July 15, 2013 -
Irises do not deteriorate enough to affect biometric identification — this according to a fresh NIST IREX VI study.
According to NIST, work was conducted to determine whether iris recognition accuracy decreases with time lapsed between enrollment and later recognition. The study looked to draw conclusions for a healthy population, arguing that “medical conditions and injuries can rapidly and severely affect recognition, so these are out of scope.”
“Using two large operation datasets, we find no evidence of a widespread iris ageing affect,” the report notes. “Specifically, the population statistics (mean and variance) are constant over periods of up to nine years. “
A widely-publicized report from 2012 from the University of Notre Dame which found that iris recognition was susceptible to aging affecting the recognition process, gets particular mention in the report, as NIST’s findings challenge the University’s report.
“We show that template ageing reported in the Notre Dame studies is largely due to systematic dilation change over the collection period. Pupil dilation varies under environmental and several biological influences, with variations occurring on timescales ranging from below one second up to several decades. Our data suggests that the natural construction of pupil size over decades does not necessitate re-enrollment of a well enrolled iris.”
The NIST study looked at 7876 records from a registered traveler deployment system, with use of the system on forty or more occasions over a period 4-9 years.
IREX, which stands for the Iris Exchange Program, was established by NIST in 2008 and has been conducting studies and measuring the efficacy of algorithms for iris recognition systems ever since.
The new report, available on the NIST website, also includes technical considerations for organizations interested in ageing studies and includes a recommendation that ageing studies should adopt the tight image acquisition controls used in many opthalmalogical studies.
NIST has had a strong focus on iris as of late. Reported previously, last week NIST delivered a new publication for Personal Identity Verification cards, which now adds iris images and on-card fingerprint comparison as options for compliant cards.