Improvement of a nonlinear image interpolation method based on heat diffusion equation

Recently many nonlinear interpolation schemes for images have produced images of higher resolution than those produced by linear techniques. But smoothness still exists, especially on edges. The smoothing process can be described as a traditional heat diffusion equation. In this paper, this equation is combined with an improved edge-directed interpolation method to improve visual quality in terms of sharpened edges. Experimental results indicate that the combination of the two methods is capable of achieving images with noticeably sharper edges.