深尾学习旨在培训有用的深层网络，以实用现实世界中的不平衡分布，其中大多数尾巴类别的标签都与一些样本相关联。有大量的工作来训练判别模型，以进行长尾分布的视觉识别。相比之下，我们旨在训练有条件的生成对抗网络，这是一类长尾分布的图像生成模型。我们发现，类似于识别图像产生的最新方法类似，也遭受了尾部类别的性能降解。性能降解主要是由于尾部类别的类别模式塌陷，我们观察到与调节参数矩阵的光谱爆炸相关。我们提出了一种新型的组光谱正规剂（GSR），以防止光谱爆炸减轻模式崩溃，从而导致尾巴类别的形象产生多样化和合理的图像产生。我们发现GSR有效地与现有的增强和正则化技术结合在一起，从而导致长尾数据上的最新图像生成性能。广泛的实验证明了我们的常规器在不同程度不平衡的长尾数据集上的功效。

条件生成的对抗性网络（CGAN）通过将类信息纳入GaN来生成现实图像。虽然最受欢迎的CGANS是一种辅助分类器GAN，但众所周知，随着数据集中的类别的数量增加，培训acgan正在挑战。偶数还倾向于产生缺乏多样性的容易甲型样本。在本文中，我们介绍了两种治疗方法。首先，我们识别分类器中的梯度爆炸可能会导致早期训练中的不良崩溃，并将输入向量投影到单元间隔子上可以解决问题。其次，我们提出了数据到数据跨熵丢失（D2D-CE）来利用类标记的数据集中的关系信息。在这个基础上，我们提出了重新启动的辅助分类器生成对抗网络（Reacgan）。实验结果表明，Reacgan在CIFAR10，微小想象成，CUB200和Imagenet数据集上实现了最先进的生成结果。我们还验证了来自可分辨率的增强的ReacanggaN的利益，以及D2D-CE与Stylegan2架构协调。模型权重和提供代表性CGANS实现的软件包和我们纸上的所有实验都可以在https://github.com/postech-cvlab/pytorch-studiogan获得。

生成对抗网络（GAN）是现实图像合成的最新生成模型之一。虽然培训和评估GAN变得越来越重要，但当前的GAN研究生态系统并未提供可靠的基准，以始终如一地进行评估。此外，由于GAN实施很少，因此研究人员将大量时间用于重现基线。我们研究了GAN方法的分类法，并提出了一个名为Studiogan的新开源库。 Studiogan支持7种GAN体系结构，9种调理方法，4种对抗损失，13个正则化模块，3个可区分的增强，7个评估指标和5个评估骨干。通过我们的培训和评估协议，我们使用各种数据集（CIFAR10，ImageNet，AFHQV2，FFHQ和Baby/Papa/Granpa-Imagenet）和3个不同的评估骨干（InceptionV3，Swav，Swav和Swin Transformer）提出了大规模的基准。与GAN社区中使用的其他基准不同，我们在统一的培训管道中培训了包括Biggan，stylegan2和stylegan3在内的代表GAN，并使用7个评估指标量化了生成性能。基准测试评估其他尖端生成模型（例如，stylegan-xl，adm，maskgit和rq-transformer）。 Studiogan提供了预先训练的权重的GAN实现，培训和评估脚本。 Studiogan可从https://github.com/postech-cvlab/pytorch-studiogan获得。

The performance of generative adversarial networks (GANs) heavily deteriorates given a limited amount of training data. This is mainly because the discriminator is memorizing the exact training set. To combat it, we propose Differentiable Augmentation (DiffAugment), a simple method that improves the data efficiency of GANs by imposing various types of differentiable augmentations on both real and fake samples. Previous attempts to directly augment the training data manipulate the distribution of real images, yielding little benefit; DiffAugment enables us to adopt the differentiable augmentation for the generated samples, effectively stabilizes training, and leads to better convergence. Experiments demonstrate consistent gains of our method over a variety of GAN architectures and loss functions for both unconditional and class-conditional generation. With DiffAugment, we achieve a state-of-the-art FID of 6.80 with an IS of 100.8 on ImageNet 128×128 and 2-4× reductions of FID given 1,000 images on FFHQ and LSUN. Furthermore, with only 20% training data, we can match the top performance on CIFAR-10 and CIFAR-100. Finally, our method can generate high-fidelity images using only 100 images without pre-training, while being on par with existing transfer learning algorithms. Code is available at https://github.com/mit-han-lab/data-efficient-gans.

生成的对抗网络（GANS）可以在狭窄的域中的照片逼真图像附近生成，例如人面。然而，模拟数据集的复杂分布，如想象成和Coco-ince，在无条件设置中仍然具有挑战性。在本文中，我们从内核密度估计技术中获取灵感并引入非参数方法来建模复杂数据集的分布。我们将数据歧管分为数据点及其最近邻居描述的重叠邻域的混合，并介绍一个名为实例条件GaN（IC-GaN）的模型，该模型将从每个数据点周围的分布中生动分布。 Imagenet和Coco-Stump的实验结果表明，IC-GaN显着改善了无条件模型和无监督数据分区基线。此外，我们表明IC-GaN可以通过简单地改变调节实例来毫不费力地转移到训练期间未见的数据集，并且仍然产生现实图像。最后，我们将IC-GAN扩展到课堂条件情况下，并在想象中显示语义可控的发电和竞争定量结果;同时在想象中改善了大战。在https://github.com/facebookResearch/IC_GAN中提供了重现报告结果的代码和训练有素的模型。

Despite recent progress in generative image modeling, successfully generating high-resolution, diverse samples from complex datasets such as ImageNet remains an elusive goal. To this end, we train Generative Adversarial Networks at the largest scale yet attempted, and study the instabilities specific to such scale. We find that applying orthogonal regularization to the generator renders it amenable to a simple "truncation trick," allowing fine control over the trade-off between sample fidelity and variety by reducing the variance of the Generator's input. Our modifications lead to models which set the new state of the art in class-conditional image synthesis. When trained on ImageNet at 128×128 resolution, our models (BigGANs) achieve an Inception Score (IS) of 166.5 and Fréchet Inception Distance (FID) of 7.4, improving over the previous best IS of 52.52 and FID of 18.65.

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。

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。

生成的对抗网络（GANS）产生高质量的图像，但致力于训练。它们需要仔细正常化，大量计算和昂贵的超参数扫描。我们通过将生成和真实样本投影到固定的预级特征空间中，在这些问题上进行了重要的头路。发现鉴别者无法充分利用来自预押模型的更深层次的特征，我们提出了更有效的策略，可以在渠道和分辨率中混合特征。我们预计的GaN提高了图像质量，样品效率和收敛速度。它与最多一个百万像素的分辨率进一步兼容，并在二十二个基准数据集上推进最先进的FR \'Echet Inception距离（FID）。重要的是，预计的GAN符合先前最低的FID速度快40倍，鉴于相同的计算资源，将壁钟时间从5天切割到不到3小时。

One of the challenges in the study of generative adversarial networks is the instability of its training. In this paper, we propose a novel weight normalization technique called spectral normalization to stabilize the training of the discriminator. Our new normalization technique is computationally light and easy to incorporate into existing implementations. We tested the efficacy of spectral normalization on CIFAR10, STL-10, and ILSVRC2012 dataset, and we experimentally confirmed that spectrally normalized GANs (SN-GANs) is capable of generating images of better or equal quality relative to the previous training stabilization techniques. The code with Chainer (Tokui et al., 2015), generated images and pretrained models are available at https://github.com/pfnet-research/sngan_ projection.

近年来有条件的GAN已经成熟，并且能够产生高质量的现实形象。但是，计算资源和培训高质量的GAN所需的培训数据是巨大的，因此对这些模型的转移学习的研究是一个紧急话题。在本文中，我们探讨了从高质量预训练的无条件GAN到有条件的GAN的转移。为此，我们提出了基于HyperNetwork的自适应权重调制。此外，我们介绍了一个自我初始化过程，不需要任何真实数据才能初始化HyperNetwork参数。为了进一步提高知识转移的样本效率，我们建议使用自我监督（对比）损失来改善GaN判别者。在广泛的实验中，我们验证了多个标准基准上的Hypernetworks，自我初始化和对比损失的效率。

Training generative adversarial networks (GAN) using too little data typically leads to discriminator overfitting, causing training to diverge. We propose an adaptive discriminator augmentation mechanism that significantly stabilizes training in limited data regimes. The approach does not require changes to loss functions or network architectures, and is applicable both when training from scratch and when fine-tuning an existing GAN on another dataset. We demonstrate, on several datasets, that good results are now possible using only a few thousand training images, often matching StyleGAN2 results with an order of magnitude fewer images. We expect this to open up new application domains for GANs. We also find that the widely used CIFAR-10 is, in fact, a limited data benchmark, and improve the record FID from 5.59 to 2.42.

GAN的进展使高分辨率的感性质量形象产生了产生。 stylegans允许通过数学操作对W/W+空间中的潜在样式向量进行数学操作进行引人入胜的属性修改，从而有效调节生成器的丰富层次结构表示。最近，此类操作已被推广到原始StyleGan纸中的属性交换之外，以包括插值。尽管StyleGans有许多重大改进，但仍被认为会产生不自然的图像。生成的图像的质量基于两个假设。 （a）生成器学到的层次表示的丰富性，以及（b）样式空间的线性和平滑度。在这项工作中，我们提出了一个层次的语义正常化程序（HSR），该层次正常化程序将生成器学到的层次表示与大量数据学到的相应的强大功能保持一致。 HSR不仅可以改善发电机的表示，还可以改善潜在风格空间的线性和平滑度，从而导致产生更自然的样式编辑的图像。为了证明线性改善，我们提出了一种新型的度量 - 属性线性评分（ALS）。通过改善感知路径长度（PPL）度量的改善，在不同的标准数据集中平均16.19％的不自然图像的生成显着降低，同时改善了属性编辑任务中属性变化的线性变化。

In this paper, we propose the Self-Attention Generative Adversarial Network (SAGAN) which allows attention-driven, long-range dependency modeling for image generation tasks. Traditional convolutional GANs generate high-resolution details as a function of only spatially local points in lower-resolution feature maps. In SAGAN, details can be generated using cues from all feature locations. Moreover, the discriminator can check that highly detailed features in distant portions of the image are consistent with each other. Furthermore, recent work has shown that generator conditioning affects GAN performance. Leveraging this insight, we apply spectral normalization to the GAN generator and find that this improves training dynamics. The proposed SAGAN performs better than prior work 1 , boosting the best published Inception score from 36.8 to 52.52 and reducing Fréchet Inception distance from 27.62 to 18.65 on the challenging ImageNet dataset. Visualization of the attention layers shows that the generator leverages neighborhoods that correspond to object shapes rather than local regions of fixed shape.

现代生成的对抗网络（GANS）主要使用判别者（或批评者）中的分段线性激活功能，包括Relu和Leaceryru。这些模型学习分段线性映射，其中每个部分处理输入空间的子集，每个子​​集的梯度​​是分段常数。在这样一类鉴别者（或批评者）函数下，我们呈现梯度标准化（Gran），一种新的输入相关标准化方法，可确保输入空间中的分段k-lipschitz约束。与光谱归一化相比，Gran不约束各个网络层的处理，并且与梯度惩罚不同，严格执行几乎无处不在的分段Lipschitz约束。凭经验，我们展示了多个数据集的改进了图像生成性能（包括Cifar-10/100，STL-10，LSUN卧室和Celeba），GaN丢失功能和指标。此外，我们分析了在几个标准GAN中改变了经常无核的Lipschitz常数K，而不仅仅是实现显着的性能增益，还可以在普通的ADAM优化器中找到K和培训动态之间的连接，特别是在低梯度损失平台之间。

有条件的生成对抗网络（CGANs）将标准无条件GaN框架扩展到学习样本的联合数据标签分布，并已建立为能够产生高保真图像的强大生成模型。这种模型的训练挑战在于将课程信息恰当地注入到其发电机和鉴别器中。对于鉴别器，可以通过（1）直接将标签作为输入或（2）涉及辅助分类损失的标签来实现类调节。在本文中，我们表明前者直接对齐类条件的假和实际数据分布$ p（\ text {image} | \ text {class}）$（{\ EM数据匹配}），而后者对齐数据调节类分布$ p（\ text {class} | \ text {image}）$（{\ EM标签匹配}）。虽然类别可分离性并不直接转化为样本质量，并且如果分类本身是本质上困难的话，如果不同类别的特征映射到同一点，则不能为发电机提供有用的指导，因此可以为同一点映射并因此变得不可分割。通过这种直觉激励，我们提出了一种双重投影GaN（P2Gan）模型，它学会在{\ EM数据匹配}和{\ EM标签匹配}之间平衡。然后，我们提出了一种改进的Cgan模型，通过辅助分类，通过最大限度地减少$ F $ -divergence，通过辅助分类直接对准假和实际条件$ p（\ text {class} | \ text {image}）$。高斯（MOG）数据集的合成混合物和各种现实世界数据集的实验，包括CIFAR100，ImageNet和Vggface2，证明了我们所提出的模型的功效。

The style-based GAN architecture (StyleGAN) yields state-of-the-art results in data-driven unconditional generative image modeling. We expose and analyze several of its characteristic artifacts, and propose changes in both model architecture and training methods to address them. In particular, we redesign the generator normalization, revisit progressive growing, and regularize the generator to encourage good conditioning in the mapping from latent codes to images. In addition to improving image quality, this path length regularizer yields the additional benefit that the generator becomes significantly easier to invert. This makes it possible to reliably attribute a generated image to a particular network. We furthermore visualize how well the generator utilizes its output resolution, and identify a capacity problem, motivating us to train larger models for additional quality improvements. Overall, our improved model redefines the state of the art in unconditional image modeling, both in terms of existing distribution quality metrics as well as perceived image quality.

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.

组织病理学分析是对癌前病变诊断的本金标准。从数字图像自动组织病理学分类的目标需要监督培训，这需要大量的专家注释，这可能是昂贵且耗时的收集。同时，精确分类从全幻灯片裁剪的图像斑块对于基于标准滑动窗口的组织病理学幻灯片分类方法是必不可少的。为了减轻这些问题，我们提出了一个精心设计的条件GaN模型，即hostogan，用于在类标签上合成现实组织病理学图像补丁。我们还研究了一种新颖的合成增强框架，可选择地添加由我们提出的HADOGAN生成的新的合成图像补丁，而不是直接扩展与合成图像的训练集。通过基于其指定标签的置信度和实际标记图像的特征相似性选择合成图像，我们的框架为合成增强提供了质量保证。我们的模型在两个数据集上进行评估：具有有限注释的宫颈组织病理学图像数据集，以及具有转移性癌症的淋巴结组织病理学图像的另一个数据集。在这里，我们表明利用具有选择性增强的组织产生的图像导致对宫颈组织病理学和转移性癌症数据集分别的分类性能（分别为6.7％和2.8％）的显着和一致性。

Trying to capture the sample-label relationship, conditional generative models often end up inheriting the spurious correlation in the training dataset, giving label-conditional distributions that are severely imbalanced in another latent attribute. To mitigate such undesirable correlations engraved into generative models, which we call spurious causality, we propose a general two-step strategy. (a) Fairness Intervention (FI): Emphasize the minority samples that are hard to be generated due to the spurious correlation in the training dataset. (b) Corrective Sampling (CS): Filter the generated samples explicitly to follow the desired label-conditional latent attribute distribution. We design the fairness intervention for various degrees of supervision on the spurious attribute, including unsupervised, weakly-supervised, and semi-supervised scenarios. Our experimental results show that the proposed FICS can successfully resolve the spurious correlation in generated samples on various datasets.