Improved Non-local Iterative Back-Projection Method for Image Super-Resolution

The non-local iterative back-projection (NLIBP) algorithm for image super-resolution proposed by Dong et al. can generate high-resolution image with sharp edges well preserved. However it may produce some unpleasant artifacts when applied to images with large shading areas, and the pixel-wise non-local post-processing is high complexity. This paper presents an improved NLIBP fast algorithm. First an edge detection is conducted on the initially interpolated image. Then the use of non-local filter in the modifying process for each initially interpolated pixel can be adaptively controlled according to the edges around, which greatly reduces the time consumption. The experimental results show that our improved algorithm reconstructs higher quality images in both the measure of PSNR and the subjective perception with lower complexity.