Iris scanner can tell a live iris from a dead one

It's a staple of film when an iris scanner is involved for some high-security needs for the bad guys to simply kill the person with clearance and cut out their eyeball to gain access. As farfetched as that sounds apparently that exact scenario is a viable way to bypass iris scanner security. Researchers want to block that flaw in modern iris scanners.

The scientists have created an iris scanner that can tell a living iris from a dead iris using a machine-vision system. Researcher Mateusz Trokielewicz from Warsaw University of Technology in Poland and colleagues have created a database of iris scans from living people and form dead bodies. They used those scans to train a machine-learning system to spot the differences in living and dead irises.

The scientists claim that the algorithm they developed can tell living and dead irises apart with 99% accuracy. A database called the Warsaw BioBase Post Mortem Iris dataset was used to train this machine-vision system and has 574 near-infrared iris images collected from 17 different people at various times after they died. The scans were taken between five hours and 34 days after death.

Researchers also added 256 images of live irises to the database using the same iris cameras used on the deceased subjects. That was done to prevent the machine-learning algorithm from being fooled based on differences between cameras. An effort was put into checking the dataset for bias in the images including differences in the way operators take photos. They found little to no distinguishing differences in images in that aspect.

The obvious difference between the images taken of dead irises and live ones was that the eyelids of a deceased person where held open using metal retractors. That was easy for the algorithm to spot. The images were cropped to show the iris alone. The algorithm could still tell live and dead irises apart. However, there is a workaround for hackers looking to use the deceased to gain access to something protected with iris scanning tech. An eye cut from a dead body within five hours or less after death has too few changes for the algorithm to tell it is dead.