“…Human motion capture and activity recognition have proved viable in, for example, computer graphics, media production, robotics, and video surveillance applications throughout the years [25,20,1,27,5,26,18,7,8], though it still remains an open and challenging problem. There is however already a body of work interested in the detection and recognition of social interaction between multiple people [11,14], which is particularly difficult since the actions of multiple subjects must be inferred and understood.…”