Streak Artifact Reduction in X-ray CT by Separation of ROI

Most of commercial computed tomography (CT) system employs filtered back projection (FBP) based algorithm to reconstruct tomographic image. Although FBP originated from an analytical solution, it generates streak artifacts during practical implementation due to interpolation between projection lines. The presence of streak artifacts will result in misinterpretation of tomographic features especially for the sample with line features. In this paper a simple method is proposed to reduce these streak artifacts. This method separates region of interest (ROI) into two parts and extract streak artefact information from one ROI to reduce artefact in another ROI. Numerical simulation using modified Shepp-Logan phantom shows significant reduction of streak artefact in tomographic image.