In this study we used image processing algorithms to determine pendulum ball motion and present an approach for solving the nonlinear differential equation that governs its movement. This formulae show an excellent agreement with the exact period calculated with the use of elliptical integrals, and they are valid for both small and large amplitudes of oscillation.Also, we reveal some interesting aspects of the study simple pendulum or procedures for determining analytical approximations to the periodic solutions of nonlinear differential equations.