| 摘要: |
| 为了复原缺乏先验知识的降质图像以及探索层析X射线图像重构的新途径,借鉴Spall 和Cristion的随机扰动近似(SPSA)方法,将其扩展到高阶和多元的情形,进而提出了一种新的随机扰动梯度近似算法.此算法无须先验知识或后验概率,具有良好的稳定收敛性.对比实验表明,将此算法用于图像的复原和重构可获得良好的效果,而且性能稳定. |
| 关键词: 图像重构 层析X射线摄影法 L混合过程 图像复原 随机扰动梯度 |
| DOI： |
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| 基金项目:国家重点基础研究发展规划973资助项目(G1998030600);福建省自然科学基金资助项目(F00013) |
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| An Image Restoration and Reconstruction Algorithm Based on Stochastic Perturbati on Gradient Approximation |
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LIU Chuan-cai,FU Qing-xiang
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| Abstract: |
| In order to restore degenerative images, which are go short of priori knowledge about original images, and explore new ways of x-ray tomographic image reconstruction, the experience of Spall and Cristion抯 simultaneous perturbation stochastic approximation (SPSA) method is drawn on, and this algorithm is extended to the high order and multivariate case, then a new gradient approximation algorithm with stochastic perturbation is presented. This algorithm does not need either a priori knowledge or a posteriori probability, and has convergence with excellent stability. Comparative experiments show that this algorithm converges to visually good images with excellent stability for restoration and reconstruction of images. |
| Key words: image reconstruction x-ray tomography L-mixing processe image restoration stochastic perturbation gradient |
