Biometric security encryption system

• US 6,259,805 B1
• Filed: 03/23/1998
• Issued: 07/10/2001
• Est. Priority Date: 12/04/1996
• Status: Expired due to Term

• Current Assignee: Activcard Ireland, Limited (Assa Abloy AB)
• Original Assignee: DEW Engineering and Development Limited (Trelleborg AB)
• Inventors: Freedman, Gordon S., Hamid, Laurence, Borza, Stephen J.
• Primary Examiner(s): MEHTA, BHAVESH M
• Application Number:
  US09/045,810
• Time in Patent Office: 1,205 Days
• Field of Search: 382/115, 382/116, 382/124, 382/125, 340/825.34
• US Class Current: 382/124
• CPC Class Codes: G06F 18/2415 based on parametric or probabilistic models, e.g. based on likelihood ratio or false acceptance rate versus a false rejection rate
• CPC Class Codes: G06V 40/1365 Matching; Classification
• CPC Class Codes: G07C 9/37 using biometric data, e.g. fingerprints, iris scans or voice recognition

Abstract

A method of registering biometric data is disclosed wherein a number of instances of input biometric data are accepted from a new user during a registration process. Each of these data samples are compared against existing templates to identify those templates posing a significant risk of confusion with a data sample. Those templates are identified and information relating to those templates is stored with the enrolled template of the new user. When a user is identified as the new user, the system automatically verifies that the data sample does not also result in identification as one of the identified templates.

Claims

1. A method of identifying an individual comprising the steps of:

a) receiving a biometric information sample from a biometric information source of the individual;

b) characterising the biometric information sample;

c) comparing the characterised biometric information sample against some of a plurality of stored templates to identify a template that closely matches the characterised biometric information sample, wherein some templates belong to different individuals;

d) based upon data stored associated with the identified template and indicative of further templates relating to different individuals from the plurality of stored templates that are each similar to the identified template and are potentially confusing therewith, determining further templates relating to further individuals different from the individual to which the identified template relates;

e) verifying the identified template by performing the step of comparing the characterised biometric information sample against a template from the further templates to determine a likelihood that the characterised biometric information sample closely matches the template from the further templates; and

f) identifying the individual based on the identified template when a match between the characterised biometric information sample and the template from the further templates has a likelihood outside a first range of likelihoods.

2. A method of identifying an individual as defined in claim 1 wherein the step of comparing the characterised biometric information sample against a template from the further templates to determine a likelihood that the characterised biometric information sample closely matches the template from the further templates is performed for each template from the further templates and wherein the step of identifying the individual is performed when each of the determined likelihoods is outside a first range of likelihoods.

3. A method of identifying an individual presenting a biometric information sample to a system as defined in claim 1 comprising the step of:

prompting the individual to present the biometric information source when the likelihood is within a first range of likelihoods.

4. A method of identifying an individual presenting a biometric information sample to a system as defined in claim 1 comprising the step of:

prompting the individual to present a further different biometric information source when the likelihood is within a first range of likelihoods.

5. A method of identifying an individual presenting a biometric information sample to a system as defined in claim 4 wherein the first biometric information source is a fingertip and the further biometric information source is a fingertip from a different finger of the individual.

6. In a system wherein biometric data are stored in a database, a method of performing one of user authorisation and user identification comprising the steps of:

a) providing a biometric information sample;

b) comparing data based on the biometric information sample and the biometric data to locate data of different individuals within the biometric data that is indicative of a substantial match with the biometric information sample;

c) determining further data from data associated with the located data indicative of a substantial match, the further data indicative of biometric data relating to individuals other than an individual to whom the located data indicative of a substantial match relates that has a known potential for allowing determination of a false acceptance between biometric data and the located data;

d) verifying the identified template by performing the step of comparing the data based on the biometric information sample and the further data from the database to provide comparison results indicating likely data that is a substantial match and likely data that is not a correct substantial match and would result in a false acceptance; and

,

e) when the comparison results are indicative of one substantial match with the biometric information sample, performing at least one of user authorisation and user identification in dependence upon the one substantial match.

7. A method of performing one of user authorisation and user identification as defined in claim 6 comprising the step of:

when the comparison results are indicative of a further substantial match with the biometric information sample, prompting for a further biometric information sample.

8. A method of performing one of user authorisation and user identification as defined in claim 7 wherein the further biometric information sample is a biometric information sample from a different biometric information source.

9. A method of performing one of user authorisation and user identification as defined in claim 6 wherein the step of comparing data based on the biometric information sample and the biometric data is performed only until a first comparison indicative of a substantial match with the biometric information sample results.

10. A method of performing one of user authorisation and user identification as defined in claim 6 wherein the step of performing at least one of user authorisation and user identification comprises performing user identification.

11. In a system wherein biometric data are stored in a database, a method of identifying comparisons indicative of potential false acceptance comprising the steps of:

comparing data based on a biometric information sample associated with first data within the biometric data and the biometric data to locate second data related to another individual within the biometric data that is indicative of a substantial match with the biometric information sample to provide comparison results; and

,

when a comparison result is indicative of a substantial match and the second data is other than the first data, storing information in association with the first data the information indicative of the second data.

12. A method of identifying comparisons indicative of potential false acceptance as defined in claim 11 wherein the step of comparing data is performed until the biometric information sample is compared with the biometric data to identify each possible match.

13. A method of identifying comparisons indicative of potential false acceptance as defined in claim 11 wherein a substantial match is a comparison wherein the likelihood of a match is above a predetermined threshold.

14. A method of identifying comparisons indicative of potential false acceptance as defined in claim 11 wherein the information is indicative of identification.

15. A method of identifying comparisons indicative of potential false acceptance as defined in claim 11 wherein the biometric data comprises templates derived from biometric information, the templates for comparison with captured biometric data.

16. A method of storing data relating to biometric information in a database for use in identifying individuals comprising the steps of:

storing data associated with a first biometric information sample and a corresponding identification of an individual; and

,

storing a list of data associated with other biometric information samples corresponding to identifications of other individuals within the database, some of the biometric data associated with the other biometric information samples having a significant similarity to data associated with the first biometric information sample.

17. A method of storing biometric information in a database for use in identifying individuals as defined in claim 16 wherein the biometric information is fingerprint data.

18. A method of registering biometric information from a source, comprising the steps of:

a) providing an instance of biometric information from the source;

b) storing a template relating to the provided biometric information in a database comprising a plurality of templates;

c) comparing the biometric information against a further template of a different individual to determine a likelihood that the biometric information matches the further template;

d) when the likelihood is within a first range of likelihoods, storing data relating to the further template for use in distinguishing between the stored template and the further template to potentially reduce a number of false acceptances and false rejections in association with the data based on the biometric information.

19. A method of registering biometric information from a source as defined in claim 18 comprising the step of storing the determined likelihood that the biometric information matches the further template in association with the data relating to the further template.

20. A method of storing biometric information in a database for use in identifying individuals as defined in claim 18 wherein the biometric information is fingerprint data.

21. A method of registering biometric information in a database for use in identifying individuals as defined in claim 18 comprising:

providing a plurality of different instances of a same biometric information of an individual from the biometric input device to a processor;

selecting each instance of the plurality of different instances;

for each selected instance comparing that selected instance with other of the different instances of a same biometric information provided by the individual, and determining a registration value corresponding to similarities or differences between each selected instance; and

,

selecting as the biometric template an instance from the plurality of different instances for which the registration value is within predetermined limits.

22. A method of registering biometric information from a source as defined in claim 18 comprising the step of:

when the likelihood is within the first range of likelihoods, storing data relating to a biometric information source selected so as to distinguish between the provider of the previously stored biometric information and the provider of the biometric information from which the further template is determined.

23. A method of registering biometric information from a source, comprising the steps of:

a) providing an instance of biometric information from the source;

b) storing a template relating to the provided biometric information in a database comprising a plurality of templates;

c) comparing previously stored biometric information of different individuals against the stored template to determine a likelihood that the previously stored biometric information related to a different individual matches the stored template; and

,

d) when the likelihood is within a first range of likelihoods, storing data relating to the previously stored biometric information and related to a different individual associated with the data based on the biometric information.

24. A method of registering biometric information from a source as defined in claim 23 comprising the step of storing the determined likelihood that the biometric information matches the further template in association with the data relating to the further template.

25. A method of storing biometric information in a database for use in identifying individuals as defined in claim 23 wherein the biometric information is fingerprint data.

26. A method of registering biometric information from a source as defined in claim 23 comprising the step of:

when the likelihood is within the first range of likelihoods, storing data relating to a biometric information source selected so as to distinguish between the provider of the previously stored biometric information and the provider of the biometric information from which the stored template is determined.