Nonlinear Digital Hybrid Filter Based on Variational PDE

The drawbacks of the classical variational PDE image restoration models are analyzed from the view of local diffusion in this paper.Then a hybrid image restoration model based on the total variational model and the harmonic model is proposed and its corresponding digital filter is deduced.A hybrid filter is proposed can select coefficients adaptively according to the local gradient of the image.The proposed hybrid filter can not only denoise while preserving edges,but also reduce the staircase effect in smooth regions.Finally,based on the hybrid filter,a generalized algorithm for image denoising,inpainting and zooming is developed.The proposed algorithm has been evaluated qualitatively and quantitatively on several various types of images produced from such as natural and remote sensing.