该论文通过将基于定向准分析小波包(QWP)与最新的加权核定标准最小化(WNNM)denoising算法相结合,从而提出了图像降级方案。基于QWP的Denoising方法(QWPDN)由降级图像的多尺度QWP变换,使用双变量收缩方法的适应性局部软阈值应用于转换系数,以及从几个分解级别中恢复阈值系数的图像。合并的方法由QWPDN和WNNM算法的几个迭代组成,以每种迭代的方式,从一种算法中的输出将输入提高到另一个算法。提出的方法将QWPDN的功能融合在一起,即使在严重损坏的图像中捕获边缘和精细的纹理模式,并利用了WNNM算法固有的真实图像中的非本地自相似性。多个实验将所提出的方法与包括WNNM在内的六种高级denoing算法进行了比较,证实,在定量度量和视觉感知质量方面,合并的跨增强算法比大多数都优于大多数。
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We propose a novel image denoising strategy based on an enhanced sparse representation in transform domain. The enhancement of the sparsity is achieved by grouping similar 2-D image fragments (e.g., blocks) into 3-D data arrays which we call "groups." Collaborative filtering is a special procedure developed to deal with these 3-D groups. We realize it using the three successive steps: 3-D transformation of a group, shrinkage of the transform spectrum, and inverse 3-D transformation. The result is a 3-D estimate that consists of the jointly filtered grouped image blocks. By attenuating the noise, the collaborative filtering reveals even the finest details shared by grouped blocks and, at the same time, it preserves the essential unique features of each individual block. The filtered blocks are then returned to their original positions. Because these blocks are overlapping, for each pixel, we obtain many different estimates which need to be combined. Aggregation is a particular averaging procedure which is exploited to take advantage of this redundancy. A significant improvement is obtained by a specially developed collaborative Wiener filtering. An algorithm based on this novel denoising strategy and its efficient implementation are presented in full detail; an extension to color-image denoising is also developed. The experimental results demonstrate that this computationally scalable algorithm achieves state-of-the-art denoising performance in terms of both peak signal-to-noise ratio and subjective visual quality.
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Tensor robust principal component analysis (TRPCA) is a promising way for low-rank tensor recovery, which minimizes the convex surrogate of tensor rank by shrinking each tensor singular values equally. However, for real-world visual data, large singular values represent more signifiant information than small singular values. In this paper, we propose a nonconvex TRPCA (N-TRPCA) model based on the tensor adjustable logarithmic norm. Unlike TRPCA, our N-TRPCA can adaptively shrink small singular values more and shrink large singular values less. In addition, TRPCA assumes that the whole data tensor is of low rank. This assumption is hardly satisfied in practice for natural visual data, restricting the capability of TRPCA to recover the edges and texture details from noisy images and videos. To this end, we integrate nonlocal self-similarity into N-TRPCA, and further develop a nonconvex and nonlocal TRPCA (NN-TRPCA) model. Specifically, similar nonlocal patches are grouped as a tensor and then each group tensor is recovered by our N-TRPCA. Since the patches in one group are highly correlated, all group tensors have strong low-rank property, leading to an improvement of recovery performance. Experimental results demonstrate that the proposed NN-TRPCA outperforms some existing TRPCA methods in visual data recovery. The demo code is available at https://github.com/qguo2010/NN-TRPCA.
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实际图像的稀疏表示是成像应用的非常有效的方法,例如去噪。近年来,随着计算能力的增长,利用一个或多个图像提取的补丁内冗余的数据驱动策略,以增加稀疏性变得更加突出。本文提出了一种新颖的图像去噪算法,利用了由量子多体理论的图像依赖性的基础。基于补丁分析,通过类似于量子力学的术语来形式化局部图像邻域中的相似度测量,可以有效地保留真实图像的局部结构的量子力学中的相互作用。这种自适应基础的多功能性质将其应用范围扩展到图像无关或图像相关的噪声场景,而无需任何调整。我们对当代方法进行严格的比较,以证明所提出的算法的去噪能力,无论图像特征,噪声统计和强度如何。我们说明了超参数的特性及其对去噪性能的各自影响,以及自动化规则,可以在实验设置中选择其值的自动化规则,其实际设置不可用。最后,我们展示了我们对诸如医用超声图像检测应用等实际图像的方法处理实际图像的能力。
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本文的目的是描述一种从贝叶斯推理的观点来描述一种新的非参数降噪技术,其可以自动提高一个和二维数据的信噪比,例如例如,例如,天文图像和光谱。该算法迭代地评估数据的可能的平滑版本,平滑模型,获得与嘈杂测量统计上兼容的底层信号的估计。迭代基于最后一个顺利模型的证据和$ \ Chi ^ 2 $统计数据,并且我们将信号的预期值计算为整个平滑模型的加权平均值。在本文中,我们解释了算法的数学形式主义和数值实现,我们在利用真正的天文观测的电池对峰值信号,结构相似性指数和时间有效载荷来评估其性能。我们完全自适应的贝叶斯算法用于数据分析(Fabada)产生结果,没有任何参数调谐,与标准图像处理算法相当,其参数基于要恢复的真实信号进行了优化,在实际应用中不可能。诸如BM3D的最先进的非参数方法,以高信噪比提供稍微更好的性能,而我们的算法对于极其嘈杂的数据显着更准确(高于20-40 \%$相对错误,在天文领域特别兴趣的情况)。在此范围内,通过我们的重建获得的残差的标准偏差可能变得比原始测量值低的数量级。复制本报告中显示的所有结果所需的源代码,包括该方法的实现,在https://github.com/pablolyanala/fabada公开使用
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在过去十年中,图像已成为许多域中的重要信息来源,因此他们的高质量是获取更好信息的必要条件。出现的重要问题是图像去噪,这意味着从不准确和/或部分测量的样品中恢复信号。这种解释与压缩感测理论高度相关,这是一种革命性的技术,并且意味着如果信号稀疏,则可以从几个测量值获得原始信号,这些值远低于其他使用的理论所建议的值像Shannon的抽样理论。压缩传感(CS)理论的强因素以实现稀疏性解决方案以及从损坏的图像中移除的噪声是基础词典的选择。在本文中,比较了基于压缩感测和稀疏近似理论的高斯粘性白噪声的离散余弦变换(DCT)和力矩变换(TCHEBICHEF,KRAWTCHOUK)。实验结果表明,由矩变换构建的基本词典竞争性地表现为传统的DCT。后一种变换显示了30.82dB的PSNR,与Tchebichef变换相同的0.91 SSIM值。此外,从稀疏性的角度来看,Krawtchouk时刻提供大约20-30%的稀疏结果比DCT更多。
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We propose a natural scene statistic-based distortion-generic blind/no-reference (NR) image quality assessment (IQA) model that operates in the spatial domain. The new model, dubbed blind/referenceless image spatial quality evaluator (BRISQUE) does not compute distortion-specific features, such as ringing, blur, or blocking, but instead uses scene statistics of locally normalized luminance coefficients to quantify possible losses of "naturalness" in the image due to the presence of distortions, thereby leading to a holistic measure of quality. The underlying features used derive from the empirical distribution of locally normalized luminances and products of locally normalized luminances under a spatial natural scene statistic model. No transformation to another coordinate frame (DCT, wavelet, etc.) is required, distinguishing it from prior NR IQA approaches. Despite its simplicity, we are able to show that BRISQUE is statistically better than the full-reference peak signal-tonoise ratio and the structural similarity index, and is highly competitive with respect to all present-day distortion-generic NR IQA algorithms. BRISQUE has very low computational complexity, making it well suited for real time applications. BRISQUE features may be used for distortion-identification as well. To illustrate a new practical application of BRISQUE, we describe how a nonblind image denoising algorithm can be augmented with BRISQUE in order to perform blind image denoising. Results show that BRISQUE augmentation leads to performance improvements over state-of-the-art methods. A software release of BRISQUE is available online: http:// live.ece.utexas.edu/ research/ quality/ BRISQUE_release.zip for public use and evaluation.
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球形图像处理已被广泛应用于许多重要领域,例如自动驾驶汽车,全球气候建模和医学成像的全向视觉。扩展针对平面图像开发的算法的算法是非平凡的。在这项工作中,我们专注于具有基于深度学习的正常化程序的球形图像的具有挑战性的任务。我们采用了快速的方向球形帧转换,而不是对平面图像的现有模型的幼稚应用,并基于framelet变换的稀疏性假设而开发了一种新颖的优化框架。此外,通过采用渐进式编码器架构,经过精心设计的新的,表现出色的CNN Denoiser,可以作为隐式正规化程序进行设计。最后,我们使用插件方法来处理提出的优化模型,可以通过训练CNN Denoiser先验来有效地实现。进行了数值实验,并表明所提出的算法可以极大地恢复损坏的球形图像,并使用深度学习的DeNoiser和Paint-&play模型实现最佳性能。
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Deconvolution is a widely used strategy to mitigate the blurring and noisy degradation of hyperspectral images~(HSI) generated by the acquisition devices. This issue is usually addressed by solving an ill-posed inverse problem. While investigating proper image priors can enhance the deconvolution performance, it is not trivial to handcraft a powerful regularizer and to set the regularization parameters. To address these issues, in this paper we introduce a tuning-free Plug-and-Play (PnP) algorithm for HSI deconvolution. Specifically, we use the alternating direction method of multipliers (ADMM) to decompose the optimization problem into two iterative sub-problems. A flexible blind 3D denoising network (B3DDN) is designed to learn deep priors and to solve the denoising sub-problem with different noise levels. A measure of 3D residual whiteness is then investigated to adjust the penalty parameters when solving the quadratic sub-problems, as well as a stopping criterion. Experimental results on both simulated and real-world data with ground-truth demonstrate the superiority of the proposed method.
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图像恢复仍然是图像处理中有挑战性的任务。许多方法解决这个问题,通常通过最小化非平滑惩罚的共轨似然函数来解决。虽然解决方案很容易以理论保证来解释,但其估计依赖于可能需要时间的优化过程。考虑到图像分类和分割深度学习的研究努力,这类方法提供了一个严重的替代方案来执行图像恢复,但要挑战解决逆问题。在这项工作中,我们设计了一个名为Deeppdnet的深网络,从原始双近迭代构建,与之前的分析有关的标准惩罚可能性,允许我们利用两个世界。我们用固定图层为深度网络进行重构Condat-Vu原始 - 双混梯度(PDHG)算法的特定实例。学习的参数均为PDHG算法阶梯大小和惩罚中涉及的分析线性运算符(包括正则化参数)。允许这些参数从层变为另一个参数。提出了两种不同的学习策略:提出了“全学习”和“部分学习”,第一个是数值最有效的,而第二个是依赖于标准约束确保标准PDHG迭代中的收敛。此外,研究了全局和局部稀疏分析,以寻求更好的特征表示。我们将所提出的方法应用于MNIST和BSD68数据集上的图像恢复以及BSD100和SET14数据集的单个图像超分辨率。广泛的结果表明,建议的DeepPDNET在MNIST和更复杂的BSD68,BSD100和SET14数据集中展示了卓越的性能,用于图像恢复和单图像超分辨率任务。
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We address the image denoising problem, where zero-mean white and homogeneous Gaussian additive noise is to be removed from a given image. The approach taken is based on sparse and redundant representations over trained dictionaries. Using the K-SVD algorithm, we obtain a dictionary that describes the image content effectively. Two training options are considered: using the corrupted image itself, or training on a corpus of high-quality image database. Since the K-SVD is limited in handling small image patches, we extend its deployment to arbitrary image sizes by defining a global image prior that forces sparsity over patches in every location in the image. We show how such Bayesian treatment leads to a simple and effective denoising algorithm. This leads to a state-of-the-art denoising performance, equivalent and sometimes surpassing recently published leading alternative denoising methods.
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最近,从图像中提取的不同组件的低秩属性已经考虑在MAN Hypspectral图像去噪方法中。然而,这些方法通常将3D矩阵或1D向量展开,以利用现有信息,例如非识别空间自相似性(NSS)和全局光谱相关(GSC),其破坏了高光谱图像的内在结构相关性(HSI) )因此导致恢复质量差。此外,由于在HSI的原始高维空间中的矩阵和张量的矩阵和张量的参与,其中大多数受到重大计算负担问题。我们使用子空间表示和加权低级张量正则化(SWLRTR)进入模型中以消除高光谱图像中的混合噪声。具体地,为了在光谱频带中使用GSC,将噪声HSI投影到简化计算的低维子空间中。之后,引入加权的低级张量正则化术语以表征缩减图像子空间中的前导。此外,我们设计了一种基于交替最小化的算法来解决非耦合问题。模拟和实时数据集的实验表明,SWLRTR方法比定量和视觉上的其他高光谱去噪方法更好。
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基于深度学习的高光谱图像(HSI)恢复方法因其出色的性能而广受欢迎,但每当任务更改的细节时,通常都需要昂贵的网络再培训。在本文中,我们建议使用有效的插入方法以统一的方法恢复HSI,该方法可以共同保留基于优化方法的灵活性,并利用深神经网络的强大表示能力。具体而言,我们首先开发了一个新的深HSI DeNoiser,利用了门控复发单元,短期和长期的跳过连接以及增强的噪声水平图,以更好地利用HSIS内丰富的空间光谱信息。因此,这导致在高斯和复杂的噪声设置下,在HSI DeNosing上的最新性能。然后,在处理各种HSI恢复任务之前,将提议的DeNoiser插入即插即用的框架中。通过对HSI超分辨率,压缩感测和内部进行的广泛实验,我们证明了我们的方法经常实现卓越的性能,这与每个任务上的最先进的竞争性或甚至更好任何特定任务的培训。
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低级别在高光谱图像(HSI)降级任务中很重要。根据张量的奇异值分解定义的张量核标准(TNN)是描述HSI低级别的最新方法。但是,TNN忽略了HSI在解决deno的任务时的某些身体含义,从而导致了次优的降级性能。在本文中,我们提出了用于HSI降解任务的多模式和频率加权张量核定常(MFWTNN)和非凸MFWTNN。首先,我们研究了频率切片的物理含义,并重新考虑其权重以提高TNN的低级别表示能力。其次,我们考虑两个空间维度和HSI的光谱维度之间的相关性,并将上述改进与TNN相结合以提出MFWTNN。第三,我们使用非凸功能来近似频率张量的秩函数,并提出非MFWTNN以更好地放松MFWTNN。此外,我们自适应地选择更大的权重,用于切片,主要包含噪声信息和较小的重量,用于包含配置文件信息的切片。最后,我们开发了基于乘数(ADMM)算法的有效交替方向方法来求解所提出的模型,并在模拟和真实的HSI数据集中证实了我们的模型的有效性。
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图像生物标准化倡议(IBSI)旨在通过标准化从图像中提取图像生物标志物(特征)的计算过程来提高射致研究的再现性。我们之前建立了169个常用特征的参考值,创建了标准的射频图像处理方案,并开发了用于垄断研究的报告指南。但是,若干方面没有标准化。在这里,我们提出了在射频中使用卷积图像过滤器的参考手册的初步版本。滤波器,例如高斯滤波器的小波或拉普拉斯,在强调特定图像特征(如边缘和Blob)中发挥重要组成部分。已发现从过滤滤波器响应图派生的功能可重复差。此参考手册构成了持续工作的基础,用于标准化卷积滤波器中的覆盖物中的持续工作,并在这项工作进行时更新。
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基于深度学习(DL)的高光谱图像(HSIS)去噪方法直接学习观察到的嘈杂图像和底层清洁图像之间的非线性映射。他们通常不考虑HSIS的物理特征,因此使他们缺乏了解他们的去噪机制的关键。为了解决这个问题,我们为HSI去噪提出了一种新颖的模型指导可解释网络。具体而言,完全考虑HSI的空间冗余,光谱低秩和光谱空间特性,我们首先建立基于子空间的多维稀疏模型。该模型首先将观察到的HSIS投入到低维正交子空间,然后表示具有多维字典的投影图像。之后,该模型展开到名为SMDS-Net的端到端网络中,其基本模块与模型的去噪程序无缝连接。这使得SMDS-Net传达清晰的物理意义,即学习HSIS的低级别和稀疏性。最后,通过端到端培训获得包括词典和阈值处理的所有关键变量。广泛的实验和综合分析证实了我们对最先进的HSI去噪方法的方法的去噪能力和可解释性。
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It is known that the decomposition in low-rank and sparse matrices (\textbf{L+S} for short) can be achieved by several Robust PCA techniques. Besides the low rankness, the local smoothness (\textbf{LSS}) is a vitally essential prior for many real-world matrix data such as hyperspectral images and surveillance videos, which makes such matrices have low-rankness and local smoothness properties at the same time. This poses an interesting question: Can we make a matrix decomposition in terms of \textbf{L\&LSS +S } form exactly? To address this issue, we propose in this paper a new RPCA model based on three-dimensional correlated total variation regularization (3DCTV-RPCA for short) by fully exploiting and encoding the prior expression underlying such joint low-rank and local smoothness matrices. Specifically, using a modification of Golfing scheme, we prove that under some mild assumptions, the proposed 3DCTV-RPCA model can decompose both components exactly, which should be the first theoretical guarantee among all such related methods combining low rankness and local smoothness. In addition, by utilizing Fast Fourier Transform (FFT), we propose an efficient ADMM algorithm with a solid convergence guarantee for solving the resulting optimization problem. Finally, a series of experiments on both simulations and real applications are carried out to demonstrate the general validity of the proposed 3DCTV-RPCA model.
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盐和辣椒噪声去除是图像处理中的常见问题。传统的去噪方法有两个限制。首先,通常未准确描述噪声特性。例如,噪声位置信息通常被忽略,并且盐和辣椒噪声的稀疏性通常由L1标准描述,这不能清楚地示出稀疏变量。其次,传统方法将污染图像分离成恢复的图像和噪声部分,从而导致恢复具有不满足平滑部件和细节部件的图像。在本研究中,我们引入了噪声检测策略来确定噪声的位置,并且采用由LP准规范描绘的非凸稀稀曲面正规化来描述噪声的稀疏性,从而解决了第一个限制。采用静止框架变换的形态分析框架将处理的图像分解为卡通,纹理和噪声部件以解决第二个限制。然后,采用乘法器(ADMM)的交替方向方法来解决所提出的模型。最后,进行实验以验证所提出的方法,并将其与一些最新的最先进的去噪方法进行比较。实验结果表明,该方法可以在保留加工图像的细节时去除盐和辣椒噪声。
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现代社会有兴趣由于复杂的相机的激增而捕获高分辨率和优质图像。但是,如果在计算机视觉任务中使用了此类图像,则图像中的噪声污染不仅较低,而且相反会影响随后的过程,例如遥感,对象跟踪等。高分辨率图像的时间处理受图像捕获仪器的硬件限制的限制。 Geodesic Gramian denoising(GGD)是一种基于多种噪声滤波方法,我们在过去的研究中介绍了该方法,它利用了Geodesics的Gramian Gramian矩阵的一些突出的奇异向量进行噪声滤波过程。 GDD遇到$ \ MATHCAL {O}(n^6)$时,GDD的适用性受到限制^2 $数据矩阵由单数值分解(SVD)实现。在这项研究中,我们通过用四种不同的单数矢量近似技术代替其SVD步骤来提高GGD框架的效率。在这里,我们比较集成到GGD中的四个技术之间的计算时间和噪声过滤性能。
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图像去噪是许多领域下游任务的先决条件。低剂量和光子计数计算断层扫描(CT)去噪可以在最小化辐射剂量下优化诊断性能。监督深层去噪方法是流行的,但需要成对的清洁或嘈杂的样本通常在实践中不可用。受独立噪声假设的限制,电流无监督的去噪方法不能处理与CT图像中的相关噪声。在这里,我们提出了一种基于类似的类似性的无人监督的无监督的深度去噪方法,称为Coxing2Sim,以非局部和非线性方式起作用,不仅抑制独立而且还具有相关的噪音。从理论上讲,噪声2SIM在温和条件下渐近相当于监督学习方法。通过实验,Nosie2SIM从嘈杂的低剂量CT和光子计数CT图像中的内在特征,从视觉上,定量和统计上有效地或甚至优于实际数据集的监督学习方法。 Coke2Sim是一般无监督的去噪方法,在不同的应用中具有很大的潜力。
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