Modified Hough Transforms for Iris Location

Hough transform(HT) is a common algorithm used to detect geometry shape of objects in image processing. Some points satisfied lines, circles and other curves will be detected easily by using HT in image. In iris location system, both the inner boundary and the outer boundary of a typical iris can approximately be taken as circles, so the two circles of iris can be obtained by using HT. In this paper, a modified algorithm for gray image is presented. Experiment results show that the modified algorithm can locate iris accurately.