基于多项式拟合的CT图像环状伪影校正  

A correction method for ring artifacts in CT image based on polynomial fitting

作　　者：魏英[1] 吴文晋[2] 杨民[2] 

机构地区：[1]北京信息科技大学自动化学院,北京100192 [2]北京航空航天大学机械工程及自动化学院,北京100191

出　　处：《北京信息科技大学学报（自然科学版）》2010年第4期45-48,共4页Journal of Beijing Information Science and Technology University

基　　金：北京市教育委员会科技发展计划面上项目(Km200910772009)

摘　　要：探测器探元的响应不一致性会使CT图像中出现环状伪影,环状伪影是影响CT图像像质的重要因素,影响图像的分析及后续处理。为此提出一种基于分段多项式拟合的环状伪影校正方法,该方法适用于单材质或图像中的材质衰减系数相差不大的情况。采用分段多项式拟合正弦图累加曲线得到修正因子,用修正因子修正不一致的探元,最后重建图像。实验结果证明此方法能有效抑制图像正中间部分环状伪影。Ring artifacts in computed tomography （CT） images are caused by in consistent pixel channel response of detector, As an important factor for quality of CT image, ring arifacts influenc the analysis and the post processing of image. A correction method based on piecewise polynomial fitting is proposed. This method is suited for workpeice which has only one material or when the attenuation coefficient of materials is nearly the same. First, the correction factors of each detector are got with the method of piecewise polynomial fitting, then the nonuniform pixel is correeted;lastly, the CT image is reconstructed. The feasibility of the method is validated by the experiment data.

关 键 词：环状伪影 CT 多项式拟合 

分 类 号：TP751[自动化与计算机技术—检测技术与自动化装置]