Analysis of the robustness of iterative restoration methods with respect to variations of the point spread function

It is known that digital image restoration is an ill-conditioned problem in the sense that small deviations like noise in the degraded image produce large deviations in the estimation of the original image. On the other hand, perturbations in the point spread function of the system also result in poor quality restorations. Since the knowledge of the point spread function generally is not exact, the robustness of a restoration method with respect to variations of the point spread function is an important feature to take into account. The paper has the goal of analysing this robustness for some iterative restoration methods