System and method for iris data acquisition for biometric identification

• US 9,192,297 B2
• Filed: 03/05/2013
• Issued: 11/24/2015
• Est. Priority Date: 09/01/2007
• Status: Expired due to Fees

• Current Assignee: EyeLock LLC (VOXX International Corporation)
• Original Assignee: EyeLock LLC (VOXX International Corporation)
• Inventors: Hanna, Keith J.
• Primary Examiner(s): Park, Edward
• Application Number:
  US13/786,093
• Publication Number:
  US 20130182094A1
• Time in Patent Office: 994 Days
• Field of Search: 382/115, 382/124, 382/103
• US Class Current: 1/1
• CPC Class Codes: A61B 3/14 Arrangements specially adapted for eye photography apparatus or arrangements for taking photographs per se G03B
• CPC Class Codes: G06V 10/20 Image preprocessing
• CPC Class Codes: G06V 40/19 Sensors therefor
• CPC Class Codes: G06V 40/193 Preprocessing; Feature extraction

Abstract

A system and related method for acquiring high quality images of the iris of an unconstrained subject comprising a camera; a controllable focusing component; a focus controller component that controls the lens to focus at successively different points within a focus range, such focus control performed without any input from measurement of whether the image is in focus or out of focus, be it based from measurements of the image or other distance metrics to the subject; and a sharpness detection component that rejects the most out-of-focus images based on measurement of focus on the image is disclosed.

Claims

1. A method for dynamic control of biometric image processing in association with an unconstrained subject, the method comprising:

(a) acquiring, by a sensor, a first image of an iris of an unconstrained;

(b) comparing, by a detection component, a quality metric of the first image against that of one or more images of the iris of the unconstrained subject that are stored in memory and acquired prior to the first image, the memory being progressively updated to store a best available set of images of the unconstrained subject for further processing including biometric matching, wherein the quality metric of the first image is determined based on at least one of sharpness, contrast, or area of the exposed iris on the acquired image; and

(c) determining to update the memory by storing the first image in the memory in place of at least one of the one or more stored images responsive to determining that the quality metric of the first image is greater than that of the at least one of the one or more stored images, and to maintain the one or more images stored in the memory by discarding the first image responsive to determining that the quality metric of the first image is equal to or less than that of the at least one of the one or more stored images;

(d) acquiring, by the sensor, a second image of the unconstrained object for determination of whether to update the memory; and

(e) providing, within a predetermined length of time for iris image acquisition and update to the memory, the best available set of stored images of the iris of the unconstrained subject for further processing.

2. The method of claim 1, wherein (a) comprises acquiring the first image without input from measurement of whether the first image to be acquired is in focus.

3. The method of claim 1, wherein (c) comprises determining whether to acquire the second image of the unconstrained subject based on at least one of an availability of the unconstrained subject for acquiring the second image, or a quality metric of at least one image currently stored in the memory relative to a predetermined threshold.

4. The method of claim 1, wherein (d) comprises acquiring the second image after at least one of acquiring the first image or the determination in (c).

5. The method of claim 1, further comprising determining whether to store the second image in the memory.

6. The method of claim 1, further comprising further processing the best available set of images of the unconstrained subject, independent of whether a quality metric of the best available set of images meets a preferred threshold.

7. The method of claim 1, further comprising determining whether to adjust a focus setting of the sensor prior to acquiring the second image.

8. The method of claim 1, wherein the determination to update the memory is independent of whether the quality metric of the first image meets a preferred threshold.

9. A system for dynamic control of biometric image processing in association with an unconstrained subject, the system comprising:

a sensor, configured for acquiring a first image of an iris of an unconstrained subject;

a memory; and

circuitry configured to implement a detection component, the detection component configured for comparing a quality metric of the first image against that of one or more images of the unconstrained subject that are stored in the memory and acquired prior to the first image, the memory being progressively updated to store a best available set of images of the iris of the unconstrained subject for further processing including biometric matching, determining to update the memory by storing the first image in the memory in place of at least one of the one or more stored images responsive to determining that the quality metric of the first image is greater than that of the at least one of the one or more stored images, and to maintain the one or more images stored in the memory by discarding the first image responsive to determining that the quality metric of the first image is equal to or less than that of the at least one of the one or more stored images, wherein the quality metric of the first image is determined based on at least one of sharpness, contrast, or area of the iris exposed on the acquired image,

wherein the sensor is configured to acquire a second image of the unconstrained object for determination of whether to update the memory, and

wherein the memory is configured to provide, within a predetermined length of time for iris image acquisition and update to the memory, the best available set of stored images of the iris of the unconstrained subject for further processing.

10. The system of claim 9, wherein the sensor is configured to acquire the first image without input from measurement of whether the first image to be acquired is in focus.

11. The system of claim 9, wherein detection component is configured to determine whether to acquire the second image of the unconstrained subject based on at least one of an availability of the unconstrained subject for acquiring the second image, or a quality metric of at least one image currently stored in the memory relative to a predetermined threshold.

12. The system of claim 9, wherein the sensor is configured to acquire the second image after at least one of acquiring the first image, or determining by the detection component to update the memory or to maintain the one or more images stored in the memory.

13. The system of claim 9, wherein detection component is configured to determine whether to store the second image in the memory.

14. The system of claim 9, wherein a processor is configured to further process the best available set of images of the unconstrained subject, independent of whether a quality metric of the best available set of images meets a preferred threshold.

15. The system of claim 9, wherein detection component is configured to determine whether to adjust a focus setting of the sensor prior to acquiring the second image.

16. The system of claim 9, wherein the determination to update the memory is independent of whether the quality metric of the first image meets a preferred threshold.