Triggering events based on the presence of people in a room has been the dream of many geeks and DIY automators for a while. Having your house to turn the lights on or off when you enter or exit your living room is an interesting application, for instance.
Most of the solutions out there to solve these kinds of problems, like the Philips Hue sensors, detect motion, not the actual presence of people — which means that the lights will switch off once you lay down on your couch like a sloth. The ability to turn off music and/or the TV when you exit the room and head to your bedroom, without the hassle of switching all the buttons off, is also an interesting corollary. Detecting the presence of people in your room while you’re not at home is another interesting application.
Read Detecting People With a Raspberry Pi, a Thermal Camera and Machine Learning via IoT For All
An interesting link found among my daily reading