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Compressive near-field millimeter wave imaging algorithm based on Gini index and total variation mixed regularization
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作者 Jue Lyu Dong-Jie Bi +7 位作者 Bo Liu Guo Yi Xue-Peng Zheng Xi-Feng Li Li-Biao Peng Yong-Le Xie Yi-Ming Zhang Ying-Li Bai 《Journal of Electronic Science and Technology》 CAS CSCD 2023年第1期65-74,共10页
A compressive near-field millimeter wave(MMW)imaging algorithm is proposed.From the compressed sensing(CS)theory,the compressive near-field MMW imaging process can be considered to reconstruct an image from the under-... A compressive near-field millimeter wave(MMW)imaging algorithm is proposed.From the compressed sensing(CS)theory,the compressive near-field MMW imaging process can be considered to reconstruct an image from the under-sampled sparse data.The Gini index(GI)has been founded that it is the only sparsity measure that has all sparsity attributes that are called Robin Hood,Scaling,Rising Tide,Cloning,Bill Gates,and Babies.By combining the total variation(TV)operator,the GI-TV mixed regularization introduced compressive near-field MMW imaging model is proposed.In addition,the corresponding algorithm based on a primal-dual framework is also proposed.Experimental results demonstrate that the proposed GI-TV mixed regularization algorithm has superior convergence and stability performance compared with the widely used l1-TV mixed regularization algorithm. 展开更多
关键词 Millimeter wave(MMW) Compressed sensing(CS) Gini index(GI) Total variation(TV) Signal processing Image reconstruction
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图像重建中total variation正则化项的有限元计算方法
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作者 王彩芳 《计算机辅助工程》 2012年第3期49-52,56,共5页
为在迭代图像重建算法中获得更高质量的重建图像,推导出TV(Total Variation)正则化项关于重建图像的Fréchet导数,并给出该导数的有限元表示;利用两个数值实验,分别采用不同的网格尺寸和不同的形函数验证该有限元表示结果.数值实验... 为在迭代图像重建算法中获得更高质量的重建图像,推导出TV(Total Variation)正则化项关于重建图像的Fréchet导数,并给出该导数的有限元表示;利用两个数值实验,分别采用不同的网格尺寸和不同的形函数验证该有限元表示结果.数值实验结果表明:采用相同的k次单纯形元时,随着网格不断加密,计算结果的L1和L2误差均下降;采用相同的网格时,线性单纯形元函数计算结果明显优于分片常数有限元和二次单纯形元计算结果. 展开更多
关键词 图像重建 迭代算法 TOTAL variation正则化 Fréchet导数 单纯形元 有限元
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Image decomposition and staircase effect reduction based on total generalized variation 被引量:2
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作者 Jianlou Xu Xiangchu Feng +1 位作者 Yan Hao Yu Han 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第1期168-174,共7页
Total variation (TV) is widely applied in image process-ing. The assumption of TV is that an image consists of piecewise constants, however, it suffers from the so-cal ed staircase effect. In order to reduce the sta... Total variation (TV) is widely applied in image process-ing. The assumption of TV is that an image consists of piecewise constants, however, it suffers from the so-cal ed staircase effect. In order to reduce the staircase effect and preserve the edges when textures of image are extracted, a new image decomposition model is proposed in this paper. The proposed model is based on the to-tal generalized variation method which involves and balances the higher order of the structure. We also derive a numerical algorithm based on a primal-dual formulation that can be effectively imple-mented. Numerical experiments show that the proposed method can achieve a better trade-off between noise removal and texture extraction, while avoiding the staircase effect efficiently. 展开更多
关键词 total variation (TV) image decomposition staircaseeffect total generalized variation.
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Total Variation Constrained Non-Negative Matrix Factorization for Medical Image Registration 被引量:4
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作者 Chengcai Leng Hai Zhang +2 位作者 Guorong Cai Zhen Chen Anup Basu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第5期1025-1037,共13页
This paper presents a novel medical image registration algorithm named total variation constrained graphregularization for non-negative matrix factorization(TV-GNMF).The method utilizes non-negative matrix factorizati... This paper presents a novel medical image registration algorithm named total variation constrained graphregularization for non-negative matrix factorization(TV-GNMF).The method utilizes non-negative matrix factorization by total variation constraint and graph regularization.The main contributions of our work are the following.First,total variation is incorporated into NMF to control the diffusion speed.The purpose is to denoise in smooth regions and preserve features or details of the data in edge regions by using a diffusion coefficient based on gradient information.Second,we add graph regularization into NMF to reveal intrinsic geometry and structure information of features to enhance the discrimination power.Third,the multiplicative update rules and proof of convergence of the TV-GNMF algorithm are given.Experiments conducted on datasets show that the proposed TV-GNMF method outperforms other state-of-the-art algorithms. 展开更多
关键词 Data clustering dimension reduction image registration non-negative matrix factorization(NMF) total variation(TV)
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Dark channel prior based blurred image restoration method using total variation and morphology 被引量:1
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作者 Yibing Li Qiang Fu +1 位作者 Fang Ye Hayaru Shouno 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第2期359-366,共8页
The blurred image restoration method can dramatically highlight the image details and enhance the global contrast, which is of benefit to improvement of the visual effect during practical ap- plications. This paper is... The blurred image restoration method can dramatically highlight the image details and enhance the global contrast, which is of benefit to improvement of the visual effect during practical ap- plications. This paper is based on the dark channel prior principle and aims at the prior information absent blurred image degradation situation. A lot of improvements have been made to estimate the transmission map of blurred images. Since the dark channel prior principle can effectively restore the blurred image at the cost of a large amount of computation, the total variation (TV) and image morphology transform (specifically top-hat transform and bottom- hat transform) have been introduced into the improved method. Compared with original transmission map estimation methods, the proposed method features both simplicity and accuracy. The es- timated transmission map together with the element can restore the image. Simulation results show that this method could inhibit the ill-posed problem during image restoration, meanwhile it can greatly improve the image quality and definition. 展开更多
关键词 image restoration dark channel prior total variation (TV) morphology transform
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Novel image restoration model coupling gradient fidelity term based on adaptive total variation 被引量:1
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作者 石明珠 许廷发 +3 位作者 梁炯 冯亮 张坤 周立伟 《Journal of Beijing Institute of Technology》 EI CAS 2011年第2期261-266,共6页
A novel image restoration model coupling with a gradient fidelity term based on adaptive total variation is proposed in this paper. In order to choose proper parameters, the selection criteria were analyzed theoretica... A novel image restoration model coupling with a gradient fidelity term based on adaptive total variation is proposed in this paper. In order to choose proper parameters, the selection criteria were analyzed theoretically, and a simple scheme to demonstrate its validity was adopted experimentally. To make fair comparisons of performances of three models, the same numerical algorithm was used to solve partial differential equations. Both the international standard test image on Lena and HR image of CBERS-02B of Dalian city were used to verify the performance of the model. Experimental results illustrate that the new model not only preserved the edge and important details but also alleviated the staircase effect effectively. 展开更多
关键词 image restoration total variation(TV) gradient fidelity term staircase effect
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Adaptive Parameter Selection for Total Variation Image Deconvolution 被引量:3
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作者 You-Wei Wen Andy M. Yip 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2009年第4期427-438,共12页
In this paper,we propose a discrepancy rule-based method to automatically choose the regularization parameters for total variation image restoration problems. The regularization parameters are adjusted dynamically in ... In this paper,we propose a discrepancy rule-based method to automatically choose the regularization parameters for total variation image restoration problems. The regularization parameters are adjusted dynamically in each iteration.Numerical results are shown to illustrate the performance of the proposed method. 展开更多
关键词 参数选择 解卷积 差图像 自适应 图像恢复 自动选择 动态调整 数值结果
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Multiquadric Radial Basis Function Approximation Scheme for Solution of Total Variation Based Multiplicative Noise Removal Model 被引量:1
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作者 Mushtaq Ahmad Khan Ahmed BAltamimi +4 位作者 Zawar Hussain Khan Khurram Shehzad Khattak Sahib Khan Asmat Ullah Murtaza Ali 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第1期55-88,共34页
This article introduces a fastmeshless algorithm for the numerical solution nonlinear partial differential equations(PDE)by Radial Basis Functions(RBFs)approximation connected with the Total Variation(TV)-basedminimiz... This article introduces a fastmeshless algorithm for the numerical solution nonlinear partial differential equations(PDE)by Radial Basis Functions(RBFs)approximation connected with the Total Variation(TV)-basedminimization functional and to show its application to image denoising containing multiplicative noise.These capabilities used within the proposed algorithm have not only the quality of image denoising,edge preservation but also the property of minimization of staircase effect which results in blocky effects in the images.It is worth mentioning that the recommended method can be easily employed for nonlinear problems due to the lack of dependence on a mesh or integration procedure.The numerical investigations and corresponding examples prove the effectiveness of the recommended algorithm regarding the robustness and visual improvement as well as peak-signal-to-noise ratio(PSNR),signal-to-noise ratio(SNR),and structural similarity index(SSIM)corresponded to the current conventional TV-based schemes. 展开更多
关键词 Denoised image multiplicative and speckle noises total variation(TV)filter Euler-Lagrange restoration equation multiquadric radial basis functions meshless and mesh-based schemes
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Box-constrained Total-variation Image Restoration with Automatic Parameter Estimation 被引量:1
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作者 HE Chuan HU Chang-Hua ZHANG Wei SHI Biao 《自动化学报》 EI CSCD 北大核心 2014年第8期1804-1811,共8页
关键词 图像复原 参数估计 变差 图像恢复 动态范围 最小化问题 正则化参数 TM图像
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A Hybrid Regularization-Based Multi-Frame Super-Resolution Using Bayesian Framework
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作者 Mahmoud M.Khattab Akram M.Zeki +3 位作者 Ali A.Alwan Belgacem Bouallegue Safaa S.Matter Abdelmoty M.Ahmed 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期35-54,共20页
The prime purpose for the image reconstruction of a multi-frame super-resolution is to reconstruct a higher-resolution image through incorporating the knowledge obtained from a series of relevant low-resolution images... The prime purpose for the image reconstruction of a multi-frame super-resolution is to reconstruct a higher-resolution image through incorporating the knowledge obtained from a series of relevant low-resolution images,which is useful in numerousfields.Nevertheless,super-resolution image reconstruction methods are usually damaged by undesirable restorative artifacts,which include blurring distortion,noises,and stair-casing effects.Consequently,it is always challenging to achieve balancing between image smoothness and preservation of the edges inside the image.In this research work,we seek to increase the effectiveness of multi-frame super-resolution image reconstruction by increasing the visual information and improving the automated machine perception,which improves human analysis and interpretation processes.Accordingly,we propose a new approach to the image reconstruction of multi-frame super-resolution,so that it is created through the use of the regularization framework.In the proposed approach,the bilateral edge preserving and bilateral total variation regularizations are employed to approximate a high-resolution image generated from a sequence of corresponding images with low-resolution to protect significant features of an image,including sharp image edges and texture details while preventing artifacts.The experimental results of the synthesized image demonstrate that the new proposed approach has improved efficacy both visually and numerically more than other approaches. 展开更多
关键词 SUPER-RESOLUTION regularized framework bilateral total variation bilateral edge preserving
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稀疏角度CT图像重建的Huber-TV正则化方法
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作者 李维 张本鑫 《现代电子技术》 2023年第2期65-69,共5页
对于稀疏角度下的投影数据,计算机断层扫描重建图像容易出现分辨率低、伪影较多的问题,难以满足工业及医学诊断要求。文中从迭代重建的角度出发,提出一个结合全变分(TV)和Huber函数(Huber-TV)的CT重建方法。该方法利用Huber函数替代传... 对于稀疏角度下的投影数据,计算机断层扫描重建图像容易出现分辨率低、伪影较多的问题,难以满足工业及医学诊断要求。文中从迭代重建的角度出发,提出一个结合全变分(TV)和Huber函数(Huber-TV)的CT重建方法。该方法利用Huber函数替代传统全变分模型中的L1范数,在合理控制函数阈值的条件下,充分利用Huber函数的线性部分对大于阈值的梯度图像进行较轻的惩罚,以保持图像边缘连续性;再结合二次项对小于阈值的梯度图像进行较大的惩罚,以抑制图像中不连续梯度跳跃。新模型目标函数的光滑性可以使得梯度下降法快速收敛到最优值,避开传统全变分模型中的次梯度计算,从而降低计算复杂度并加快迭代速度。实验结果表明,在稀疏角度重建条件下,与传统TV模型相比,Huber-TV模型的均方根误差降低19%,信噪比提升22.33 dB,说明所提方法高效可行。 展开更多
关键词 CT图像重建 梯度图像 全变分模型 Huber-TV 图像处理 数据分析
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一种基于稀疏重构的多视角MIMO雷达关联成像算法研究
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作者 张弓 田雨薇 +1 位作者 袁家雯 张宇 《系统工程与电子技术》 EI CSCD 北大核心 2024年第2期470-477,共8页
为改善复杂目标的成像表现、提升雷达图像的视觉效果,提出一种基于稀疏重构的多视角多输入多输出(multiple input multiple output,MIMO)雷达关联成像方法,设计了多视角雷达散射面积(radar cross section,RCS)起伏的稀疏重构关联成像模... 为改善复杂目标的成像表现、提升雷达图像的视觉效果,提出一种基于稀疏重构的多视角多输入多输出(multiple input multiple output,MIMO)雷达关联成像方法,设计了多视角雷达散射面积(radar cross section,RCS)起伏的稀疏重构关联成像模型。所提算法能提高辐射场信号随机性,改善复杂目标雷达关联成像参考信号与回波之间相关性退化的情况,减小多视角RCS起伏对相关性的影响,提升多视角下的关联成像质量。最后,通过仿真验证了所提方法的有效性。 展开更多
关键词 雷达成像 多输入多输出 雷达关联成像 正则化 全变差
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基于两步迭代TV正则化的电阻抗图像重建算法 被引量:25
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作者 范文茹 王化祥 郝魁红 《仪器仪表学报》 EI CAS CSCD 北大核心 2012年第3期625-630,共6页
针对电阻抗层析成像(electrical impedance tomography,EIT)逆问题求解的欠定性和病态性,克服传统基于L2范数的Tikhonov正则化对介质边界的模糊效应,提出一种基于两步迭代的正则化图像重建算法。该算法采用具有良好保边性的总变差(total... 针对电阻抗层析成像(electrical impedance tomography,EIT)逆问题求解的欠定性和病态性,克服传统基于L2范数的Tikhonov正则化对介质边界的模糊效应,提出一种基于两步迭代的正则化图像重建算法。该算法采用具有良好保边性的总变差(total variation,TV)正则化函数,利用两步迭代法引入TV去噪算子,达到解的双重正则化效果。与传统最小二乘迭代算法、TV相关迭代算法相比,不仅保证了逆问题求解的稳定性,而且进一步提高了非连续分布介质区域成像的分辨能力,具有较好的成像精度。 展开更多
关键词 电阻抗层析成像 TV正则化 逆问题
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基于TV模型的改进算法在图像修复中的应用 被引量:5
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作者 许云云 朱晓临 +1 位作者 黄淑兵 朱坤 《合肥工业大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第12期1916-1920,共5页
基于TV(total variation)模型的修复算法有较好的恢复效果,但对参数的选取比较敏感,且运算量大。文章提出了基于TV模型的改进的自适应算法,可根据破损区域外部参考像素对待修补点的相关度,通过设置不同的参数和权值,将不同形状的待修复... 基于TV(total variation)模型的修复算法有较好的恢复效果,但对参数的选取比较敏感,且运算量大。文章提出了基于TV模型的改进的自适应算法,可根据破损区域外部参考像素对待修补点的相关度,通过设置不同的参数和权值,将不同形状的待修复区域所用的不同算法统一表示,使其应用范围更广、速度更快;此外,在迭代过程中,设置不同的参数以解决参数选取的敏感问题,从而达到更好的修复效果。实验表明,该算法能高效、稳定地处理破损区域的图像信息。 展开更多
关键词 整体变分 图像修复 统一表达式 自适应
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综合自适应阈值与多尺度的TV图像修复方法 被引量:3
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作者 屈磊 韦穗 +1 位作者 梁栋 王年 《计算机工程》 CAS CSCD 北大核心 2007年第22期18-20,共3页
基于TV模型的图像修复算法具有较好的修复效果,但其对参数的选取较敏感,且运算量较大。该文提出了一种综合自适应阈值与多尺度的TV图像修复算法,该方法不仅可以提高TV图像修复模型的修复稳定性,还可以进一步压缩运算量,提高修复速度。
关键词 图像修复 总变分(TV) 自适应阈值 多尺度
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改进TV复原模型的彩色-灰度图像变换方法 被引量:4
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作者 郭彦伶 彭进业 王大凯 《计算机工程与应用》 CSCD 北大核心 2009年第7期192-194,共3页
针对彩色图像到灰度图像的变换这一问题,提出了一种新的基于TV(全变分)复原模型的新方法。利用Sapiro等所提出的矢量图像的水平集概念,结合全变分复原,建立新的变换模型,实现算法。实验表明,所提方法实现的彩色一灰度图像变换,不仅很好... 针对彩色图像到灰度图像的变换这一问题,提出了一种新的基于TV(全变分)复原模型的新方法。利用Sapiro等所提出的矢量图像的水平集概念,结合全变分复原,建立新的变换模型,实现算法。实验表明,所提方法实现的彩色一灰度图像变换,不仅很好地解决了原来传统变换不能保持形状的问题,并且能解决Sapiro等所提出方法的边缘模糊化缺点,使变换后图像的边缘锐利程度得到了较大的提高。 展开更多
关键词 图像变换 全变分 保持形状 边缘锐度
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基于自适应中值滤波器和TV修复的椒盐噪声去除(英文) 被引量:3
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作者 王超 叶中付 《中国科学技术大学学报》 CAS CSCD 北大核心 2008年第3期282-287,共6页
提出一种两步式椒盐噪声去除方法.第一步利用自适应中值滤波器来识别出被噪声污染的候选点;第二步利用一种边缘保持技术(全变差图像修复)来恢复出被噪声污染的点.由于椒盐噪声点的灰度值和原始像素灰度独立,所以在采用恢复技术时不使用... 提出一种两步式椒盐噪声去除方法.第一步利用自适应中值滤波器来识别出被噪声污染的候选点;第二步利用一种边缘保持技术(全变差图像修复)来恢复出被噪声污染的点.由于椒盐噪声点的灰度值和原始像素灰度独立,所以在采用恢复技术时不使用噪声点自身的灰度信息.在噪声率不很高的情况下,这种方法可以获得比现有最好方法更高的信噪比;当噪声率高达70%以上时,该方法的信噪比与现有方法非常接近,但是主观视觉效果(例如边缘保持能力)更佳. 展开更多
关键词 椒盐噪声 自适应中值滤波器 图像去噪 图像修复 全变差
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基于TV与SSIM的图像质量评价方法 被引量:2
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作者 庞璐璐 李从利 罗军 《计算机工程》 CAS CSCD 2012年第3期215-217,共3页
提出一种基于全变分(TV)模型与结构相似度(SSIM)的图像质量评价方法。对待评价图像进行主动定量加噪,得到降质图像,利用自适应的TV去噪模型得到消噪图像,采用SSIM方法对待评价图像与消噪图像进行全参考评价,得到待评价图像的无参考评价... 提出一种基于全变分(TV)模型与结构相似度(SSIM)的图像质量评价方法。对待评价图像进行主动定量加噪,得到降质图像,利用自适应的TV去噪模型得到消噪图像,采用SSIM方法对待评价图像与消噪图像进行全参考评价,得到待评价图像的无参考评价指标。采用标准测试图像和LIVE库的降质图像进行实验,结果表明,该方法可在无参考图像的条件下对图像质量进行评估,评价结果与主观评价结果具有较高的一致性。 展开更多
关键词 图像质量评价 全变分 结构相似度 人眼视觉系统 图像去噪
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自适应Snake-TV模型在彩色图像修复中的应用 被引量:1
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作者 朱晓临 许云云 李震宇 《合肥工业大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第11期1655-1660,共6页
文章在整体变分模型(TV)的基础上引入蛇(Snake)模型,同时考虑待修复区域的形状,提出了自适应Snake-TV模型,并将其应用到灰度图像和彩色图像的修复,该模型能很好地保持图像的视觉连通性。试验结果表明:该算法在迭代次数相同的条件下修复... 文章在整体变分模型(TV)的基础上引入蛇(Snake)模型,同时考虑待修复区域的形状,提出了自适应Snake-TV模型,并将其应用到灰度图像和彩色图像的修复,该模型能很好地保持图像的视觉连通性。试验结果表明:该算法在迭代次数相同的条件下修复彩色图像的效果比TV模型好得多;与Snake-CDD模型相比,修复效果更好,同时所用时间也大大减少。 展开更多
关键词 彩色图像修复 整体变分 区域形状 蛇模型 图像增强项
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TV正则化的双迭代RL湍流退化图像复原算法 被引量:2
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作者 王锋 张昆帆 +1 位作者 王希云 赵拥军 《信息工程大学学报》 2014年第2期210-214,共5页
RL算法是湍流退化图像复原的一类重要算法,但在迭代过程中存在噪声放大或过度平滑问题。围绕湍流退化图像复原问题对RL(Richardson-Lucy)算法及其改进方法进行研究:建立了一种短曝光成像探测湍流退化模型,并给出该模型中随机相位屏的数... RL算法是湍流退化图像复原的一类重要算法,但在迭代过程中存在噪声放大或过度平滑问题。围绕湍流退化图像复原问题对RL(Richardson-Lucy)算法及其改进方法进行研究:建立了一种短曝光成像探测湍流退化模型,并给出该模型中随机相位屏的数值模拟方法;推导了RL算法的基本原理和计算公式;为更好地从湍流退化图像中恢复目标,提出了TV正则化双迭代RL图像复原算法。改进算法引入总体变分约束,并对目标图像和点扩展函数采用内外循环双重迭代,充分利用了目标图像和点扩展函数的内在联系。仿真实验表明,算法能有效地保持了图像的细节信息,复原效果明显优于传统RL算法。 展开更多
关键词 湍流退化模型 图像复原 RL算法 点扩展函数 总体变分 正则化
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