Lots of pools have such systems, e.g. https://en.m.wikipedia.org/wiki/Poseidon_drowning_detection_system https://en.m.wikipedia.org/wiki/Poseidon_drowning_detec

Lots of pools have such systems, e.g. https://en.m.wikipedia.org/wiki/Poseidon_drowning_detection_system https://en.m.wikipedia.org/wiki/Poseidon_drowning_detection_... It's a straightforward but very meaningful application of computer vision.