Pitching speed determined from video?

If you video tape a pitcher using a 60 frame per second camera, can you relatively determine the speed of a pitch if at release the ball is in hand and the next frame it is gone and not seen on the video in the following frame. My son was last clocked with a gun 11 months ago at 55mph.
I know from the pain in my glove hand he is throwing harder and his ball is moving. just wanted to know if this could equal 60 mph or greater if you can’t see the ball in flight in the next frame of video. are there any calculations I can use to extrapolate the speed.

Jim

I remember Hoseman had a great website but I’m not sure how often he monitors the forums.

You could always do it the old fashion way.

Make a backdrop thats about 2-3 feet. Mark out measurements for feet inches. Then try to get a camera to a position where you see the the first and last measurements of the backdrop at the ends of both sides. Have him pitch and try to get it right along the backdrop. See how long it takes in seconds for the ball to move the 2 or 3 feet. Then convert the feet to cm. Then convert the cm per second to miles per hour.

Thats what I did about 4 months ago lol. Its hard to set up but it works.