  A framework is proposed in this paper that is used to segment flow of dense
crowds. The flow field that is generated by the movement in the crowd is
treated just like an aperiodic dynamic system. On this flow field a grid of
particles is put over for particle advection by the use of a numerical
integration scheme. Then flow maps are generated which associates the initial
position of the particles with final position. The gradient of the flow maps
gives the amount of divergence of the neighboring particles. For forward
integration and analysis forward Finite time Lyapunov Exponent is calculated
and backward Finite time Lyapunov Exponent is also calculated it gives the
Lagrangian coherent structures of the flow in crowd. Lagrangian Coherent
Structures basically divides the flow in crowd into regions and these regions
have different dynamics. These regions are then used to get the boundary in the
different flow segments by using water shed algorithm. The experiment is
conducted on the crowd dataset of UCF (University of central Florida).
