IRIS RECOGNITION SYSTEM AND METHOD
BACKGROUND
[0001] Identification of humans is a goal as ancient as humanity itself. As technology and services have developed in the modern world, human activities and transactions have proliferated in which rapid and reliable personal identification is required. Examples include passport control, computer login control, bank automatic teller machines and other transactions authorization, premises access control, and security systems generally. As always, identification that is speedy, reliable, and automated is desired over slower, less reliable and manual identification procedures.
[0002] The use of biometric indicia for identification purposes requires that a particular biometric factor be unique for each individual, that it be readily measured, and that it be invariant over time. Although many indicia have been proposed over the years, fingerprints are perhaps the most familiar example of a successful biometric identification scheme. As is well known, no two fingerprints are the same, and they do not change except through injury or surgery. It is equally clear, however, that identification through fingerprints suffers from the significant drawback of requiring physical contact with the person. No method exists for obtaining a fingerprint from a distance, nor does any such method appear likely.
[0003] More recently, the iris of the human eye has been used as a biometric indicator for identification. The pattern of an iris is complex and can contain many distinctive features such as arching ligaments, furrows, ridges, crypts, rings, corona, freckles, a zigzag collaret, and other distinctive features. The iris of every human eye has a unique texture of high complexity, which is essentially stable over a person's life. No two irises are identical in texture or detail, even in the same person. As an internal organ of the eye, the iris is well protected from the external environment, yet it is easily visible even from yards away as a colored disk, behind the clear protective window of the eye's cornea, surrounded by the white tissue of the eye. Although the iris stretches and contracts to adjust the size of the pupil in response to light, its detailed texture remains largely unaltered apart from stretching and shrinking. Such distortions in the texture can readily be reversed mathematically in analyzing an iris image, to extract and encode an iris signature that remains the same over a wide range of pupillary dilations. The richness, uniqueness, and immutability of iris texture, as well as its external visibility, make the iris suitable for automated and highly reliable personal identification. The registration and identification of the iris can be performed using a video-camera without any physical contact, automatically and unobtrusively.
BRIEF DESCRIPTION OF THE FIGURES
[0004] Embodiments of the present invention are illustrated by way of example and not limitation in the Figures of the accompanying drawings in which:
[0005] FIG. 1 is a diagram illustrating an overall structure of a iris recognition system, according to an example embodiment.
[0006] FIG. 2 is a flow diagram illustrating a method for iris recognition, according to an example embodiment.
[0007] FIG. 3A is an acquired image for use in an example embodiment of the iris recognition method.
[0008] FIG. 3B is an acquired image for use in another example embodiment of the iris recognition method.
[0009] FIG. 3C is an acquired image for use in an example embodiment of the iris recognition method.
[0010] FIG. 4 is a flow diagram illustrating a method for locating the origin in an acquired image, according to one example embodiment of the iris recognition method.
[0011] FIG. 5 is a flow diagram illustrating a method for determining penalty costs associated with a selected candidate configuration result, according to an example embodiment.
[0012] FIG. 6 is a step function based on contrast changes for detection of the boundary between a pupil and the iris, and the boundary between the iris and the sclera in an image of an eye, according to an example embodiment of the invention.
[0013] FIG. 7 is an image of an eye showing an occlusion due to a portion of the eye, such as an eyelid, according to an example embodiment.
[0014] FIG. 8 illustrates an example computer system used in conjunction with certain example embodiments.
DETAILED DESCRIPTION
[0015] A system and method for selecting configuration results from a plurality of candidate configuration designs are described herein. In the following description, numerous specific details are set forth. The following description and the drawing figures illustrate aspects and embodiments of the invention sufficiently to enable those skilled in the art. Other embodiments may incorporate structural, logical, electrical, process, and other changes; e.g., functions described as software may be performed in hardware and vice versa. Examples merely typify possible variations, and are not limiting. Individual components and functions may be optional, and the sequence of operations may vary or run in parallel. Portions and features of some embodiments may be included in, substituted for, and/or added to those of others. The scope of the embodied subject matter encompasses the full ambit of the claims and substantially all available equivalents.
[0016] This description of the embodiments is divided into several sections. In the first section, an embodiment of a system-level overview is presented. In the second section, methods for using example embodiments and example embodiments are described. In the third section, an embodiment of a hardware and operating environment is described.
System-Level Overview
[0017] This section provides a system level overview of example embodiments of the invention.
[0018] FIG. 1 is a schematic diagram illustrating a personal identification system, such as an iris recognition system 100, according to an embodiment of this invention. The iris recognition system 100 includes a image acquisition module 200 communicatively coupled to a polar coordinate origin locator 300. The iris recognition system 100 also includes a polar segmentation module 400 communicatively
