Comments on “Staircase effect alleviation by coupling gradient fidelity term”

The paper “staircase effect alleviation by coupling gradient fidelity term” (Zhu Lixin and Xia Deshen, 2008 [1]) presented a nonlinear diffusion approach using a coupling gradient fidelity term. Although such approach helps to alleviate the staircase effect to some extent, the model is not sound. Moreover the physical mechanism of this model was explained incorrectly, and there are some theoretical mistakes in their proofs and propositions. We propose a new theoretical analysis of the alleviation staircase effect using a coupling gradient fidelity term.