Biometric identification is a field with a long history, dating back to fingerprints being used as signatures in ancient Babylon in the second millennium BC.
Today, many smartphones include fingerprint scanners and you can also be identified with your palm veins, DNA, face, retina, iris, hand geometry, voice, typing rhythm and even your odour.
But now there's a new entry to that list. Researchers at Hong Kong Baptist University have developed a "lip motion password" which -- you guessed it -- uses the motions of your lips to create a password.
Based on lip shape, texture, movement and sound, their computational model can tell people apart. Cheung Yiu-ming, who led the research, : “The same password spoken by two persons is different and a learning system can distinguish them.”
There are several advantages of a lip password over conventional security, he added. It's resistant to mimicry, based on a combination of motion and content, less susceptible to background noise than voice authentication, can be quickly changed or reset, and has no language barrier.
Potential applications, Cheung believes, include financial transaction authentication on mobile devices, ATM transactions and credit card user passwords. It could be used to strengthen security access systems on private property, especially if combined with other techniques, like face recognition.
The technology was granted a US patent in 2015.