In this paper we introduce a novel method to detect and
localize abnormal behaviors in crowd videos using Social
Force model. For this purpose, a grid of particles is placed
over the image and it is advected with the space-time average
of optical flow. By treating the moving particles as
individuals, their interaction forces are estimated using social
force model. The interaction force is then mapped into
the image plane to obtain Force Flow for every pixel in every
frame. Randomly selected spatio-temporal volumes of
Force Flow are used to model the normal behavior of the
crowd. We classify frames as normal and abnormal by using
a bag of words approach. The regions of anomalies in the
abnormal frames are localized using interaction forces. The
experiments are conducted on a publicly available dataset
from University of Minnesota for escape panic scenarios
and a challenging dataset of crowd videos taken from the
web. The experiments show that the proposed method captures...