Abstract:

Combined the improved forward-and-backward (FAB) diffusion and total-variation (TV) diffusion coupled to the parameter constrained shock filters under the projection of the bi-orthogonal filter, a new hybrid diffusion method of image enlargement is proposed. The improved FAB diffusion enhances weak edges, the shock filter constrained by adaptive coefficient enhances the strong edge and TV diffusion based on the level set method smoothingalong the edge diminishes edge jagged effect. The hybrid partial differential equation（PDE） diffusion has the advantage of the three above PDE diffusion. Furthermore, a bi-orthogonal projection is described to perform an interpolation that is reversible, and the interpolated image satisfies the degradation model strictly. The simulation demonstrates the performance of the proposed method is prominent. Compared with other existing PDE based zoom methods, the zoomed image using the proposed method looks more natural and has better visual effect not only on the strong edges but also on weak edges.