Usage
========
Usage:

    ./program_name path/to/images/frame%d.png diameter_of_ball_in_meters

The path to the frames should contain "%d". The program will automatically replace this with the frame number.

Left and right arrow steps one frame back or forth
Up and down arrow steps ten frames back or forth
Mouse click searches for circles in area around click, and if found, sets this circle as the template.
Home key matches all frames against the template.
"P" key prints coordinates and speed to the terminal.