It is amazing how much a trained human can tell from just looking at a single frame of a surgical procedure. A well-trained surgical resident can walk into an operating room where a surgery is underway, and can glance up and with one look at the screen know what kind of procedure it is, what step you are at in the procedure — they know what’s going to happen next, and they can tell if it’s going well or not, using clues like if you’ve got a lot of blood in the field, or from looking at the body language of all the people in the operating room. Is the surgeon stressed out? Has the music been turned down? Are people still talking? What are they saying? There’s all kinds of clues.

Medical doctor and engineer Catherine Mohr, in How will technology transform humanity, New York Times, 16 November 2018