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Total variation regularized back‐projection method for spatial resolution enhancement

Iterative back‐projection (IBP) technique is commonly utilized to minimize the error of the super resolution (SR) reconstruction and acquire a high spatial resolution image with appealing visual effect. However, the IBP‐based SR method suffers from the chessboard and ringing effect around edges. In this paper, we employ the total variation as a part of the penalty function to minimize the reconstruction error, which helps to avoid across‐edge smoothing and suppress the above‐mentioned artifacts simultaneously. The experimental results validate that the proposed method leads to significant gain in terms of both the peak signal‐to‐noise ratio and the structural similarity index, and promotes the visual effect of the image considerably. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.