Method and system for generating a key data record

• US 20030156011A1
• Filed: 03/05/2003
• Published: 08/21/2003
• Est. Priority Date: 05/09/2000
• Status: Active Grant

• Current Assignee: Giesecke & Devrient GmbH
• Original Assignee: Giesecke & Devrient GmbH
• Inventors: Muller, Robert, Modl, Albert, Stephan, Elmar
• Granted Patent: US 6,782,120 B2
• Time in Patent Office: Days
• US Class Current: 340/5.82
• CPC Class Codes: G06F 18/00 Pattern recognition
• CPC Class Codes: G06V 40/1347 Preprocessing; Feature extraction

Abstract

It is proposed to combine the advantages of PIN-based protection systems and biometry-based protection systems and avoid the disadvantages of the respective systems by generating the PIN biometrically uniquely. For this purpose it is provided that only characteristic data that are uniquely reproducible are derived from the determined biometric raw data. On the basis of these uniquely reproducible characteristic data a key record is then generated that either constitutes the PIN code or is used to generate the PIN code. The PIN code is thus always reproducible uniquely on the basis of the biometric data. The user need no longer remember the PIN code, and the PIN code cannot be passed on to third parties.

Claims

1. A method for generating a key record for a verification process from a person'"'"'s biometric data, comprising the steps of:

capturing by sensor technology a biometric feature of the person for generating biometric raw data,

deriving characteristic data from the biometric raw data, and

generating a key record in dependence on the mapped characteristic data, always generating the same key record even for differently derived characteristic data when always starting out from the one person'"'"'s same feature for deriving the characteristic data.

2. A method according to claim 1, characterized in that a multidigit PIN code is generated by means of the key record.

3. A method according to claim 1 or 2, characterized in that the biometric feature is a fingerprint.

4. A method according to claim 3, characterized in that the characteristic data are derived by determining a direction vector image (1) of the dermal ridges of the fingerprint by means of the biometric raw data, subdividing the direction vector image (1) into areas (2) of similar total orientation of the papillae, associating with each area (2) a weighted centroid (3) and deriving a graph (4) from the weighted centroids (3) as characteristic data.

5. A method according to claim 4, characterized in that a key record in the form of a multidigit PIN code (7) is generated from the graph (4) by comparing the derived graph (4) with stored graphs (4′

) of different shape for maximum similarity, each stored graph (4′

) having associated therewith a multidigit number that forms the PIN code (7).

6. A method according to claim 3, characterized in that the rough orientation of the dermal ridges is determined as characteristic data, and the determined rough ori- orientation is mapped onto one of several orientation classes by a classification method, each orientation class having its own key record associated therewith.

7. A method according to claim 6, characterized in that the particular key record associated with the orientation classes serves directly as a PIN code.

8. A method according to claim 3, characterized in that the minutiae of the fingerprint are determined as characteristic data.

9. A method according to claim 8, characterized in that the characteristic data of the minutiae are evaluated statistically for generating the key record.

10. A method according to claim 9, characterized in that the average number of minutiae located within predefined concentric circular rings, circular segments or segments of circular rings around the center of the fingerprint are determined in the statistical evaluation.

11. A method according to claim 9, characterized in that the average number of minutiae having a defined orientation is determined in the statistical evaluation of the minutiae.

12. A method according to claim 9, characterized in that the standard deviation of the cumulated, weighted distance of all minutiae from the center of the fingerprint is determined in the statistical evaluation of the minutiae.

13. A method according to claim 3, characterized in that the number of dermal ridges between centers and delta points is taken into account for deriving the characteristic data.

14. A method according to claim 3, characterized in that characteristic data are determined by fractal image compression.

15. A method according to claim 3, characterized in that the average line density of the fingerprint image is determined as characteristic data.

16. A method according to claim 3, characterized in that the local density and/or the average distance of sweat pores on the dermal ridges is determined as characteristic data.

17. A method according to claim 3, characterized in that the presence of intermediate lines between the single dermal ridges is taken into account for deriving the characteristic data.

18. A method according to claim 1 or 2, characterized in that the structure of the iris is used as a biometric feature.

19. A method for authenticating a person on the basis of a biometric feature of the person, comprising the steps of:

generating a verification key record or PIN code according to any of claims 1 to 18,

comparing the verification key record with a reference record likewise generated according to any of claims 1 to 18, and

authenticating the person if the verification key record or PIN code identically matches the reference record.

20. A method according to any of claims 1 to 19, characterized in that the key record or PIN code is stored as a reference record on a data carrier card.

22. A system according to claim 20, characterized by a data carrier, in particular a smart card, on which the key record is stored as a reference record.

21. A system for generating a key record for a verification process from a person'"'"'s biometric data, comprising:

sensors for capturing biometric raw data on the basis of a biometric feature of the person,

a device for deriving characteristic data from the raw data, and

a device for generating a key record on the basis of the characteristic data, the same key record always being generated for differently derived characteristic data when the derived characteristic data always come from the one person'"'"'s same feature.

23. A system according to claim 21 or 22, characterized in that the key record is a multidigit PIN code.

24. A system according to any of claims 21 to 23, characterized in that the biometric data are derived from a fingerprint.

25. A system according to any of claims 21 to 23, characterized in that the biometric data are derived from the structure of an iris.

26. A system for authenticating a person on the basis of biometric data, comprising:

a system according to any of claims 21 to 25,

a comparison device for comparing a key record with a reference record, and

an output device for effecting an authentication of the person if a complete match between key record and reference record is ascertained by the comparison device.