Spatio-Temporal Dynamics

"Spatio-Temporal Dynamics"::-New way to steal passwords
Hackers can speculate PINs by interpreting video of people tapping on their smartphone screens even when the display itself is not visible, according to the presentation shown by the researchers at Syracuse University.
Software used to interpret such video relies on “spatio-temporal dynamics” to measure the distance from the fingers to the phone’s screen, and then guess exact which characters the fingers tap on a keypad.
This research was published by the Association for Computing Machinery last year. The technology is very easy simple for anybody who knows programming, and millions of targets are available due to the flaring use of smartphones.
With a combination of image analysis and motion tracking algorithms, software filled in the gaps, which were remarkably effective at “guessing” the PINs users typed in.
The software figured out the correct password between 40% and 62% of the time on the first guess, which depended on the quality of the video and the zoom ratio. Nearly 82% accuracy was produced after 5 guess that involved using of highest-quality video and 94% accuracy after 10 guesses.