Review on Iris Recognition System for Unconstrained Environment

Iris being the internal part of the eye, its imaging is a challenge. Most of the research carried out in this domain is with the lot of constraints. This makes iris unsuitable for use in person identification, only it can be used for person authentication. In COVID like era, Where contact less measures are being recommended or followed use of NIR based iris recognition is not very useful. Following aspects of iris recognition systems are covered in this paper namely image acquisition, segmentation, normalization, feature extraction and matching techniques. It is found that no specific method is available in literature which can be used for unconstrained environment. However modification in existing methods can be carried out and be used under unconstrained environment. This Paper is an attempt to compile all research works may be useful for unconstrained iris recognition. This paper covers all major methodologies of iris recognition system which can be used for iris recognition system under unconstrained environment. This review can prove to be useful paper for researchers begin their work in this area.