2006-9-19 · Activity Recognition and Room-Level Tracking in an Ofce Environment Christian Wojek, Kai Nickel, Rainer Stiefelhagen fcwojek, nickel, stiefel g@ira.uka.de Interactive System Laboratories Universit at Karlsruhe (TH)¨ Germany Abstract We present an approach for multi-person activity recognition in an ofce environment with simultaneous tracking