Due to the beam-hardening effect of the broad energy spectrum of the X-ray source in computed tomography, the reconstructed images usually suffer from severe artifacts when metallic objects are being imaged. Metal artifact correction methods are usually sophisticated and not practical, especially in some non-medical applications, in which the linear attenuation coefficients are unknown. This paper suggests a simple and effective algorithm to estimate the unreliable measurements. The proposed algorithm is an iterative algorithm, in which the iteration is performed in the projection domain, while the objective function is set up in the image domain. The final image is reconstructed with the conventional filtered backprojection algorithm. The feasibility of the proposed method is verified with airport bags that contain some unknown metals.

中文翻译：

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投影域迭代以估计不可靠的测量值。

由于在计算机断层摄影中X射线源的宽能谱具有束硬化作用，因此在对金属物体成像时，重建的图像通常会遭受严重的伪影。金属伪影校正方法通常是复杂且不实用的，尤其是在某些线性衰减系数未知的非医学应用中。本文提出了一种简单有效的算法来估计不可靠的测量值。所提出的算法是一种迭代算法，其中在投影域中执行迭代，而在图像域中建立目标函数。使用常规的滤波反投影算法重建最终图像。装有某些未知金属的机场行李袋证明了该方法的可行性。