Re(4): Awe....some! Posted on November 10, 2017 at 04:51:35 PM by Craig G
My suggestion is completely non-invasive.
We don't need no steenkin' matrix, either.
Since the lines do not vary from day to day we can superimpose our reference background stuff in our video processing. Measure painted lines once, apply findings often.
All we need is a person with an adequate camera that provides video of the throwing player with the ref lines in the same frame. As you know, the geometry from off-center camera angles can be handled thru calculations.
We could have roll-your-own pelota speeds forever.