Not to get TOO geeky but the Math has been there waiting for the computers to catch-up. It's been used in wide aperature and conformal mapping for Sonar for about 3 decades. Essentially a series of 4-D (space-movement) time delays that lets the shape of the ship or boat emulate and enlarge the parabolics needed. Sonar being low data rate, it was implementable. I used Cinci GE's Cray XMP (the equivalent computing power of a Nintendo 64 I think, lol) to run the simulations to get it to real-time.
This? Think of face recognition in reverse. Add movement. Add real time but probably at a lot fewer data points. Not sure how many markers they use in lap-top type face recognition compared to the number of drones in the videos. Sometimes, I miss Engineering.