An adaptive image mixed noise removal algorithm based on MMTD

Mixed noise composed by Gaussian noise and Salt-Pepper noise is an ever-present noise model in the image. This paper proposes an adaptive image mixed removal algorithm based on measure of medium truth degree(MMTD). According to the feature and density of noise, it adaptively alters the detection window size. Then it defines the predicates and establishes the relation between gray level and truth interval of predicates. Finally, uses the distance ratio function to measure the similarity degree between the considered pixel and the normal pixel in the detection window and to remove the noise pixel. By sample simulation and classic PSNR evaluation, it shows the adaptive image mixed noise removal algorithm (AdpMMTD) brings about a good performance in removing mixed noise and preserving fine details.