An empirical correction method for beam-hardening artifact in Computerized Tomography (CT) images

A new empirical method has been proposed for the suppression of beam hardening artifacts. It utilizes discrete cosine transform based missing data estimation and an edge-preserving smoothing filter. The method does not need any information about the experiment specification or the X-ray spectrum used and the material being inspected. The corrections are done in the image domain. The proposed method is first tested on three test samples. It is then applied to the cylindrical sample made of Perspex, aluminiumand steel. The results are compared with that of the existing work and the outcome is promising. The horizontal line profile and other parametric comparisons indicate that the proposed method can suppress beam-hardening artifacts significantly. The application of Sobolev space error analysis has also been made to ensure good global reconstruction.