, The Register 2004-12-14
"Great Juno comes; I know her by her gait."William Shakespeare, The Tempest
Retinal scans, finger printing or facial recognition get most of the publicity but researchers across the world are quietly labouring away at alternative types of biometrics.
Recognition by the way someone walk (their gait), the shape of their ears, the rhythm they make when they tap and the involuntary response of ears to sounds all have the potential to raise the stock of biometric techniques. According to Professor Mark Nixon, of the Image Speech and Recognition Research Group at the University of Southampton, each has unique advantages which makes them worth exploring.
Recognition by ear has already been used in criminal cases and has the advantage that the ear does not change shape with age. Smiling doesn't confuse ear recognition but hair might. Newer techniques such as the otoaustic effect (the response of the ear to sound) has the advantage that it is non-invasive and yet voluntary. However practical implementation is still some way off.
Recognition by rhythm is so simple it is possible to implement it on smartcards. However results of this so far have been mediocre. Using a piezoelectric sensor built into a smartcard, researchers have so far been unable to reduce the false acceptance of impostors below 15 per cent.
Nixon has conducted extensive research on the use of gait as a biometric. Its advantage is that it is effective at a distance or where only low image resolution footage is available, as with CCTV cameras. Nixon worked with other researchers in the US Defense Advanced Research Projects Agency's HumanID at a Distance project until the scheme was canned "because of US privacy concerns".
The speed at which someone walks or runs has little effect on the biometric, but wearing a trench coat can mask the feet, and using flip-flops can also throw measurements. "Perhaps it's because we in Britain are not used to wearing flip-flops," Nixon commented.
Nixon told El Reg that the techniques researchers in Southampton, MIT and elsewhere have developed investigating the use of gait as a biometric has applications in other fields. Sports analysis, animation in games and early detection of the onset of disease are just some of the potential of the technique.
Nixon was speaking today in London at an Institute of Electrical Engineers' seminar on the Challenge of biometrics. ®