Turning a MPG video into a set of coordinates
You can use opencv library with python for image processing.


Use Videocapture object to capture video from video MPG file. 
Do cap.read() to read frame by frame.  
Convert your frame to grayimage by cvtColor().
Use threshold() function with threshold type-4(threshold with invert option) and with max-binary value as 1. Now you got Mat array with 1 for your mouse with zeroes for background.
Now you can search for 1 in the array and get the coordinates.