SYSTEM AND METHOD FOR REDUCING OR ELIMINATING STREAK ARTIFACTS AND ILLUMINATION INHOMOGENEITY IN CT IMAGING

摘要

In computed tomography images (102), streak artifacts caused by the presence of metal implants and inhomogeneous estimation of tissue density are reduced or eliminated. The algorithm has two basic steps: 1)illumination correction (104) and 2) adaptive three-Dimensional filtering (106). The algorithm start s by estimating the direction of the streak and the degree of inhomogeneous densities by gray scale morphology dilatation. Then, it proceeds to estimate the correct densities based on the estimations and to reduce the streak by a n adaptive three-dimensional filtering (106) whose parameters depend on the streak direction and the local image contrast.