Diffusion and Fractional Diffusion Based Image Processing

Abstract

We consider the background to describing strong scattering in terms of diffusive processes based on the diffusion equation. Intermediate strength scattering is then considered in terms of a fractional diffusion equation which is studied using results from fractional calculus. This approach is justified in terms of the generalization of a random walk model with no statistical bias in the phase to a random walk that has a phase bias and is thus, only ‘partially’ or ‘fractionally’ diffusive. A Green’s function solution to the fractional diffusion equation is studied and a result derived that provides a model for an incoherent image generated by light scattering from a tenuous random medium. Applications include image enhancement of star fields and other cosmological bodies imaged through interstellar dust clouds. An example of this application is given.