Improved Iris Location Algorithm
Iris location is a crucial step in iris recognition.Taking into consideration the fact that in the inner of pupil,there would have some light spots because of reflection,this paper improved the commonly used coarse location method.It utilized the gray histogram of iris graphics,firstly according to the nature of gray level distribution of pupil to compute the binarization threshold,adopting the method of average of the center of chords to coarsely estimate the center and radius of pupil,so as to decrease the searching range and computation time in fine location.After that,the inner boundary(pupil) was fine located using the algorithm of circular detection in the binary graphic.Compared to the previous algorithms,this method could reduce the error of locating within the pupil.Experiments have shown the applicability and effectivity of this algorithm.