【作者】 景越峰； 刘军； 管永红；

【Author】 JING Yuefeng~(1)),LIU Jun~(2)),GUAN Yonghong~(3)) (Institute of Fluid Physics,CAEP,P.O.Box 919-105 Mianyang 621900,China)

【机构】 中国工程物理研究院流体物理研究所；

【摘要】 针对闪光照相图像信噪比低的特点,提出了一种改进的约束共轭梯度闪光照相图像重建算法。该算法在约束共轭梯度(CCG)迭代重建的基础上,提出了一种新的预优方法,有效减小了重建图像的轴线噪声,利用松弛迭代技术代替共轭梯度法中一维最优迭代步长,并提出了新的收敛准则,在保证算法收敛的同时,有效减少了重建算法的计算量。数值试验表明,与传统约束共轭梯度重建算法相比,改进算法稳定收敛,迭代速度更快,并能有效提高重建质量。更多还原

【Abstract】 According to the characteristics of flash radiographic image with low signal-to-noise,an improved constrained conjugate gradient reconstruction algorithm is proposed.New preconditioned method is consummated which can more accurately reconstruct image’s axis of symmetry.The new stop criterion and the substitution of relaxation step for optimal step in the one-dimension search are adopted to ensure the reconstruction accuracy and shorten the reconstruction time simultaneously.The numerical experiment results show that the improved algorithm has better general performance in speeding the iteration time and reconstruction quality compared with the constrained conjugate gradient algorithm.更多还原