Beam hardening correction using polynomial fitting based on reprojection

In X-ray industrial computed tomography (ICT), beam hardening caused reconstruction image artifact and distortion. To overcome this affect, a beam hardening correction method using polynomial fitting based on reprojection was presented. The method segmented the original CT image into different sections and set pixel value of the object ones to 1 to yield a binary image, then reprojected the binary image to obtain the thickness set of X-ray penetrating specimen, fitted the relationship between the thickness and the polychromatic projections by polynomial to establish the beam hardening correction model to calibrate the projections. Compared with conventional polynomial fitting correction technique, the proposed method doesn't need wedge-shaped phantom that is used to acquire the attenuation values at different thickness to establish the correction model. Research shows this method can eliminate beam hardening affect effectively.