How to recognize a ball in an image and then model it in 3D(HawkEye System)

Question

We are trying to develop HawkEye System used in cricket for our college project. The process used in HawkEye System is as follows:

1. images of the the ba

Answer 1

One camera is enough if you've got the projection/view matrix to get from image space to world space (there are tons of documents out there to do the camera calibration/coordinate transformation). This will get you a vector that points from the camera through the ball. The ball's size can then be used to determine the distance from the camera.

Guess the easiest way to find the ball would be introducing a threshold that "cuts" the ball from the rest of the image. Or use motion detection to extract the ball and/or combine both approaches.