Nah, it's definitely 2B fps, the frames are just 1x1 wide and a lot of the interesting output comes from the careful synchronization, camera pointing, and compositing of nearly a million 1x1 videos of effectively identical events.

And there are 1 million milliseconds every ~15 minutes. It doesn't take that long to capture all the angles you need so long as you have an automated setup for recreating the scene you are videoing.