CHAPTER ONE
INTRODUCTION
1.1       Background of the Study
A biometric system is essentially a pattern recognition system that operates by acquiring biometric data from an individual, extracting a feature vector from the acquired data, comparing this feature vector from the database feature vector. Person authentication has always been an attractive goal in computer vision. Authentication systems based on human characteristics such as face, finger, iris and voice are known Biometrics systems. The basis of every biometric system is to get the input image and generate prominent feature vectors like color, texture, etc.
Today, biometric recognition is a common and reliable way to authenticate the identity of a living person based on physiological or behavioral characteristics. A physiological characteristic is relatively stable physical characteristics, such as fingerprint, iris pattern, facial feature, hand silhouette, etc. This kind of measurement is basically unchanging and unalterable without significant duress. A behavioral characteristic is more a reflection of an individual’s psychological makeup as signature, speech pattern, or how one types at a keyboard.
The degree of intra-personal variation in a physical characteristic is smaller than a behavioral characteristic. For examples, a signature is influenced by both controllable actions and less psychological factors, and speech pattern is influenced by current emotional state, whereas fingerprint template is independent. Nevertheless all physiology-based biometrics don’t offer satisfactory recognition rates (false acceptance and/or false reject rates, respectively referenced as FAR and FRR). The automated personal identity authentication systems based on iris recognition are reputed to be the most reliable we consider that the probability of finding two people with identical iris pattern is almost zero. That’s why iris recognition technology is becoming an important biometric solution for people identification in access control as networked access to computer application. Compared to fingerprint, iris is protected from the external environment behind the cornea and the eyelid. No subject to deleterious effects of aging, the small-scale radial features of the iris remain stable and fixed from about one year of age throughout life.