Caption of 

	BatGroup3DTracking-Wu-etal-ICCV2009.wmv

The video shows the views of three cameras, which were placed near a cave 
entrance in the order camera C, B, and A.
For viewing ease, we prepared a video that is a slow-motion version of the 
original data.  Note that bats fly at a speed of ~8 m/s. The 93 frames of 
the video correspond to 0.75 seconds.

The video shows 19 bats, as they were tracked automatically by our system, 
and their reconstructed 3D flight trajectories. 
The camera views and the 3D trajectories are shown synchronized in time. 
We used the same color to represent a specific bat across views and also 
for its 3D trajectory. 

When bats are occluding each other in one camera view, we show this event 
by a green box around the relevant measurements.
All except one occlusion were interpreted correctly by our system due to 
our track-to-track fusion technique. This can be verified by checking the 
color of the segmented bats before and after occlusion.  The one occlusion 
event that our system did not resolve correctly occurred at frame 5065 in 
camera C. The system switched the tracks of the "white" and "pink" bats.  
Note that correct interpretation of this event is difficult because these 
two bats were only visible together in the view of camera C, and the "pink" 
bat did not appear in the view of camera B while the "white" bat did not 
appear in the view of camera A.

Occlusion events happen at:

Camera A: frames 5002-5004
Camera A: frames 5039-5940
Camera A: frames 5049-5962
Camera B: frames 5005-5010
Camera B: frames 5026-5027 
Camera B: frames 5031-5034
Camera B: frame 5037
Camera B: frame 5050
Camera B: frames 5059-5067
Camera B: frames 5070-5078
Camera C: frames 5059-5070