Study Of Image Inpainting Method Based On Partial Differential Equations (PDEs)

Image inpainting technique is the process of filling in the missing or degraded information of the inpainting domain using the known information of the image so as to gain the whole image. Image inpainting as well as image denoising belongs to the image restoration category. Nowadays, image inpainting technique has been a new and active research way of the image engineering field.Image inpainting has very wide applications in the fields such as image process, vision analysis, film industry etc including the restoration of old paintings which have collection value, restoring old photos and films which have scratchs, the removal of superimposed texts from the image, the removal of undesired objects, image zooming and image compress coding.Image inpainting includes the non-texture inpainting and texture inpainting.The new methods of the non-texture inpainting are the method based on partial differential equations.This paper mostly deals with the local and non-texture image inpainting based on partial differential equations.Firstly, the paper studys the classic image inpainting models based on the partial differential equations or variational method, namely Harmonic model, TV model and CDD model. In fact, Harmonic model is an isotropic diffusion equation (heat equation). This equation is isotropic during inpainting.TV inpainting model is the extention of the classic TV (Total Variation) denoising model proposed by Rudin, Osher and Fatemi.CDD model overcomes the disadvantage of the TV model not meeting the consistent principle. Then, inspired by TV inpainting model, the paper proposed some improved image inpainting models, namely Perona-Malik diffusion model, selective smoothing model, degenerate diffusion model and selective degenerate diffusion model and put these denoising models into inpainting field. Among these models, degenerate diffusion model and selective degenerate diffusion model can keep the image edges very well during inpainting. The inpainting effect of these two models is far better than that of TV model.Lastly, the paper studys two classic models that simultaneously inpaint and denoise, including TV inpainting and denoising model, CDD inpainting and denoising model, and propose three improved models.That include ALM-TV inpainting and denoising model, ALM-MCF inpainting and denoising model and MCF-ALM inpainting and denoising model. Experiment results show that the models proposed by this paper have better restoration effect and faster speed than classic models...