To improve the speed of localization

a fast iris localization algorithm combined a coarse localization and a fine localization.Firstly

pupil area is segmented from eye image by threshold

removing eyelash noise etc from binary pupil area by morphological operation.Then extracting pupil boundary point by line scanning to the pupil area

and using the least-square fitting to determine the inner boundary.Finally

using the circle gradients operator to localize the inner and outer iris boundary.Average localization time cost by the proposed algorithm on more than 100 iris images from CASIA (Version 1.0) is 1.38s

circle gradient operator cost 9.8s

Hough transform method cost 14.3 s.Experiment results showed that the proposed algorithm has a high performance on speed and precision

also has strong robustness for different quality iris image.