Ring artifact removal for micro-tomography in synchrotron radiation

Abstract

Ring artifacts are common in tomography reconstructions. These artifacts may arise, in microtomography using synchrotron radiation, from dead pixels in CCD detectors, damaged scintillator screens and instabilities of the synchrotron beam. Ring artifact removal is therefore an important task. We apply an image inpainting algorithm on the sinogram data to reduce ring artifacts in reconstructions. The applied image inpainting algorithm is advantageous in two aspects. First, the proposed method is local, and it affects only the user-specified corrupted region. Second, it utilizes the directional information of level lines, as well as the intensity information, in the sinogram data. Experimental results show that the proposed method is able to compensate both the missing directional information and the distorted intensity information, which reduces ring artifacts in reconstructions. An improvement in reconstruction image qualities is achieved for micro-tomography using the proposed method. A comparison shows that the proposed method may outperform existing methods in terms of reconstruction accuracy.