摘要
稀疏角度投影数据重建CT图像,是一种有效的降低X射线辐射剂量的方式。提出一种改进的平滑硬阈值(SHT)约束,使其更接近于L_0范数,同时最优参数不受重建图像影响。该重建算法沿用ART-TV的重建策略,即对每次ART重建后的图像进行改进SHT的最小化约束。实验表明:新算法提高了重建图像质量,信噪比更高,平均绝对误差更小。
Image reconstruction for sparse view computed tomography is an effective way to reduce x - ray radia- tion. A modified SHT has been proposed for sparse - view CT image reconstruction. The improved SHT is much closer to L0 norm than SHT. The parameter in modified SHT is not affected by reconstructed image. Similar to ART- TV reconstruction strategy, our method in this study includes ART reconstruction followed by improved SHT minimization. Experimental results have demonstrated that new method can lead to images with better qual- ity, higher signal - to - noise ratio and lower mean absolute error.
出处
《核电子学与探测技术》
CAS
北大核心
2015年第9期940-943,共4页
Nuclear Electronics & Detection Technology
基金
国家科技支撑计划课题(2015BAI01B10)资助
关键词
稀疏角度
CT图像
迭代重建
平滑硬阈值
L0范数
sparse views
CT image
iterative reconstruction
smooth hard threshold
Lo norm
