Iris Segmentation System Based on Approximate Feature Detection with Subsequent Refinements

A system of methods for iris region location and segmentation in frontal eye images is presented. Input data are images used in modern iris recognition systems, output contains coordinates of inner and outer iris borders and mask of visible iris region or decision that image does not contain iris of acceptable quality. System processing starts with approximate detection of eye center position followed by approximate detection of inner and outer borders of iris region. If one of the borders is not detected, an additional attempt to locate it is performed with the help of alternative methods. Finally precise borders are detected at last steps of processing by specially designed method.