IRIS RECOGNITION SYSTEM AND METHOD

• US 20110075893A1
• Filed: 09/25/2009
• Published: 03/31/2011
• Est. Priority Date: 09/25/2009
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Connel, Jonathan H. II, Ratha, Nalini K., Gentle, James E.
• Granted Patent: US 8,452,131 B2
• Time in Patent Office: Days
• US Class Current: 382/117
• CPC Class Codes: G06F 18/2113 by ranking or filtering the set of features, e.g. using a measure of variance or of feature cross-correlation
• CPC Class Codes: G06V 10/771 Feature selection, e.g. selecting representative features from a multi-dimensional feature space
• CPC Class Codes: G06V 40/197 Matching; Classification

Abstract

A system and method for performing an identity search in a database of iris images for a probe iris image includes generating a full-length iris code and a compact iris code for iris images in a database, and generating a full-length iris code and a compact iris code for a probe iris image. The compact iris code for the probe image is scored against all compact iris codes in the database. A fraction of the database is retained based on score data. The full length iris code for the probe image is scored against all the full length iris codes in the retained portion of the database.

Claims

1. A method for performing an identity search in a database of iris images for a probe iris image, comprising:

generating a full-length iris code and a compact iris code for iris images in a database;

generating a full-length iris code and a compact iris code for a probe iris image;

scoring the compact iris code for the probe image against all compact iris codes in the database;

retaining a fraction of the database based on score data; and

scoring the full length iris code for the probe image against all the full length iris codes associated with the compact iris codes in the retained portion of the database.

2. The method as recited in claim 1, wherein scoring the compact iris code includes generating an alignment value, where the alignment value is used in the scoring of the full length iris codes in the retained portion of the database.

3. The method as recited in claim 2, wherein the alignment value from the compact iris code is directly used for the full-length iris code.

4. The method as recited in claim 2, wherein the alignment value accounts for eye rotation in an iris scan.

5. The method as recited in claim 2, further comprising constraining a full-length iris code search by using a compact iris code alignment value.

6. The method as recited in claim 1, wherein the compact iris code is generated by transforming the full-length iris code such that a shorter version is provided that retains individuality information.

7. The method as recited in claim 1, wherein scoring the full length iris code includes matching the full length iris probe to the retained portion in a short list instead of an entire gallery set of the full-length iris codes.

8. The method as recited in claim 1, further comprising determining a best match to ascertain an identity associated with the probe image.

9. A computer readable storage medium comprising a computer readable program for performing an identity search in a database of iris images for a probe iris image, wherein the computer readable program when executed on a computer causes the computer to perform the steps of:

generating a full-length iris code and a compact iris code for iris images in a database;

generating a full-length iris code and a compact iris code for a probe iris image;

scoring the compact iris code for the probe image against all compact iris codes in the database;

retaining a fraction of the database based on score data; and

scoring the full length iris code for the probe image against all the full length iris codes in the retained portion of the database.

10. The computer readable storage medium as recited in claim 9, wherein scoring the compact iris code includes generating an alignment value, where the alignment value is used in the scoring of the full length iris codes in the retained portion of the database.

11. The computer readable storage medium as recited in claim 10, wherein the alignment value accounts for eye rotation in an iris scan.

12. The computer readable storage medium as recited in claim 10, wherein the alignment value from the compact iris code is directly used for the full-length iris code.

13. The computer readable storage medium as recited in claim 10, further comprising constraining a full-length iris code search by using a compact iris code alignment value.

14. The computer readable storage medium as recited in claim 9, wherein the compact iris code is generated by transforming the full-length iris code such that a shorter version is provided that retains individuality information.

15. The computer readable storage medium as recited in claim 9, wherein the method reduces a number of basic bit comparisons through database down-sampling and alignment search restriction.

16. The computer readable storage medium as recited in claim 9, further comprising determining a best match to ascertain an identity associated with the probe image.

17. A system for performing an identity search in a database of iris images for a probe iris image, comprising:

a database configured to store a full-length iris code gallery and a compact length iris code gallery;

a scanner configured to obtain a full-length iris code for a probe iris image;

a transform program configured to generate a compact iris code from the probe iris image; and

a processing module configured to score the compact iris code for the probe image against all compact iris codes in the database, retain a fraction of the database based on score data, and score the full length iris code for the probe image against all the full length iris codes in the retained portion of the database to output best matches to determine an identify associated with the probe iris image.

18. The system as recited in claim 17, wherein the processing module includes an aligner for generating an alignment value, where the alignment value is used in the scoring of the full length iris codes in the retained portion of the database.

19. The system as recited in claim 18, wherein the alignment value accounts for eye rotation in an iris scan.

20. The system as recited in claim 17, wherein the compact iris code is generated by transforming the full-length iris code such that a shorter version is provided that retains individuality information.

21. The system as recited in claim 17, wherein the fraction of the database includes a shortlist of candidates from a gallery along with a list of associated rotational alignment values.

22. The system as recited in claim 21, wherein the full length iris probe is matched to the short list instead of an entire gallery set of the full-length iris codes.

23. The system as recited in claim 17, wherein the system is configured to determine a best match to ascertain an identity associated with the probe image.