Speaking of infrared imaging…researchers Georgia Koukiou and Vassilis Anastassopoulos of the University of Patras in Greece recently published (in the International Journal of Electronic Security and Digital Forensics) the results of a study of 20 volunteers to test sobriety (or not) by means of computer algorithms. By doing infrared scans of the volunteers' faces both prior to and after consuming four drinks (quoting from the MIT Technology Reviewcoverage):
They found that the temperature of the nose was a decent indicator of their subject’s level of inebriation. In all cases, the noses of the beer drinkers were hotter than they were pre-beer. And, more usefully, their noses were almost always hotter than their foreheads.
This phenomenon, in which alcohol dilates blood vessels and increases blood flow in the probiscis, is perhaps not surprising given the broken capillary-induced red snouts characteristic of the chronically inebriated. And it's also leveraged by programs such as Cardiio, Azumio, and Vital Signs Camera, which harness blood flow-induced skin color changes to discern a subject's pulse rate.
For more information, see the above-mentioned MIT Technology Review writeup, along with the coverage in Engadget and Wired.
