事实证明,生成对抗网络(GAN)在建模高维数据的分布中有效。但是,他们的训练不稳定性是融合的众所周知的障碍,这导致了他们对新数据的应用实践挑战。此外,即使达到收敛,甘恩也可能会受到模式崩溃的影响,模式崩溃是生成器学会仅建模目标分布的一小部分的现象,而无视绝大多数数据歧管或分布。本文通过引入SETGAN来解决这些挑战,Setgan是一种对抗性架构,该架构处理生成和真实样本的集合,并以灵活的,置换的不变方式区分这些集合的起源(即培训与生成数据)。我们还提出了一个新的指标,以定量评估gan,除了数据本身外,不需要以前的应用程序知识。使用新的度量标准,结合最新的评估方法,我们表明,与来自类似策略的GAN变体相比,所提出的体系结构以同样的方式生成更准确的输入数据模型对高参数设置的敏感性较差。
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我们提出了一种具有多个鉴别器的生成的对抗性网络,其中每个鉴别者都专门用于区分真实数据集的子集。这种方法有助于学习与底层数据分布重合的发电机,从而减轻慢性模式崩溃问题。从多项选择学习的灵感来看,我们引导每个判别者在整个数据的子集中具有专业知识,并允许发电机在没有监督训练示例和鉴别者的数量的情况下自动找到潜伏和真实数据空间之间的合理对应关系。尽管使用多种鉴别器,但骨干网络在鉴别器中共享,并且培训成本的增加最小化。我们使用多个评估指标展示了我们算法在标准数据集中的有效性。
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现代生成模型大致分为两个主要类别:(1)可以产生高质量随机样品但无法估算新数据点的确切密度的模型,以及(2)提供精确密度估计的模型,以样本为代价潜在空间的质量和紧凑性。在这项工作中,我们提出了LED,这是一种与gan密切相关的新生成模型,不仅允许有效采样,而且允许有效的密度估计。通过最大程度地提高对数可能的歧视器输出,我们得出了一个替代对抗优化目标,鼓励生成的数据多样性。这种表述提供了对几种流行生成模型之间关系的见解。此外,我们构建了一个基于流的生成器,该发电机可以计算生成样品的精确概率,同时允许低维度变量作为输入。我们在各种数据集上的实验结果表明,我们的密度估计器会产生准确的估计值,同时保留了生成的样品质量良好。
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Generative adversarial networks (GANs) provide a way to learn deep representations without extensively annotated training data. They achieve this through deriving backpropagation signals through a competitive process involving a pair of networks. The representations that can be learned by GANs may be used in a variety of applications, including image synthesis, semantic image editing, style transfer, image super-resolution and classification. The aim of this review paper is to provide an overview of GANs for the signal processing community, drawing on familiar analogies and concepts where possible. In addition to identifying different methods for training and constructing GANs, we also point to remaining challenges in their theory and application.
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虽然生成的对抗网络(GaN)是他们对其更高的样本质量的流行,而与其他生成模型相反,但是它们遭受同样困难的产生样本的难度。必须牢记各个方面,如产生的样本的质量,课程的多样性(在课堂内和类别中),使用解除戒开的潜在空间,所述评估度量的协议与人类感知等。本文,我们提出了一个新的评分,即GM分数,这取得了各种因素,如样品质量,解除戒备的代表,阶级,级别的阶级和级别多样性等各种因素,以及诸如精确,召回和F1分数等其他指标用于可怜的性深度信仰网络(DBN)和限制Boltzmann机(RBM)的潜在空间。评估是针对不同的GANS(GAN,DCGAN,BIGAN,CGAN,CONFORDGON,LSGAN,SGAN,WAN,以及WGAN改进)的不同GANS(GAN,DCGAN,BIGAN,SCAN,WANT)在基准MNIST数据集上培训。
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生成对抗网络(GAN)的最新发展驱动了许多计算机视觉应用。尽管综合质量很高,但训练甘斯经常会面临几个问题,包括非缔合,模式崩溃和梯度消失。有几个解决方法,例如,正规化Lipschitz的连续性和采用Wasserstein距离。尽管这些方法可以部分解决问题,但我们认为这些问题是由于用深神经网络对歧视者建模而引起的。在本文中,我们基于新衍生的深神网络理论,称为神经切线内核(NTK),并提出了一种称为生成对抗性NTK(GA-NTK)的新生成算法。 GA-NTK将鉴别器建模为高斯过程(GP)。借助NTK理论,可以用封闭式公式来描述GA-NTK的训练动力学。为了将数据与封闭形式公式合成,可以将目标简化为单层对抗优化问题。我们在现实世界数据集上进行了广泛的实验,结果表明,GA-NTK可以生成与GAN相当的图像,但在各种条件下训练要容易得多。我们还研究了GA-NTK的当前局限性,并提出了一些解决方法,以使GA-NTK更加实用。
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We investigate the training and performance of generative adversarial networks using the Maximum Mean Discrepancy (MMD) as critic, termed MMD GANs. As our main theoretical contribution, we clarify the situation with bias in GAN loss functions raised by recent work: we show that gradient estimators used in the optimization process for both MMD GANs and Wasserstein GANs are unbiased, but learning a discriminator based on samples leads to biased gradients for the generator parameters. We also discuss the issue of kernel choice for the MMD critic, and characterize the kernel corresponding to the energy distance used for the Cramér GAN critic. Being an integral probability metric, the MMD benefits from training strategies recently developed for Wasserstein GANs. In experiments, the MMD GAN is able to employ a smaller critic network than the Wasserstein GAN, resulting in a simpler and faster-training algorithm with matching performance. We also propose an improved measure of GAN convergence, the Kernel Inception Distance, and show how to use it to dynamically adapt learning rates during GAN training.
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最近,基于转换的自我监督学习已经应用于生成的对抗性网络(GANS),通过引入静止学习环境来缓解争夺者中的灾难性遗忘。然而,现有的自我监督GAN中的单独自我监督任务导致目标不一致,因为它们的自我监督分类器对发电机分配不可知。为了解决这个问题,我们提出了一种新颖的自我监督GaN,通过自我监督通过数据转换增强GaN标签(真实或假),将GaN任务统一了GAN任务。具体地,原始鉴别器和自我监督分类器统一到标签增强的鉴别器中,预测增强标签要知道每个转换下的发电机分配和数据分布,然后提供它们之间的差异以优化发电机。从理论上讲,我们证明了最佳发生器可以收敛以复制实际数据分布。凭经验,我们表明,该方法显着优异地优于先前的自我监督和数据增强GAN在基准数据集中的生成建模和代表学习。
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Mode collapse is still a major unsolved problem in generative adversarial networks. In this work, we analyze the causes of mode collapse from a new perspective. Due to the nonuniform sampling in the training process, some sub-distributions can be missed while sampling data. Therefore, the GAN objective can reach the minimum when the generated distribution is not the same as the real one. To alleviate the problem, we propose a global distribution fitting (GDF) method by a penalty term to constrain generated data distribution. On the basis of not changing the global minimum of the GAN objective, GDF will make it harder to reach the minimum value when the generated distribution is not the same as the real one. Furthermore, we also propose a local distribution fitting (LDF) method to cope with the situation that the real distribution is unknown. Experiments on several benchmarks demonstrate the effectiveness and competitive performance of GDF and LDF.
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与CNN的分类,分割或对象检测相比,生成网络的目标和方法根本不同。最初,它们不是作为图像分析工具,而是生成自然看起来的图像。已经提出了对抗性训练范式来稳定生成方法,并已被证明是非常成功的 - 尽管绝不是第一次尝试。本章对生成对抗网络(GAN)的动机进行了基本介绍,并通​​过抽象基本任务和工作机制并得出了早期实用方法的困难来追溯其成功的道路。将显示进行更稳定的训练方法,也将显示出不良收敛及其原因的典型迹象。尽管本章侧重于用于图像生成和图像分析的gan,但对抗性训练范式本身并非特定于图像,并且在图像分析中也概括了任务。在将GAN与最近进入场景的进一步生成建模方法进行对比之前,将闻名图像语义分割和异常检测的架构示例。这将允许对限制的上下文化观点,但也可以对gans有好处。
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本文提出了有条件生成对抗性网络(CGANS)的两个重要贡献,以改善利用此架构的各种应用。第一个主要贡献是对CGANS的分析表明它们没有明确条件。特别地,将显示鉴别者和随后的Cgan不会自动学习输入之间的条件。第二种贡献是一种新方法,称为逆时针,该方法通过新颖的逆损失明确地模拟了对抗架构的两部分的条件,涉及培训鉴别者学习无条件(不利)示例。这导致了用于GANS(逆学习)的新型数据增强方法,其允许使用不利示例将发电机的搜索空间限制为条件输出。通过提出概率分布分析,进行广泛的实验以评估判别符的条件。与不同应用的CGAN架构的比较显示了众所周知的数据集的性能的显着改进,包括使用不同度量的不同度量的语义图像合成,图像分割,单眼深度预测和“单个标签” - 图像(FID) ),平均联盟(Miou)交叉口,根均线误差日志(RMSE日志)和统计上不同的箱数(NDB)。
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We introduce a new algorithm named WGAN, an alternative to traditional GAN training. In this new model, we show that we can improve the stability of learning, get rid of problems like mode collapse, and provide meaningful learning curves useful for debugging and hyperparameter searches. Furthermore, we show that the corresponding optimization problem is sound, and provide extensive theoretical work highlighting the deep connections to different distances between distributions.
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我们研究了GaN调理问题,其目标是使用标记数据将普雷雷尼的无条件GaN转换为条件GaN。我们首先识别并分析这一问题的三种方法 - 从头开始​​,微调和输入重新编程的条件GaN培训。我们的分析表明,当标记数据的数量很小时,输入重新编程执行最佳。通过稀缺标记数据的现实世界情景,我们专注于输入重编程方法,并仔细分析现有算法。在识别出先前输入重新编程方法的一些关键问题之后,我们提出了一种名为INREP +的新算法。我们的算法INREP +解决了现有问题,具有可逆性神经网络的新颖用途和正面未标记(PU)学习。通过广泛的实验,我们表明Inrep +优于所有现有方法,特别是当标签信息稀缺,嘈杂和/或不平衡时。例如,对于用1%标记数据调节CiFar10 GaN的任务,Inrep +实现了82.13的平均峰值,而第二个最佳方法达到114.51。
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这是关于生成对抗性网络(GaN),对抗性自身额外的教程和调查纸张及其变体。我们开始解释对抗性学习和香草甘。然后,我们解释了条件GaN和DCGAN。介绍了模式崩溃问题,介绍了各种方法,包括小纤维GaN,展开GaN,Bourgan,混合GaN,D2Gan和Wasserstein GaN,用于解决这个问题。然后,GaN中的最大似然估计与F-GaN,对抗性变分贝叶斯和贝叶斯甘甘相同。然后,我们涵盖了GaN,Infogan,Gran,Lsgan,Enfogan,Gran,Lsgan,Catgan,MMD Gan,Lapgan,Progressive Gan,Triple Gan,Lag,Gman,Adagan,Cogan,逆甘,Bigan,Ali,Sagan,Sagan,Sagan,Sagan,甘肃,甘肃,甘河的插值和评估。然后,我们介绍了GaN的一些应用,例如图像到图像转换(包括Pacchgan,Cyclegan,Deepfacedrawing,模拟GaN,Interactive GaN),文本到图像转换(包括Stackgan)和混合图像特征(包括罚球和mixnmatch)。最后,我们解释了基于对冲学习的AutoEncoders,包括对手AutoEncoder,Pixelgan和隐式AutoEncoder。
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为了稳定地训练生成对抗网络(GAN),将实例噪声注入歧视器的输入中被认为是理论上的声音解决方案,但是,在实践中尚未实现其承诺。本文介绍了采用高斯混合物分布的扩散 - 在正向扩散链的所有扩散步骤中定义,以注入实例噪声。从观察到或生成的数据扩散的混合物中的随机样品被作为歧视器的输入。通过将其梯度通过前向扩散链进行反向传播来更新,该链的长度可自适应地调节以控制每个训练步骤允许的最大噪声与数据比率。理论分析验证了所提出的扩散gan的声音,该扩散器提供了模型和域 - 不可分割的可区分增强。在各种数据集上进行的一系列实验表明,扩散 - GAN可以提供稳定且具有数据效率的GAN训练,从而使对强GAN基准的性能保持一致,以综合构成照片现实的图像。
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We describe a new training methodology for generative adversarial networks. The key idea is to grow both the generator and discriminator progressively: starting from a low resolution, we add new layers that model increasingly fine details as training progresses. This both speeds the training up and greatly stabilizes it, allowing us to produce images of unprecedented quality, e.g., CELEBA images at 1024 2 . We also propose a simple way to increase the variation in generated images, and achieve a record inception score of 8.80 in unsupervised CIFAR10. Additionally, we describe several implementation details that are important for discouraging unhealthy competition between the generator and discriminator. Finally, we suggest a new metric for evaluating GAN results, both in terms of image quality and variation. As an additional contribution, we construct a higher-quality version of the CELEBA dataset.
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Generative adversarial networks (GANs) are a class of machine-learning models that use adversarial training to generate new samples with the same (potentially very complex) statistics as the training samples. One major form of training failure, known as mode collapse, involves the generator failing to reproduce the full diversity of modes in the target probability distribution. Here, we present an effective model of GAN training, which captures the learning dynamics by replacing the generator neural network with a collection of particles in the output space; particles are coupled by a universal kernel valid for certain wide neural networks and high-dimensional inputs. The generality of our simplified model allows us to study the conditions under which mode collapse occurs. Indeed, experiments which vary the effective kernel of the generator reveal a mode collapse transition, the shape of which can be related to the type of discriminator through the frequency principle. Further, we find that gradient regularizers of intermediate strengths can optimally yield convergence through critical damping of the generator dynamics. Our effective GAN model thus provides an interpretable physical framework for understanding and improving adversarial training.
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In biomedical image analysis, the applicability of deep learning methods is directly impacted by the quantity of image data available. This is due to deep learning models requiring large image datasets to provide high-level performance. Generative Adversarial Networks (GANs) have been widely utilized to address data limitations through the generation of synthetic biomedical images. GANs consist of two models. The generator, a model that learns how to produce synthetic images based on the feedback it receives. The discriminator, a model that classifies an image as synthetic or real and provides feedback to the generator. Throughout the training process, a GAN can experience several technical challenges that impede the generation of suitable synthetic imagery. First, the mode collapse problem whereby the generator either produces an identical image or produces a uniform image from distinct input features. Second, the non-convergence problem whereby the gradient descent optimizer fails to reach a Nash equilibrium. Thirdly, the vanishing gradient problem whereby unstable training behavior occurs due to the discriminator achieving optimal classification performance resulting in no meaningful feedback being provided to the generator. These problems result in the production of synthetic imagery that is blurry, unrealistic, and less diverse. To date, there has been no survey article outlining the impact of these technical challenges in the context of the biomedical imagery domain. This work presents a review and taxonomy based on solutions to the training problems of GANs in the biomedical imaging domain. This survey highlights important challenges and outlines future research directions about the training of GANs in the domain of biomedical imagery.
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生成对抗网络(GAN)是使用一组真实示例生成假数据的框架。但是,甘在训练阶段不稳定。为了稳定gan,噪声注入已被用来扩大真实和虚假分布的重叠,而差异为增加。扩散(或平滑)可能会降低数据的固有潜在维度,但它抑制了甘斯在训练程序中学习高频信息的能力。基于这些观察结果,我们为GAN训练(称为嘈杂的尺度空间(NSS))提出了一个数据表示,该数据表示用平衡的噪声将平滑性应用于数据,以通过随机数据替换高频信息,从而导致高频信息。对gan的粗到精细训练。我们基于基于基准数据集的DCGAN和stylegan2尝试NSS,在大多数情况下,基于NSS的GANS的gans优于最先进的方法。
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生成对抗网络(GAN)是基于生成器和歧视器之间的两种玩家游戏的一类分配学习方法,通常可以根据未知与生成的生成的差异表示的变异表示形式来表达为Minmax问题。分布。我们通过开发针对差异的新变分表示,将结构传播的gans作为学习分布的数据效率框架。我们的理论表明,我们可以利用与与基础结构相关的Sigma-algebra的条件期望,将歧视空间缩小为对不变歧视空间的投影。此外,我们证明了鉴别空间的缩小必须伴随着结构化发电机的仔细设计,因为有缺陷的设计很容易导致学习分布的灾难性的“模式崩溃”。我们通过构建具有对称性的gan来进行固有的群体对称性分布来使我们的框架背景化,并证明两个参与者,即epoiriant发电机和不变歧视者,都在学习过程中扮演重要但独特的角色。跨广泛的数据集的经验实验和消融研究,包括现实世界的医学成像,验证我们的理论,并显示我们所提出的方法可显着提高样品保真度和多样性 - 几乎是在FR \'Echet Intection中衡量的数量级距离 - 尤其是在小型数据制度中。
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