UCF Computer Vision REU 2012 Paul Finkel 6/25/12 Weeks 5 & 6 Presentation UCF Computer Vision REU 2012 Paul Finkel 6/25/12

Correlation Coloring Calculated correlation between rows of videos Sampled matrices Histogram of optical flow (HOF) HOF > sampled matrices Results show: High correlation in highly dense crowds Low density crowds have mixture of high and low correlation “lines” separate oppositely moving groups Where panic happens

Visualizing Density Changes Calculate entering and exiting matrices Observe a specific section (e.g. 10x10) Sum up how many entered Sum up how many exited Density change = # entered - # exited Density change < 0 => density decreased Density change > 0 => density increased

Visualizing Density Changed (cont'd) Smoothed surf plot helps visualize how density changes between frames Dρ/Dt = δρ/δt + ρ.v Δ Lagrangian Eulerian