Capturing and understanding crowd dynamics is an important problem under
diverse perspectives. From sociology to safety management, modeling and pre-
dicting the crowd presence and its dynamics, possibly preventing dangerous
activities, is absolutely crucial. In the literature, crowd has been classied un-
der dierent categories depending on size and focus of attention. This chapter
focuses on spectator crowd, namely that formed by people whose behavior is
constrained by a structured environment, whose focus of attention is mainly
shared, directed to a specic event. We rst propose the backbone of an on-
tology of spectator crowd behavior based on a foundational analysis of both
related literature and S-Hock, a massive annotated video dataset on crowd be-
havior during hockey events. Then, we present a new methodological approach
integrating ontological reasoning, performed with a new description logics based
temporal formalism, with computer vision algorithms, allowing for automatic
recognition of events happening in the playground, based on the behavior of the
crowd in the stands.
