: The iris data generation unit 154 generates matching iris data using the feature quantities extracted in step S224. Figure 3 shows an example where matching iris data D23, which represents the features extracted from the normalized data D22, is generated, as shown in step 8. Matching iris data D23 also corresponds to a portion of the reference iris data D13.

[0059] Step S228: The authentication processing unit 155 acquires reference iris data from the reference iris data storage unit 161. Step S230: The authentication processing unit 155 performs a matching process to compare the iris data to be matched generated in step S226 with the reference iris data obtained in step S228. The process in step S230 is shown as step 9 in Figure 3. The authentication processing unit 155 compares the iris data to be matched D23 with the corresponding region in the reference iris data D13. Regarding the matching process described above, the authentication processing unit 155 may use the Hamming distance and, for example, an XOR circuit to determine the matching result by assigning "0" to codes that were matched (matched) between the iris data D23 to be matched and the reference iris data D13, and "1" to codes that were not matched (did not match), and then using the ratio of the number of "1"s (Hamming distance) to the total. Furthermore, the authentication processing unit 155 may perform the matching process by determining whether the iris data (Iris code) features matched using the matching results of the matching of the iris data D23 and the reference iris data D13, instead of determining whether the iris data matches or does not match using the Hamming distance. In this case, the trained model may be any of the following: a classifier such as a support vector machine, classical machine learning, quantum machine learning, or deep learning.

[0060] Step S232: The authentication processing unit 155 determines, based on the results of the matching process in step S230, whether the iris data D23 to be matched corresponds to the same iris as the reference iris data D13.

[0061] Step S234: If it is determined in step S232 that the iris data D23 to be matched corresponds to the same iris as the reference iris data D13, the user interface control unit 156 unlocks the authentication device 100. When unlocking, the user interface control unit 156 may display a message screen on the display unit 103 informing the user that authentication has been successful, for example as shown in Figure 5(D). Alternatively, the user interface control unit 156 may also notify the user that authentication has been successful by outputting sound from the sound output unit 103A. The user interface control unit 156 may, for example, display the screen shown in Figure 3(C) for a predetermined time, and then display, for example, the home screen or an application screen.

[0062] Step S236: If it is determined in step S232 that the iris data D23 to be matched does not correspond to the same iris as the reference iris data D13, the user interface control unit 156 controls the authentication device 100 to notify the user of the authentication error by display or sound output.

[0063] According to the above configuration, in this embodiment, at the stage of the iris portion data, which is the format of the captured image data, the processing in steps S218 and S220 determines whether or not the iris in the captured image data obtained this time can be used for authentication processing. As a result, if it is determined that the iris in the captured image data cannot be used for authentication processing, the time required for the subsequent normalization and feature extraction process to generate the matching target iris data can be omitted, and the captured image data can be acquired again. This reduces the time required for iris authentication.

[0064] Furthermore, in this embodiment, during iris authentication, the captured image data obtained over a certain period of time is used in steps S208 and S210 to determine whether or not the captured eye is performing eye movements. If it is determined that the captured eye is not performing eye movements, the system does not proceed to the subsequent iris authentication process. With this configuration, this embodiment can effectively prevent fraudulent practices such as performing iris authentication by capturing images of a person's eyes, including photographs or drawings. As a result, the security of iris authentication is improved.

[0065] Furthermore, in this embodiment, if an error occurs, such as when eye movement is not detected, or when the iris portion data extracted from the captured image data is determined to be unusable as reference iris data or matching iris data, the system provides notification via display or sound. This allows the user to accurately understand what kind of error has occurred and take appropriate action, such as re-imaging the eye. In addition, such notification enables the provision of iris authentication services appropriately to people with visual impairments and hearing impairments.

[0066] Note that the eye movement detection process in step S210 may be omitted. In this case, in step S208, instead of obtaining multiple image data corresponding to a certain period, image data may be obtained as, for example, a single still image, and the iris portion data may be extracted in step S216.

[0067] Furthermore, when registering the reference iris data as shown in the flowchart of Figure 2, detection of whether or not eye movement is occurring (steps S208, S210) and notification according to the detection result (steps S212, S214) may also be performed.

[0068] Furthermore, at least some of the functional units in the control unit 105 of the authentication device 100 in this embodiment may be provided in, for example, other devices or external devices such as servers that are communicatively connected to the authentication device 100. Similarly, the storage unit 106 may also be provided in other devices or external devices such as servers that are communicatively connected to the authentication device 100. In this case, for example, the authentication device 100 of this embodiment may function as a thin client terminal and transmit captured image data to the server. In this case, the server may perform eye movement determination, extraction of iris data, usability determination, generation of iris data to be matched, generation and registration of reference iris data, authentication processing, transmission of display data for notification and sound output data to the authentication device 100, etc.

[0069] Alternatively, the processing of the authentication device 100 may be performed by recording a program for realizing the functions of the authentication device 100, etc., on a computer-readable recording medium, loading the program recorded on this recording medium into a computer system, and executing it. Here, "loading the program recorded on the recording medium into a computer system and executing it" includes installing the program into the computer system. Here, "computer system" includes hardware such as the OS and peripheral devices. Furthermore, "computer system" may include multiple computer devices connected via a network including communication lines such as the Internet, WAN, LAN, and dedicated lines. Furthermore, "computer-readable recording medium" refers to portable media such as flexible disks, magneto-optical disks, ROMs, CD-ROMs, and storage devices such as hard disks built into the computer system. Thus, the recording medium storing the program may also be a non-transient recording medium such as a CD-ROM. Furthermore, the recording medium also includes internal or external recording media that are accessible from the distribution server for distributing the program. The program code stored on the distribution server's recording medium may be different from the program code in a format executable by the terminal device. In other words, the format in which the program is stored on the distribution server is irrelevant, as long as it can be downloaded from the distribution server and installed in an executable format on the terminal device. Furthermore, the program may be divided into multiple parts, each downloaded at a different time and then combined on the terminal device, and different distribution servers may distribute each of the divided programs. In addition, "computer-readable recording medium" includes volatile memory (RAM) within computer systems that act as servers or clients when a program is transmitted over a network, which retains the program for a certain period of time. Moreover, the program may only be used to implement some of the functions described above. Furthermore, the program may be a so-called differential file (differential program) that can implement the functions described above in combination with a program already recorded in the computer system. [Explanation of symbols]

[0070] 100 Authentication device, 101 Communication unit, 102 Imaging unit, 103 Display unit, 103A Sound output unit, 104 Operation unit, 105 Control unit, 106 Storage unit, 151 Eye movement determination unit, 152 Iris corresponding area extraction unit, 153 Availability determination unit, 154 Iris data generation unit, 155 Authentication processing unit, 156 User interface control unit, 161 Reference iris data storage unit

Claims

1. An iris-corresponding portion extraction unit extracts iris-corresponding portion data from image data obtained through imaging, A usability determination unit determines whether the iris data can be used for iris authentication based on the ratio of the area of ​​the iris corresponding portion corresponding to the iris data extracted by the iris corresponding portion extraction unit to the area of ​​the iris corresponding portion corresponding to the reference iris data, After the usability determination unit determines that the iris portion data is usable for iris authentication, the iris data generation unit generates authentication target iris data in a predetermined format using the iris portion data, The system includes an authentication processing unit that performs an authentication process by comparing the iris data to be authenticated with reference iris data that is stored in advance as reference iris data for the authentication process. In response to the registration of the aforementioned reference iris data, The iris portion extraction unit extracts iris portion data from the captured image data, The usability determination unit determines whether the extracted iris portion data can be used as reference iris data based on the ratio of the area of ​​the iris portion corresponding to the extracted iris portion data to the total area of ​​the iris calculated based on the captured image data, The iris data generation unit generates reference iris data, which is iris data that shows feature quantities, using the iris portion data that the usability determination unit has determined to be usable. Authentication system.

2. The aforementioned reference iris data is the same as the aforementioned reference iris data. The authentication system according to claim 1.

3. The system further includes a user interface control unit that outputs a notification reflecting the determination result from the aforementioned availability determination unit, either through display or sound. The authentication system according to claim 1 or 2.

4. The authentication processing unit uses a trained model constructed by learning the results of matching the iris data to be authenticated with the reference iris data. The authentication system according to any one of claims 1 to 3.

5. An iris-corresponding portion extraction unit extracts iris-corresponding portion data from image data obtained through imaging, A usability determination unit determines whether the iris data can be used for iris authentication based on the ratio of the area of ​​the iris corresponding portion corresponding to the iris data extracted by the iris corresponding portion extraction unit to the area of ​​the iris corresponding portion corresponding to the reference iris data, After the usability determination unit determines that the iris portion data is usable for iris authentication, the iris data generation unit generates authentication target iris data in a predetermined format using the iris portion data, The system includes an authentication processing unit that performs an authentication process by comparing the iris data to be authenticated with reference iris data that is stored in advance as reference iris data for the authentication process. In response to the registration of the aforementioned reference iris data, The iris portion extraction unit extracts iris portion data from the captured image data, The usability determination unit determines whether the extracted iris portion data can be used as reference iris data based on the ratio of the area of ​​the iris portion corresponding to the extracted iris portion data to the total area of ​​the iris calculated based on the captured image data, The iris data generation unit generates reference iris data, which is iris data that shows feature quantities, using the iris portion data that the usability determination unit has determined to be usable. Authentication device.

6. An iris-corresponding portion extraction step is performed to extract iris-corresponding portion data from the image data obtained by imaging, A usability determination step that determines whether the iris data can be used for iris authentication based on the ratio of the area of ​​the iris corresponding portion corresponding to the iris data extracted in the iris corresponding portion extraction step to the area of ​​the iris corresponding portion corresponding to the reference iris data, After the usability determination step determines that the iris portion data is usable for iris authentication, the iris data generation step generates authentication target iris data in a predetermined format using the iris portion data; The authentication process includes a step of performing an authentication process by comparing the iris data to be authenticated with reference iris data that has been stored in advance as reference iris data for the authentication process. In response to the registration of the aforementioned reference iris data, In the iris portion extraction step, iris portion data is extracted from the captured image data. In the usability determination step, it is determined whether the extracted iris portion data can be used as reference iris data based on the ratio of the area of ​​the iris portion corresponding to the extracted iris portion data to the total area of ​​the iris calculated based on the captured image data, In the iris data generation step, reference iris data, which is iris data showing feature quantities, is generated using the iris portion data that has been determined to be usable in the usability determination step. Authentication method.

7. A computer as an authentication device, An iris-corresponding portion extraction unit extracts iris-corresponding portion data from image data obtained through imaging. A usability determination unit determines whether the iris data can be used for iris authentication based on the ratio of the area of ​​the iris corresponding portion corresponding to the iris data extracted by the iris corresponding portion extraction unit to the area of ​​the iris corresponding portion corresponding to the reference iris data. After the availability determination unit determines that the iris portion data is usable for iris authentication, an iris data generation unit generates authentication target iris data in a predetermined format using the iris portion data. The authentication processing unit performs the authentication process by comparing the iris data to be authenticated with reference iris data that has been stored in advance as reference iris data for the authentication process. It is a program designed to function as such. In response to the registration of the aforementioned reference iris data, The iris portion extraction unit extracts iris portion data from the captured image data, The usability determination unit determines whether the extracted iris portion data can be used as reference iris data based on the ratio of the area of ​​the iris portion corresponding to the extracted iris portion data to the total area of ​​the iris calculated based on the captured image data, The iris data generation unit generates reference iris data, which is iris data that shows feature quantities, using the iris portion data that the usability determination unit has determined to be usable. program.

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