A brief survey on semi-Lagrangian schemes for Image Processing

In this survey we present some semi-Lagrangian schemes for the approximation of weak solutions of first and second order differential problems related to image processing and computer vision. The general framework is given by the theory of viscosity solutions and, in some cases, of calculus of variations. The schemes proposed here have interesting stability properties for evolutive problems since they allow for large time steps, can deal with degenerate problems and are more accurate if compared to standard finite difference/element methods of the same order. Several examples on classical problems will illustrate these properties.