Southampton: New method to identify people by their ears

Research lead | Development opportunity

Scientists at Southampton University have found a way to identify ears with a success rate of almost 100 per cent, using a technique called image ray transform.

The research, carried out by Mark Nixon, John Carter and Alastair Cummings shows how the transform is capable of highlighting tubular structures such as the helix of the ear and spectacle frames, by exploiting the elliptical shape of the helix.

This could be used as the basis of an ear biometric. Nixon first proved that ears were a viable biometric back in 1999. At that point he claimed ears have certain advantages over the more established biometrics, as they have a rich and stable structure that is preserved from birth to old age, and instead of ageing they just get bigger.

The ear also does not change with changes in facial expression. In addition, it is firmly fixed in the middle of the side of the head, against a predictable background. In contrast, face recognition requires the face to be captured against a controlled background.

However, the fact that ears can be concealed by hair led Nixon and his team to come up with new algorithms to make it possible to identify and isolate the ear from the head.

The technique devised by the scientists achieves 99.6% success at enrollment across 252 images, with little confusion with hair and spectacles. These results show great potential for enhancing the detection of structural features.

“Feature recognition is one of the biggest challenges of computer vision,” said Cummings. “The ray transform technique may also be appropriate for use in gait biometrics, as legs act as tubular features that the transform is adept at extracting.”

“The transform could also be extended to work upon 3D images, both spatial and spatio-temporal, for 3D biometrics, or object tracking.  It is a general pre-processing technique for feature extraction in computer images, a technology which is now pervading manufacturing, surveillance and medical applications.”