A real time visual representation of the output from the tracking algorithm. Using the same ROI video from Movie 2 (vial 2, yw females, N=7), per frame each fly is detected, shown by the yellow bounding boxes, and assigned a corresponding number attached by yellow flags. The centers of the bounding boxes in each video frame correspond to the coordinates saved in the algorithms output matrix. The video shows several collisions between flies. Analysis of a larger dataset of 79800 frames (266 flies × 10 seconds × 30 frames s−1) detected 2762 collisions, amounting to ∼3.5% of possible instances. Not every collision leads to switching in identities. As an upper estimate, track label swapping occurs in <2% of the time.