We firstly present a variational approach such that during image restoration, edges detected in the original image are being preserved, and then we compare in a second part, the mathematical foundation of this method with respect to some of the well known methods recently proposed in the literature within the class of PDE based algorithms (anisotropic diffusion, mean curvature motion, min/max flow technique,...). The performance of our approach is carefully examined and compared to the classical methods. Experimental results on synthetic and real images will illustrate the capabilities of all the studied approaches.