Suppose a camera and the need to measure the speed of a ball such as a tennis ball. Usually, the speed of ball is measured with Doppler effect where the pulse difference reveals the speed. Now I want to measure the speed of the ball from the images with Mathematica. You can suppose 1/30 sec shutter speed.
How would you measure the largest speed of the ball in Mathematica?
I. Image Difference method
Shoot two pictures in 1 second interval. From the difference of images, you get the length travelled. By the $\Delta t$ and $\Delta l$ you get the speed over that range. Simply use Mathematica's Image Difference here.
II. Long shutter time method with a glow ball
Like in light-painting, use a fire-ball or glow-ball or light-ball. Now get one photo with long shutter time in a black room with only ball glowing. Measure the length of the glow over certain time. Programmatically, the task is to measure the length of the flight path.
III. Motion blur method
A camera experiences a motion blur with a fast ball. An user suggested a motion-blur method but I could not understand it. Perhaps just sharpen and use the method I above. Two test images are here and here where the ball has travelled about 4 meters in 23 frames.
IV. Some other method to get the speed of ball from images or a video?