The system Kintense analyses a person's body and figures out where the joints are in order to create a real-time 3D skeleton figure.
An algorithm then recognises movements made by this model that indicate aggressive behaviour, 'New Scientist' reported.
Inspired by Microsoft's gaming sensor Kinect, the system doesn't require people to be facing the camera.
In research trials, certain actions such as kicking were recognised with 90 per cent accuracy, but other movements, like punching and throwing, were trickier to spot.
Kintense, designed by Shahriar Nirjon and colleagues at the University of Virginia, was created to warn medical staff if a patient is acting violently.
However, it can also find application in security cameras, researchers said.
