In this paper

the algorithm of global motion estimation is investigated

and a fast global motion estimation algorithm is introduced.The new algorithm is based on nonlinear dense estimation and applies the affine model.In order to reduce the time cost during calculation

three-level pyramid is utilized in the algorithm.It combines outlier detection algorithm based on blocks and feature pixels selection algorithm in the calculation of each pyramid level.The calculation time of global motion estimation is reduced and the accuracy is improved.The experimental results show that the new algorithm is superior to original algorithms in velocity and accuracy.