Quality Measurements for Iris Images in Biometrics

Abstract

A method for analyzing the quality of iris images is presented in this paper. Iris Biometrics for personal identification is based on capturing an eye photograph and obtaining a feature vector that allows to identify a human being. Sometimes these images are not good enough due to a variety of reasons: e.g. out of focus, iris covered by eyelashes or eyelids, etc. It is very important to know if an image has enough quality before applying the feature extraction algorithms, in order to avoid bad results and/or save processing power. The methods designed by the authors, have been evaluated with the images of the ICE 2005 database.

Iris segmentation using pupil location, linearization, and limbus boundary reconstruction in ambient intelligent environments

“…Using empirical thresholds, each of the above three factors helps to decide if the pupil has been correctly located or not. A similar example (Fernandez-Saavedra et al 2007) decides upon the quality of iris segmentation using a number of tests aiming at evaluating (a) if the iris is completely contained within the image, (b) pupil dilation/contraction, (c) pupil and iris concentricity, (d) pupil and iris overlap, (e) iris and sclera overlap and, (f) possible occlusions. The limit of both approaches is that the returned 0/1 response does not provide any quantitative information about the reliability for the extracted iris.…”

Design of Biometric Authentication System using Three Basic Human Traits

“…In such a system, an individual who is desirable of recognition gives a claim of identity, usually a PIN and a one-to-one comparison is done by the system to determine if claim is true or not [8] (Wayman 2001). In the identification mode, an individual is recognised by questing through the templates (stored in database) of all the users for a good match.…”

“…In the identification mode, an individual is recognised by questing through the templates (stored in database) of all the users for a good match. Therefore, a one-tomany comparison is made by the system to establish the identity of a user (or negative response is given if the subject is not part of the system's database) without a subject having to put the efforts for claiming his/her identity [8](Wayman2001).…”