A registration algorithm for on-line measuring the rotational velocity of a table tennis ball

We propose a registration algorithm for on-line measuring the rotational velocity of a table tennis ball in which the nearest neighbor interpolation method is presented to estimate the intensities of the pixels on the later frame by using the information of the previous frame. The conjugate gradient method is used to seek the optimum of the rotational parameter. Experimental results with both a ball rotated by a rotational machine and a flying ball shot from a catapult machine sufficiently demonstrate the effectiveness of the proposed method.