Method of verifying the presence of an eye in a close-up image
First Claim
Patent Images
1. A method for verifying that an eye is present in an image comprised of pixels each having an x, y coordinate location in the image and determining its location comprised of the steps of:
- a. selecting an image which is believed to contain an eye having an iris comprised of a set of pixels and a pupil comprised of a second set of pixels, a radius of the pupil being given as rp and a radius of the iris being given as ri ; and
the eye is believed to be located at a selected location;
b. computing rp /ric. if rp /ri is less than 0.5 then determining a centerpoint xi ;
yi of the iris and a centerpoint xp ;
yp of the pupil and calculating
space="preserve" listing-type="equation">D=((x.sub.i -x.sub.p).sup.2 +(y.sub.i,-y.sub.p).sup.2).sup.1/2d. if D<
0.1 ri reporting an eye image is present at the selected location; and
e. if rp /ri is greater than or equal to 0.5 or D is greater than or equal to 0.1 ri then concluding that an eye is not present at the selected location.
6 Assignments
0 Petitions
Accused Products
Abstract
A method for verifying that an eye is present and accurately located in an image that is used for identifying an individual using iris identification techniques begins with an image in which the eye is believed to be present at a selected location. The image is then subjected to a series of tests to confirm that an eye is present at the selected location.
-
Citations
16 Claims
-
1. A method for verifying that an eye is present in an image comprised of pixels each having an x, y coordinate location in the image and determining its location comprised of the steps of:
-
a. selecting an image which is believed to contain an eye having an iris comprised of a set of pixels and a pupil comprised of a second set of pixels, a radius of the pupil being given as rp and a radius of the iris being given as ri ; and
the eye is believed to be located at a selected location;b. computing rp /ri c. if rp /ri is less than 0.5 then determining a centerpoint xi ;
yi of the iris and a centerpoint xp ;
yp of the pupil and calculating
space="preserve" listing-type="equation">D=((x.sub.i -x.sub.p).sup.2 +(y.sub.i,-y.sub.p).sup.2).sup.1/2d. if D<
0.1 ri reporting an eye image is present at the selected location; ande. if rp /ri is greater than or equal to 0.5 or D is greater than or equal to 0.1 ri then concluding that an eye is not present at the selected location. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A method for verifying that an eye is present in an image comprised of pixels each having an x, y coordinate location in the image and determining its location comprised of the steps of:
-
a. selecting an image which is believed to contain an eye having an iris comprised of a set of pixels and a pupil comprised of a second set of pixels, a radius of the pupil being given as rp and a radius of the iris being given as ri ; and
the eye is believed to be located at a selected location;b. computing rp /ri c. if rp /ri is less than 0.5 then determining a centerpoint xi ;
yi of the iris and a centerpoint xp ;
yp of the pupil and calculating
space="preserve" listing-type="equation">D=((x.sub.i -x.sub.p).sup.2 +(y.sub.i -y.sub.p).sup.2).sup.1/2d. if D<
0.1 ri reporting an eye image is present at the selected location;e. if rp /ri is greater than or equal to 0.5 or D is greater than or equal to 0.1 ri then concluding that an eye is not present at the selected location; f. if rp /ri is less than 0.5 and D is less than 0.1 ri then computing a mean M of values of all pixels in a region corresponding to the pupil in the image; g. if M is not less than 85 then computing a standard deviation S of values of all pixels in a region corresponding to the pupil in the image; h. if M is greater than or equal to 85 or if S is greater than or equal to 0.1M then concluding that an eye is not present at the selected location; i. if M is less than 85 and if S is less than 0.1M selecting each pixel adjacent the pupil pixels and for each selected pixel determining if a value for that pixel V is within the range M-2S<
V<
M+2S;j. growing an expanded pupil to include all pixels adjacent the pupil pixels which have a value V within the range M-2S<
V<
M+2S;k. computing a centroid of the expanded pupil; and l. repeating steps b through k for the expanded pupil. - View Dependent Claims (8, 9, 10)
-
-
11. An improved method for identifying a particular individual of the type in which an image of an eye of a human having a pupil and an iris is acquired, the eye is determined to be present at a selected location in the image, a radius of the pupil being given as rp and a radius of the iris being given as ri ;
- , an iris portion of the eye is isolated, and an iris code is generated and compared to a previously generated iris code wherein the improvement comprises verifying that an eye is present in the image at a selected location prior to generating an iris code in which verifying is comprised of;
b. computing rp /ri c. if rp /ri is less than 0.5 then determining a centerpoint xi ;
yi of the iris and a centerpoint xp ;
yp of the pupil and calculating
space="preserve" listing-type="equation">D=((x.sub.i -x.sub.p).sup.2 +(y.sub.i -y.sub.p).sup.2).sup.1/2d. if D<
0.1 ri reporting an eye image is present at the selected location; ande. if rp /ri is greater than or equal to 0.5 or D is greater than or equal to 0.1 ri then concluding that an eye is not present at the selected location. - View Dependent Claims (12, 13, 14, 15, 16)
- , an iris portion of the eye is isolated, and an iris code is generated and compared to a previously generated iris code wherein the improvement comprises verifying that an eye is present in the image at a selected location prior to generating an iris code in which verifying is comprised of;
Specification