Incomplete Cholesky Decomposition Conjugate Gradient Model

Super-resolution image reconstruction is a technique to estimate a high-resolution (HR) image from several low-resolution (LR) images,providing that the LR images are sub-sampled and displaced by different amounts of sub-pixel shifts.The maximum a posteriori (MAP) formulation has become one of the most popular approaches.However,the model-solved methods such as steepest decent (SD) and conjugate gradient (CG) have slowed convergent speed;much process time is still in need.To solve this problem,a preconditioned conjugate gradient method is given in this paper.This method uses incomplete Cholesky decomposition to get the preconditioner and to lower the condition number of the coefficient matrix.The proposed method is tested on aerial images and fruit images.The results indicate that it has quick convergent speed and process speed than SD method and CG method does.