The Optimal And Developed Research On Image Matting Algorithms

Digital image matting is to extract the foreground objects with arbitrary shapes from an image. It is an essential technique to make special effects in film and video production and has enormous potential commercial applications. The existing image matting techniques can't satisfy the increasing needs for speed and effects of matting simultaneously. This paper proposes optimal and developed algorithms for image matting in the efficiency and user interaction.First, based on the Poisson Matting, we present and implement a fast numeric solver called Multigrid Solver for poisson equation on images. Besides, we also set up the strategies on adjusting the input parameters of the multigrid solver in order to obtain optimal results. Through lots of experiments, this method enables the iteration process to converge quickly, and the time cost by the algorithm will be reduced largely compared with other solvers.Second, in the aspect of image matting user interaction, this paper proposes two image matting algorithms with a new user interaction method called scribbling. Compared with the traditional interaction method "Trimap", our method, scribbling, will simplify the interaction between people and computers.Third, in the implementation of the matting algorithms, we have to employ a test called point-in-polygon test to judge whether the point is in the polygon. Our paper proposes two algorithms to respectively solve the point in-out convex polygon problem in O(logn) time complexity and the point in-out polygon problem in O(n). The two new algorithms are easy to be implemented and experimental results show the high robustness and efficiency of the new algorithm.