Detecting deep fakes by detecting heart beats

Deep fakes have so far not learned to simulate heart beats in images, and so they can be detected as fraudulent. But given time they will learn this as well; it’s an arms race.

In other news, heart beats are clearly visible in processed images!

In particular, video of a person’s face contains subtle shifts in color that result from pulses in blood circulation. You might imagine that these changes would be too minute to detect merely from a video, but viewing videos that have been enhanced to exaggerate these color shifts will quickly disabuse you of that notion. This phenomenon forms the basis of a technique called photoplethysmography, or PPG for short, which can be used, for example, to monitor newborns without having to attach anything to a their very sensitive skin.

The Subtle Effects of Blood Circulation Can Be Used to Detect Deep Fakes (via Schneier on Security)

Check out the video at 1:30 and then again at 3:18:

The AI’s are certainly going to know a lot about us.