CASIA OpenIR  > 毕业生  > 博士学位论文
气动光学效应图像复原算法与应用研究
其他题名Research of Image Restoration Algorithms and Applications in Aero-Optic Effect
赵博
2012-05-30
学位类型工学博士
中文摘要超声速飞行器特别是高超声速飞行器的发展是一个国家国防实力的重要体现,因此,发达国家投入大量的物力和财力开展超声速飞行器的研究。超声速飞行器进入大气层高速飞行的过程中,光学头罩与高速气流发生剧烈的相互作用,引起气动光学效应,导致飞行器成像系统获取的图像产生了严重的模糊、畸变与偏移现象,极大的影响了飞行器对目标的检测、识别、跟踪与精确打击能力。因此,迫切需要研究气动光学效应图像复原理论与方法,其中气动光学效应引起的模糊图像的复原是一个亟待解决的难题。本文选择以超声速飞行器为背景,开展模糊图像复原算法与应用研究。 模糊图像的复原是数学物理中的“反问题”,由于其病态特性,在理论上和实践中都存在很多困难。本文在深入分析国内外学者研究成果的基础上,开展对图像去模糊问题的研究。首先,针对Richardson-Lucy算法的振铃效应与噪声放大的缺点,提出了一种引入增益图的图像去模糊新算法,抑制了迭代过程中振铃效应的传播,避免噪声的进一步放大。其次,针对图像去模糊问题的病态特性,提出了一种基于非局部范围马尔科夫随机场先验约束的Bayesian去模糊算法,可以同时捕获图像局部细节信息和相邻块的结构信息。最后,为了避免基于最大后验估计去模糊方法的缺陷,提出了基于最小均方误差估计的图像去模糊算法,把图像去模糊与噪声估计融合在一个框架下,避免了使用额外的噪声估计步骤或者提前指定正则化参数。此外,通过算法移植与优化,去模糊算法在基于TI公司DM6467的嵌入式原型系统中得到了初步验证。 本文的主要工作和贡献如下: (1)提出了一种基于Richardson-Lucy(RL)的图像去模糊新算法。通过分析RL算法振铃效应产生的原因,在迭代过程中引入了增益图,减少了图像平坦区域的振铃效应,并能保留图像细节信息,对于图像噪声也有明显的抑制作用。实验表明,新算法与传统RL算法相比较,峰值信噪比值平均提高了10%,同时保留了RL算法效率高、计算速度快等优点。 (2)提出了一种基于非局部范围马尔科夫随机场先验约束的Bayesian去模糊算法。该算法能够同时捕获图像局部块的细节信息和相邻块的相似信息,能够复原出更多的图像细节。实验表明,引入新先验的去模糊算法可以有效的复原取自不同领域的模糊图像。 (3)提出了一种基于最小均方误差估计的图像去模糊新算法。针对基于最大后验估计的图像去模糊算法存在的缺陷,该算法把图像去模糊问题和噪声估计问题在统一的框架下进行,避免使用额外的噪声估计步骤或者提前指定正则化参数。本文使用辅助变量Gibbs采样算法计算最小均方误差估计,同时,算法自然地结合了非局部范围马尔科夫随机场先验知识约束问题的求解。实验表明,该算法可以有效的复原出丢失的图像细节信息,同时阻止了振铃效应的传播。 (4)在应用方面,通过算法移植和优化,把图像复原算法移植到基于TI公司的DM6467的嵌入式原型系统中,初步验证算法的有效性。
英文摘要The development of supersonic especially hypersonic aircraft is an important reflection of the national defense strength. Therefore, the developed countries have invested a large amount of materials and financial resources to carry out the research on supersonic aircraft. While supersonic aircraft flying into the atmosphere with high speed, drastic interaction occurs between the vehicles’ optical hood and the high-speed airflow, thereby causing the aero-optical effects. As a result, the images received by the imaging system on the aircraft are blurring, distortion or shifting, which seriously affect the capability of aircraft for target detecting, recognition, tracking and precise attacking. Consequently, it is urgently need to study the image restoration theory and methods caused by the aero-optical effects. Among all, the blurring image restoration is a pressing difficult problem. Based on the supersonic aircraft, the paper carries out researching of restoration algorithms and its application of blurring image. The restoration of blurring image is the "inverse problem" in mathematics physics which is tough in theory and practice because of ill-posedness. Based on analyzing the research results of scholars at home and abroad in depth, the deblurring problem is studied in the paper. Firstly, aiming at overcoming the shortcomings of the Richardson-Lucy (RL) algorithm, that is, ringing artifacts and noise amplification, a new image deblurring algorithm is proposed by introducing Gain-Map, which avoids the spreading of ringing artifacts and further amplification of the image noise during iteration. Secondly, to solve the ill-posedness of the deblurring problem, Bayesian deblurring algorithm based on the Non-Local Range Markov Random Field (NLR-MRF) prior constraint is proposed, which can capture the local image details while acquiring structural information among adjacent blocks . Finally, to avoid the defects of the maximum a posteriori (MAP), a new deblurring algorithm based on minimum mean square error (MMSE) estimation is proposed. The new algorithm performs image deblurring and noise estimation in a unified framework which prevents additional noise estimation step or specifies the regularization parameter beforehand. In addition, through algorithm transplantation and optimization, the deblurring algorithm has been verified embedded prototype systems based on DM6467 from TI company. The main work and contributions are as follows: (1) A novel image d...
关键词气动光学效应 图像去模糊 Rl算法 Nlr-mrf Mmse估计 Aero-optical Effects Image Deblurring Richardson-lucy Algorithm Nlr-mrf Mmse Estimation
语种中文
文献类型学位论文
条目标识符http://ir.ia.ac.cn/handle/173211/6451
专题毕业生_博士学位论文
推荐引用方式
GB/T 7714
赵博. 气动光学效应图像复原算法与应用研究[D]. 中国科学院自动化研究所. 中国科学院研究生院,2012.
条目包含的文件
文件名称/大小 文献类型 版本类型 开放类型 使用许可
CASIA_20091801462807(5201KB) 暂不开放CC BY-NC-SA
个性服务
推荐该条目
保存到收藏夹
查看访问统计
导出为Endnote文件
谷歌学术
谷歌学术中相似的文章
[赵博]的文章
百度学术
百度学术中相似的文章
[赵博]的文章
必应学术
必应学术中相似的文章
[赵博]的文章
相关权益政策
暂无数据
收藏/分享
所有评论 (0)
暂无评论
 

除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。