Red-eye shows why the camera never lies
The 'red-eye' reducing software inside digital cameras could one day be used to verify a person's age, US researchers say.
Andrew Gallagher, a senior research scientist at Eastman Kodak, developed the technique, which has a range of applications.
Among them are face recognition security systems, age-progression software to identify missing children, and devices that determine whether a person is old enough to buy alcohol or cigarettes.
"We found that the features related to the red-eye artefact, the pupil dilation, are very good features to tell us how old someone is," says Gallagher, who recently filed a patent on the technology.
That's because as people age, the muscles in their eyes naturally weaken, making it more difficult for the eyes to dilate effectively in response to changing light conditions.
In fact, the dilation response goes down by a predictable number: about one millimetre for every decade a person is alive.
Eyes close together
But that's not the only predictable change in human eyes over time.
A baby is born with adult-sized eyes. Though eyes don't grow, the distance between them does.
Using this information, Gallagher built software that finds the red-eye artefact in an image and then, based on the distance between the eyes and how much the eye dilates, estimates the age of the subject.
Currently the software can categorise a person into general age groups such as baby, child, teenager and adult.
"It's very innovative; I've not seen it before," says Professor Tsuhan Chen, an expert in digital video and image processing at the Carnegie Mellon University in Pittsburgh.
"By itself, it's one way of recognising the age. Combining it with other techniques would be the final way to approach this."
In fact, Gallagher hopes to combine the red-eye feature with other face recognition techniques - such as determining the amount of hair, hair colour, and number of wrinkles - to better pinpoint age.
"The idea would be to put as many features together as possible, and that would give you the most accurate reading," he says.
Don't worry. No one will be showing up at your next birthday party with a device that calls you a liar. In fact, Kodak has not yet incorporated this technology into a product.
According to Gallagher, it will mostly likely show up first as a way to organise and retrieve digital images.
Imagine calling up all of the images of your first baby, for instance. An internet version of such a system could be supported by links to advertisers selling age-related products, its developers say.