Improved algorithm of iris localization based on Hough transform and mathematical morphology
Liyu Huang · Computer Engineering and Applications Journal · 2012
Iris location,an important preprocessing procedure in iris recognition,is to detect inner and outer boundaries of iris in an iris image.The traditional iris location algorithm is based on simple Hough transform,but this method owns time consuming operation and low location accuracy.According to the grayscale features of eye images,a novel iris location algorithm,which combines mathematical morphology with Hough transform,is presented.The eye image is preprocessed by using morphological filter.The binary image is extracted and processed by morphology for pupil separation.By means of Sobel operator and least square method,the inner-boundary-points of iris are determined and the inner boundary is fitted.The outer boundary is also determined by Hough transform with morphology and the apriori knowledge about iris image.The test results show that the proposed algorithm has better performance in location accuracy and operation speed,and can be suitably used as practical preprocessing algorithm in iris recognition.