基于变加速广义交替投影的CUP-VISAR压缩图像反演算法  

CUP-VISAR Compressed Image Inversion Algorithm Based on Variable-Accelerated Generalized Alternating Projection

作　　者：黄庆鑫 李海艳[1] 甘华权 郑铠涛 余远平 黄运保[1] Huang Qingxin;Li Haiyan*;Gan Huaquan;Zheng Kaitao;Yu Yuanping;Huang Yunbao(School of Electromechanical Engineering,Guangdong University of Technology,Guangzhou 510006,Guangdong,China)

机构地区：[1]广东工业大学机电工程学院,广东广州510006

出　　处：《光学学报》2023年第21期103-111,共9页Acta Optica Sinica

基　　金：国家自然科学基金(12127810,51975125,12105269)。

摘　　要：针对从基于压缩超快成像的瞬态冲击波二维诊断系统获得的压缩图像中反演出时变冲击波二维条纹的问题,提出一种基于变加速广义交替投影的图像反演算法。该算法利用二维条纹图像所具有的强低秩性和梯度稀疏特性,将问题转化为基于低秩与全变分双先验约束的优化问题,并通过变加速的方式有效减少了广义交替投影框架迭代求解该问题过程中产生的误差累积。仿真结果表明:与现有算法相比,在无噪情况下,所提算法的平均峰值信噪比提升了11.0 dB,平均结构相似性提升了11.4百分点;在含噪情况下,所提算法反演效果稳定,抗噪能力良好。最后,实验结果表明,所提算法针对实际压缩图像也能反演出轮廓清晰的二维冲击波条纹,且一维冲击波速度的最大相对误差从20.38%下降到11.66%,降低了8.72百分点,验证了该算法的可行性。Objective The diagnosis technology of laser-driven inertial confinement fusion(ICF)is an essential research direction to promote the development of controllable nuclear fusion.Specifically,the velocity interferometer system for any reflector(VISAR)is the most extensively employed diagnostic device of ICF,and it is adopted to record one-dimensional wavefront information with picosecond time resolution generated by ICF.However,the information is only confined to the velocity changes of a line on the target surface and cannot provide two-dimensional(2D)velocity field information of all locations on the target surface.A new type of 2D-VISAR diagnosis system is obtained by combining the compressed ultra-fast photography(CUP)system which can implement 2D ultra-fast imaging with line-VISAR and is applied to ICF diagnosis.The compressed 2D images with high time resolution are obtained,and the 2D stripes of time-varying shock waves are obtained by the inversion algorithm.However,the current mainstream inversion algorithms are readily affected by their regularization parameters,with unstable imaging effects.Therefore,we propose a compressed image inversion algorithm based on variable-accelerated generalized alternating projection(GAP)to optimize the CUP-VISAR inversion effect.Methods We put forward a novel CUP-VISAR compressed image inversion algorithm.First,considering the strong low-rank and gradient sparsity characteristics of 2D fringe images,low rank(LR)regularization and total variation(TV)regularization are employed as the prior information of image processing,and the problem is transformed into an optimization problem based on double prior constraints of LR and TV.The GAP algorithm is utilized as an iterative solution framework to decompose the objective optimization problem into two sub-problems,and TV and LR are extended to the sub-problems respectively to give full expression to the synergistic effect of double prior constraints.Finally,considering the influence of error accumulation in iterative GAP under chaot

关 键 词：惯性约束聚变 成像型任意反射面速度干涉仪 压缩超快成像 广义交替投影 图像反演 低秩约束 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]