Challenges, taxonomy and techniques of iris localization: A survey

A categorical study on iris localization, its challenges and techniques is carried out here. This survey comprehends the historical evolution and present state-of-the-art in iris localization. Most research publications include their primary contribution in iris localization based on tools like Hough Transform, Integro-differential Operator, Active Contour and Deep Learning etc. Majority of the techniques discussed in this paper are popular and efficient enough, however some are unique in their ways. Vast and growing horizon of iris biometric research forces this work to be selective. Our work will be of assistance to someone who is new to iris biometrics and wants to acquire a quick knowledge about iris localization, hurdles before it and various methods to achieve this.