Abnormal pixel detection using sum-of-projections symmetry in cone beam computed tomography

A novel abnormal pixels (APs) detection approach is proposed to remove artefacts from reconstructed images in cone beam computed tomography (CBCT). This approach is based on the symmetry detection of sum-of-projections (SOP). Because some factors affect the SOP symmetry, we combine dyadic wavelet transform-based singularity detection to extract the APs. Next, the Laplacian solution (LS) method is employed to restore the APs in each projection image. Experimental results demonstrate the efficiency of our approach for different imaging tasks.