Iris recognition system and method

• US 7,756,301 B2
• Filed: 01/26/2005
• Issued: 07/13/2010
• Est. Priority Date: 01/26/2005
• Status: Active Grant

• Current Assignee: Gentex Corporation
• Original Assignee: Honeywell International Inc.
• Inventors: Hamza, Rida M.
• Primary Examiner(s): Le, Brian Q
• Application Number:
  US11/043,366
• Publication Number:
  US 20060165266A1
• Time in Patent Office: 1,994 Days
• Field of Search: 382/115, 382/117
• US Class Current: 382/117
• CPC Class Codes: G06V 40/18 Eye characteristics, e.g. of the iris

Abstract

An identification method includes acquiring an image of an eye, approximating the center of the pupil, using the approximated center of the pupil as the origin of a polar coordinate system, segmenting the image of an iris portion of the eye along a radial at an angle, and normalizing a number of data points from the iris portion along the radial at an angle.

Claims

1. A method comprising:

acquiring an image of an eye on a storage device;

approximating the center of the pupil as a function of minimizing differences in a radial distance between the center of the pupil and a boundary of the pupil at a plurality of radial angles using a processor;

using the approximated center of the pupil as the origin of a polar coordinate system;

segmenting the image of an iris portion of the eye along a radial at an angle using a processor; and

normalizing a number of data points from the iris portion along the radial at an angle using a processor.

2. The method of claim 1 further comprising analyzing data points from the iris portion of the radial at an angle to generate an iris signature associated with the data points from the iris portion using a processor.

3. The method of claim 2 further comprising comparing the iris signature to a previously generated reference iris signature using a processor.

4. The method of claim 2 wherein generating an iris signature further comprises encoding the data points from the iris portion.

5. The method of claim 4 further comprising comparing the encoded iris signature to a previously generated and encoded reference iris signature.

6. The method of claim 1 wherein approximating the center of the pupil further comprises:

identifying the pupil of the eye as a blob region; and

finding the center of mass of the blob region using a processor.

8. The method of claim 1 wherein segmenting the image of an iris portion of the eye along a radial at an angle, and normalizing a number of data points from the iris portion along the radial at an angle occur substantially simultaneously.

9. The method of claim 4 wherein encoding the data points from the iris portion includes:

generating a bit-wise template representing image data associated with the iris portion; and

weighting a number of most significant bits associated with the data points from the iris portion.

10. The method of claim 1 wherein acquiring an image of an eye includes acquiring an image where the iris is deformed.

7. A method comprising:

acquiring an image of an eye using a processor;

approximating the center of the pupil using a processor;

identifying the pupil of the eye as a blob region using a processor; and

finding the center of mass of the blob region using a processor;

determining the radial distance between the center of mass of the blob region and a boundary of a pupil at a plurality of angles using a processor;

adjusting from the center of mass to a center of the pupil, wherein the center of the pupil is selected to minimize differences in the radial distance between the center of the pupil and the boundary of the pupil at the plurality of angles using a processor;

using the approximated center of the pupil as the origin of a polar coordinate system;

segmenting the image of an iris portion of the eye along a radial at an angle using a processor; and

normalizing a number of data points from the iris portion along the radial at an angle using a processor.

11. A method comprising:

acquiring an image of an eye that includes an iris and a pupil using a processor;

establishing an origin of a polar coordinate system within the pupil of the image as a function of minimizing differences in a radial distance between a center of the pupil and a boundary of the pupil at a plurality of radial angles using a processor;

segmenting the image of an iris portion of the image along a radial, the radial having an endpoint at the origin using a processor; and

extracting information related to the iris portion of the image using a one dimensional analysis using a processor.

12. The method of claim 11 wherein the iris portion of the image is substantially non circular.

13. The method of claim 11 wherein a substantial portion of the iris portion of the image is occluded.

14. The method of claim 11 further comprising processing information related to the image of the eye that is localized to the portion of the image around the iris and the pupil.

15. The method of claim 11 further comprising processing information related to the iris portion of the image independent of a location of the center of the iris.

16. The method of claim 11 wherein segmenting the image of an iris portion of the image along a radial is done in a polar domain before detecting a border of the iris.

17. The method of claim 11 further comprising analyzing a number of data points from the iris portion of the radial to generate an iris signature associated with the data points from the iris portion using a processor.

18. The method of claim 17 further comprising comparing the iris signature to a previously generated reference iris signature using a processor.

19. The method of claim 17 wherein generating an iris signature further comprises encoding the data points from the iris portion.

20. The method of claim 17 further comprising normalizing a number of data points from the iris portion along the radial at an angle using a processor.

21. A method comprising:

acquiring an image of an eye that includes an iris and a pupil using a processor;

establishing an origin of a polar coordinate system at approximately the center of the pupil of the image using a processor, wherein the approximate center is determined as a function of minimizing differences in a radial distance between a center of the pupil and a boundary of the pupil at a plurality of radial angles; and

radially segmenting the iris portion of the image along a plurality of radials using a processor.

22. The method of claim 21 further comprising normalizing a number of data points from the iris portion along each of the plurality of radials using a processor.

23. The method of claim 22 wherein radially segmenting the iris portion of the image along a radial, and normalizing a number of data points from the iris portion along the radial occurs substantially simultaneously for a particular radial.

24. The method of claim 21 further comprising creating a identifier from a set of data associated with the iris portion of an image from one or more of the plurality of radials using a processor.

25. The method of claim 24 wherein creating an identifier includes generating a bit-wise template representing an image of the iris portion along one or more of the plurality of radials.

26. The method of claim 24 wherein creating an identifier includes weighting selected portions of a set of data associated with the iris portion of an image from one or more of the plurality of radials.

27. The method of claim 21 wherein establishing an origin of a polar coordinate system within the pupil of the image includes substantially centering the origin within the pupil of the image.

28. An apparatus comprising:

an image generator operating on hardware and configured to generate an image of an eye that includes at least a portion of an eye including a portion of a pupil, a portion of an iris and a portion of the sclera;

a polar segmentation module operating on hardware and communicatively coupled to the image generator and configured to receive the generated image produced by the image generator, the polar segmentation module to segment the portion of the iris from the received image wherein a center of the pupil is used as a center for such segmenting and wherein the center is determined as a function of minimizing differences in a radial distance between the center of the pupil and a boundary of the pupil at a plurality of radial angles; and

a data extraction and normalization module operating on hardware and communicatively coupled to the polar segmentation module and configured to receive the generated image from the polar segmentation module, the data extraction and normalization module to determine a portion of at least one radial that is associated with the iris using a one dimensional analysis of the generated image, extracting data from the portion and normalizing the data.

29. The apparatus of claim 28 comprising a polar coordinate origin generator communicatively coupled to the image generator to receive the generated image and to determine an origin for at least one radial used by the polar segmentation module.

30. The apparatus of claim 28, further comprising an encoding module communicatively coupled to the data extraction and normalization module to receive the normalized data and to encode the normalized data.

31. The apparatus of claim 30, further comprising;

a storage device coupled to the encoding module and configured to store previously obtained encoded data; and

a comparator module coupled to the encoding module and to the storage module to receive currently encoded data from the encoding module and the previously obtained encoded data from the storage module and to compare the currently encoded data to the previously obtained encoded data.

32. The apparatus of claim 28, further comprising;

a storage device coupled to the encoding module and configured to store previously obtained data; and

a comparator module coupled to the encoding module and to the storage module to compare currently obtained data from the data extraction and normalization module to the previously obtained data.

33. A computer-readable medium that provides instructions that, when executed by at least one processor of a computer system, cause the computer system to perform operations comprising:

acquiring an image of an eye that includes an iris and a pupil;

establishing an origin of a polar coordinate system within the pupil of the image, wherein the origin corresponds to a center of the pupil determined as a function of minimizing differences in a radial distance between the center of the pupil and a boundary of the pupil at a plurality of radial angles;

segmenting the image of an iris portion of the image along a radial, the radial having an endpoint at the origin; and

extracting information related to the iris portion of the image using a one dimensional analysis.

34. The computer-readable medium of claim 33 wherein acquiring an image of an eye that includes an iris and a pupil includes acquiring an image wherein the iris portion of the image is substantially non circular.

35. The computer-readable medium of claim 33 wherein acquiring an image of an eye that includes an iris and a pupil includes acquiring an image wherein a substantial portion of the iris portion of the image is occluded.

36. The computer-readable medium that provides instructions of claim 33 that, when executed by the at least one processor, further cause the computer system to perform operations comprising:

analyzing a number of data points from the iris portion of the radial; and

generating an iris signature associated with the data points from the iris portion.

37. The computer-readable medium of claim 36 wherein generating an iris signature further comprises encoding the data points from the iris portion.

38. The computer-readable medium that provides instructions of claim 36 that, when executed by the at least one processor, further cause the computer system to perform operations comprising normalizing a number of data points from the iris portion along the radial at an angle.

39. The computer-readable medium that provides instructions of claim 36 that, when executed by the at least one processor, further cause the computer system to perform operations comprising comparing the iris signature to a previously generated reference iris signature.