System for iris detection, tracking and recognition at a distance
A stand-off range or at-a-distance iris detection and tracking for iris recognition having a head/face/eye locator, a zoom-in iris capture mechanism and an iris recognition module. The system may obtain iris information of a subject with or without his or her knowledge or cooperation. This information may be sufficient for identification of the subject, verification of identity and/or storage in a database.
1. A method for iris detection at a distance of non-cooperative or cooperative subjects, comprising:
capturing an image of a face of a subject;
processing the image of the face of the subject to identify an eye region that contains at least one eye of the subject;
capturing an image of the identified eye region of the subject using an imaging device;
determining a iris rotational orientation relative to the imaging device of the iris of the at least one eye, including determining whether the iris rotational orientation provides a best iris rotational orientation towards the imaging device, the best iris rotational orientation being determined by algorithms that maximize a function that depends on key features of the iris to provide a point of maximization; and
re-acquiring an image of the eye region if it is determined that the iris rotational orientation does not provide the best iris rotational orientation towards the imaging device.
2. The method of claim 1 , wherein the determining step includes processing the image of the identified eye region to determine if the iris rotational orientation of the subject does not provide the best iris rotational orientation.
3. The method of claim 1 , wherein the determining step includes processing the image of the face of the subject to determine if the face rotational orientation of the subject, and thus the iris rotational orientation, does not provide the best iris rotational orientation.
4. The method of claim 1 , wherein the determining step includes processing the image of the face to determine if the face rotational orientation of the subject does not provide the best iris rotational orientation, and processing the image of the identified eye region to determine if the iris rotational orientation of the subject does not provide the best iris rotational orientation.
5. The method of claim 1 , wherein the image of the face is captured using a multi-band camera.
6. The method of claim 1 , wherein the image of the identified eye region is captured using a zoom camera.
7. The method of claim 1 , further comprising extracting features of an iris of the subject by determining inner and outer borders of the iris in the image of the identified eye region and doing a one dimensional segmentation of the iris in a polar domain.
8. The method of claim 7 , further comprising converting the features of the iris into an iris numeric code.
9. The method of claim 8 , further comprising comparing the iris numeric code with previously generated iris numeric codes for verification and identification of the iris numeric code or for entry of the iris numeric code into a database.