I’m sure it can be done with a normal camera and enough light, especially with the advancement of AI technologies in recent years. I haven’t had time to experiment, but if you have an iPhone, you can try this app [1] I installed yesterday to study its feasibility.

On the homepage, there is a video [2] explaining more as well, and their paper [3].

1. https://www.rouast.com/vitallens/

2. https://www.youtube.com/watch?v=_0HHjovI8hc

3. https://arxiv.org/pdf/2312.06892

Intel Meteor Lake+ platforms can use NPU for WiFi 7 Sensing.

Presence (commercial): https://community.intel.com/t5/Blogs/Tech-Innovation/Client/...

Breathing (research): https://www.intel.com/content/www/us/en/research/respiration...

For older Intel wifi radios, there is custom firmware and many research papers: https://dhalperi.github.io/linux-80211n-csitool/