BIOMETRICS AUTHENTICATION METHOD AND CLIENT TERMINAL AND AUTHENTICATION SERVER USED FOR BIOMETRICS AUTHENTICATION

• US 20100315201A1
• Filed: 04/15/2010
• Published: 12/16/2010
• Est. Priority Date: 06/10/2009
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: HIRATA, Shinji, Takahashi, Kenta
• Granted Patent: US 8,320,640 B2
• Time in Patent Office: Days
• US Class Current: 340/5.82
• CPC Class Codes: G06F 21/32 using biometric data, e.g. fingerprints, iris scans or voiceprints
• CPC Class Codes: G06V 10/95 structured as a network, e.g. client-server architectures
• CPC Class Codes: G06V 30/242 Division of the character sequences into groups prior to recognition; Selection of dictionaries
• CPC Class Codes: G06V 40/53 Measures to keep reference information secret, e.g. cancellable biometrics

Abstract

In a biometrics authentication system inputting biometric information and outputting a user ID, speedup of 1:N matching on the side of server achieved when cancelable biometrics authentication is realized in which matching is carried out. During registration, similarity of a feature to a dummy feature is searched and the feature is transformed by using a transform parameter corresponding to a nearest neighboring dummy feature. The transformed feature and a group ID are transmitted to the server and the server registers the transformed feature at the group in a DB. During authentication, like the registration process, similarity search of a feature is carried out and the feature is transformed by using transform parameter corresponding to a nearest neighboring dummy feature. The transformed feature and group ID are transmitted to the server. The server executes 1:1 matching between a template a the group in the DB and the transformed feature.

Claims

1. A biometrics authentication method in which a client terminal transforms a feature for authentication extracted from biometric information of an individual with the help of a transform parameter to obtain a transformed feature for authentication and transmits it to an authentication server,

the authentication server includes a database adapted to store a plurality of transformed features for registration and information specifying the individual by making the correspondence between them and searches said database to specify an individual corresponding to a transformed feature for registration which is the most similar to the transformed feature for authentication,

said client terminal stores in a database on the client side in advance dummy features on the basis in which the feature for registration and the feature for authentication of the biometric information are classified into any of a plurality of groups, an index for identifying the group and transform parameters corresponding to the respective dummy features;

and

said authentication server includes a database for transformed features for registration adapted to store the transformed feature registration transformed from the feature for registration with the help of the transform parameter and information for identifying the individual from which extraction of the feature for registration originates while classifying them into any of said plural groups on the basis of said index,

wherein, during a process for registration of the biometric information, said biometrics authentication method comprises in said client terminal the steps of;

extracting a feature for registration from biometric information acquired from an individual;

searching said database on the client side to specify one dummy feature for registration similar to the feature for registration;

transforming the feature for registration by using a transform parameter corresponding to the specified dummy feature for registration and preparing transformed feature for registration; and

transmitting to said authentication server the transformed feature for registration, an index for registration adapted to specify a group of the specified dummy feature for registration and information for specifying the individual from which extraction of the feature for registration originates,

said biometrics authentication method comprises in said said authentication server the step of;

registering, at a group corresponding to said index for registration in said database for transformed feature for registration, the received transformed feature for registration an information specifying the individual while making the correspondence between them.

2. A biometrics authentication method according to claim 1, wherein said plural features for registration extracted in advance are divided into a plurality of groups pursuant to a predetermined criterion and

a centroid calculated from features for registration contained in one group is set as said dummy feature corresponding said group.

3. A biometrics authentication method based on the biometric information registered in accordance with the method for registration of biometric information as recited in claim 1,

said biometrics authentication method comprising in said client terminal during a process for authentication the steps of:

extracting a feature (y) for authentication from biometric information acquired from an individual;

searching said database on the client side to specify one dummy feature for authentication similar to the feature for authentication; and

transforming the feature for authentication by using a transform parameter corresponding to the specified dummy feature for authentication and preparing a transformed feature for authentication, and

transmitting to said authentication server the transformed feature for authentication and an index for authentication adapted identify a group of specified dummy features for authentication, and

said biometrics authentication method comprising in said authentication server the steps of;

searching a group corresponding to the index (i) for authentication in the database for transformed feature for registration to specify a transformed feature which is the most similar to the transformed feature for authentication;

specifying the individual having the correspondence with the specified transformed feature for registration; and

transmitting to said client terminal the information concerning the specified individual.

4. A biometrics authentication method according to claim 1, wherein in the step of specifying one dummy feature similar to the feature for registration and in the step of specifying one dummy feature for authentication similar to the feature for authentication in said client terminal, Locality-Sensitive Hashing or Approximating and Eliminating Search Algorithm is used.

5. A client terminal used for biometrics authentication in which a transformed feature for registration obtained by transforming a feature for registration extracted from biometric information of an individual with the help of a transform parameter is transmitted to an authentication server and registered therein, wherein

a dummy feature used on which a feature for registration and a feature for authentication of biometric information are classified into any of a plurality of groups, an index for identifying said group, transform parameters corresponding to respective dummy features are memorized in a database on the client side;

the feature for registration is extracted from biometric information acquired from an individual;

said database on the client side is searched to specify one dummy feature for registration similar to the feature for registration;

a transformed feature for registration is prepared by transforming the feature for registration by the use of the transform parameter corresponding to the specified dummy feature for registration; and

the transformed feature for registration, the index for registration adapted to identify a group of the specified dummy feature for registration and information for specifying the individual from which extraction of the feature for registration originates are transmitted to said authentication server.

6. A client terminal used for biometrics authentication according to claim 5,

wherein said plural features for registration extracted in advance are divided into plurality of groups pursuant to a predetermined criterion and

a centroid calculated from feature for registration contained in one group is set as said dummy feature corresponding said group.

7. A client terminal used for biometrics authentication according to claim 5, wherein

a feature for authentication is from biometric information acquired from an individual;

said database on the client side is searched to specify one dummy feature for authentication similar to the feature for authentication;

the specified feature for authentication is transformed by the transform parameter corresponding to the specific dummy feature for authentication to prepare a transformed feature for authentication;

the transformed feature for authentication and an index for authentication adapted to identify the specified group of dummy features for authentication are transmitted to said authentication server; and

information concerning the specified individual is received from said authentication server.

8. A client terminal used for biometrics authentication according to claim 5, wherein in specifying one dummy feature for registration similar to the feature for registration, Locality-Sensitive Hashing or Approximating and Eliminating Search Algorithm is used.

9. An authentication server comprising a database for storing a plurality of transformed features for registration and information specifying an individual by making the correspondence between them and used for a method for biometrics authentication in which said database is searched to specify an individual corresponding to the transformed feature which is the most similar to the feature for authentication, wherein

the transformed features for registration to be stored in said database are divided into a plurality of groups allotted with indexes pursuant to a predetermined criterion;

the transformed features for registration, the index for identifying the group and information for specifying the individual from which extraction of the features for registration originates are received; and

the received feature for registration and the information for specifying the individual are registered at the group corresponding to the index in said database by making the correspondence between them.

10. An authentication server according to claim 9, wherein

the transformed feature for authentication and the index for identifying the group are received;

by searching the group corresponding to the index in said database, the transformed feature for registration which is the most similar to the transformed feature (V) for authentication is specified;

the individual corresponding to the specified transformed feature for authentication is specified; and

information concerning the specified individual is transmitted to the originator of transmission of the transformed feature for authentication.