This is a cool concept, though it appears to only care about the total number of people being below a set threshold regardless how people interact (i.e. maintain social distancing)

Shameless plug: two friends and I put together a small app that uses security cameras feed to calculate real-time density + estimate "safe" space capacity:

Demo video: https://www.youtube.com/watch?v=RTgxhptePxM Demo site: https://flou.fyi/ (takes a bit to load)