Machine vision out of its depth?

Regulars to these pages know that I like to see machine vision doing good deeds, and here’s a great example of just that.

A company in France has developed a system that monitors swimming pools to detect possible drowning. The system, which goes by the name of Poseidon, uses multiple cameras mounted both above and under the water to keep track of bathers. Proprietary software analyzes the images and sounds an alarm when indications of drowning are detected.

Now I’m not sure what those indications would be, but there are some hints on the website as to the nature of the algorithms used. These imply there’s some motion tracking going on, with deviations from “normal” being flagged as alarms. I would imagine that a body at rest on the bottom for more than a few seconds would trigger such an alarm, as would a swimmer who stops moving forward and begins thrashing about wildly. There’s also a reference to stereo vision, presumably to derive some information about the location of each swimmer.

So far it appears the Poseidon system has only been sold to operators of large public pools – where it has saved many lives – but wouldn’t it be good to see it a standard feature of every backyard swimming pool? Think how many lives could be saved by a low cost drowning detection system. There’s a challenge for all you vision entrepreneurs.