The texture of iris contains complex structure, which is relatively stable in a person's life. It is almost impossible to find two identical irises. Therefore, iris recognition is considered to be a safer way than other biometric authentication such as fingerprint recognition.
However, this high security may also attract attackers to try to cheat the system by forging iris information, such as using high-quality iris images, video playback or iris molds.
The in-vivo detection function aims to effectively deal with these potential cheating behaviors, and its main purposes include:
1. Anti-deception: Ensure that the iris image comes from a real human eye, not a copied iris image or model. Biopsy can identify the natural physiological reactions of the eyes, such as the contraction and expansion of the pupil to light and the tiny movements of the eyeball, which are difficult to simulate by non-biological samples.
2. Enhance security: By adding an additional authentication layer, real-time detection significantly improves the overall security of the system and reduces the risk of identity fraud.
3. Improve the accuracy: avoid false recognition caused by using non-living iris data, and ensure the accuracy and reliability of the iris recognition system.
Methods to realize in vivo detection usually include but are not limited to:
1. Texture analysis: analyze the texture characteristics of iris and check whether there are unnatural patterns or abnormalities.
2. Motion detection: Observe the dynamic changes of iris and pupil under different lighting conditions, such as blinking and eye movements.
3. Infrared light reflection: When the iris is irradiated by infrared light, the living iris will have a specific reflection mode, while the prosthesis may not have or show different reflection characteristics.
4. Blood flow detection: By analyzing the subtle changes of fundus blood vessels, because there is blood circulation behind the living iris, it can be used to distinguish between true and false.
To sum up, living body detection is an indispensable part of the iris recognition system, which ensures the reliability and security of the authentication process and effectively resists all kinds of fraud attempts.