Iris Outer Boundary Localization Based on Leading Edge Technique

In recent years, the iris biometric occupies a wide interesting when talking about biometric based systems, because it is one of the most accurate biometrics to prove users identities, thus it is providing high security for concerned systems. This research article is showing up an efficient method to detect the outer boundary of the iris, using a new form of leading edge detection technique. This technique is very useful to isolate two regions that have convergent intensity levels in gray scale images, which represents the main issue of iris isolation, because it is difficult to find the border that can separate between the lighter gray background (sclera) and light gray foreground (iris texture). The proposed method tried to find iris radius by seeking in the two iris halves (right and left) circularly, in term of certain angles interval for each half, to avoid the existence of the upper and lower eyelids and eyelashes. After the two radiuses (i.e. for each half) had been determined, the iris final iris radius would be evaluated to the minimum value of them. This method tested on all samples of CASIAv4-Interval dataset, which consist of 2639 samples, captured from 249 individuals, and distributed on 395 classes, the accuracy of the testing was 100% for outer boundary detection.