https://github.com/Kevinkeya/BallTrackingPublic/blob/master/tracking-tennis-ball.pdf
Python 3 and OpenCV 3.2 required.
Tennis ball tracking using particle filtering and color mask.
python3 ball_tracking.py -v tennis_aviGH3Ca-7c7IM_04093_04250.avi -u 1.5 -l 1.5 -s 5 -d True
python3 ball_tracking.py -v tennis_avi9WGK1fSdBJs_00112_00250.avi -u 1.5 -l 1.5 -s 5 -d True
In the first window that pops up, pressing n to choose next frame, and pressing r for choosing current frame to label the tennis ball.
In the second window, pressing left button of mouse from top left to bottom right to draw a rectangular for the tennis ball. Make the rectangular as small as possible but do not left out the tennis because the radius and color distribution are both important for the algorithms.
Press c when you are statisfied and r to reset cutting.
Keep pressing r for next frame in the orignal frame. It may be a little slow if the video size is a bit large. There are two other windows showing mask and the likelihood.