Super-resolutions based on shock filter and non local means with BM3D for congruity

In this paper, we propose two kind of image superresolution methods based on the shock filter and non local means(NLM). One is a method using shock filter to enhance the high frequency components. Another is a method using NLM based on self similarity of images. Compared with interpolation, super-resolution should produce high resolution images by correctly generating their missing high frequency components. The shock filter based method only applies the shock filter to the high frequency components of an enlarged image by the linear interpolation method. Since the proposed method effectively enhances the sharpness of edges and avoids the over enhancement of texture and smooth regions, the enlarged image is natural and the computational complexity is very low. The NLM based method achieves a high resolution image by using self similarity. It is possible to reduce computational complexity and get good quality of the image by the similarity between the low and high resolution images. In order to improve the quality further, we utilize BM3D which is used in denoising for the super-resolution based on image congruity. In simulations, the proposed method objectively and perceptually shows better results than the conventional method.