Level lines continuation based digital inpainting

Inpainting digital models have been since the late 1990s a powerful image reconstruction tool for missing data. After the original work of Bertalmio et al. (2000) several different approaches have been used to tackle the problem. Some are based on partial differential equations to model a transport process and a diffusion process, others are based on the Euler elastica functional. This paper presents a model using the level lines continuation to perform the filling-in of the inpainting domain D. The model is proposed in a way as to satisfy the "connectivity principle". The image u(x,y) is represented by a family of level lines and the missing part of the image is filled-in by the propagation of the available surrounding information, from outside to inside of the inpainting domain D along the level lines of the image. After defining the domain D the restoration process becomes automatic and the final result u(x,y,t_n) is carried out by the evolutionary process starting with the initial degraded image u(x,y,0). Examples on real and textured images show the performance of this proposed model.