Color image restoration by quaternion diffusion based on a discrete version of the topological derivative

A new method for color image denoising is presented. This work considers three color channels as a whole by using quaternion diffusion. We use concept of topological sensitivity analysis. The diffusion coefficients are computed by a proposed cost function of the Topological Derivative. Finally, the effectiveness of this method for color image restoration is verified by several numerical experiments. This method is also suitable for gray image denoising by complex diffusion.