The success of state-of-the-art deep neural networks heavily relies on the presence of large-scale labelled datasets, which are extremely expensive and time-consuming to annotate. This paper focuses on tackling semi-supervised part segmentation tasks by generating high-quality images with a pre-trained GAN and labelling the generated images with an automatic annotator. In particular, we formulate the annotator learning as a learning-to-learn problem. Given a pre-trained GAN, the annotator learns to label object parts in a set of randomly generated images such that a part segmentation model trained on these synthetic images with their predicted labels obtains low segmentation error on a small validation set of manually labelled images. We further reduce this nested-loop optimization problem to a simple gradient matching problem and efficiently solve it with an iterative algorithm. We show that our method can learn annotators from a broad range of labelled images including real images, generated images, and even analytically rendered images. Our method is evaluated with semi-supervised part segmentation tasks and significantly outperforms other semi-supervised competitors when the amount of labelled examples is extremely limited.

基于GAN的生成建模的进展是，社区的推动是为了发现超出图像生成和编辑任务的使用。特别是，最近的几项工作表明，可以重新用诸如零件分割的判别任务重新用来重新用，尤其是当训练数据有限时。但这些改进如何解决自我监督学习的最新进展情况？由此引起这种激励，我们提出了一种基于对比学习的替代方法，并比较它们对标准的几次射击部分分割基准的性能。我们的实验表明，不仅GAN的方法不提供显着的性能优势，它们的多步训练很复杂，几乎是数量级较慢，并且可以引入额外的偏差。这些实验表明，由使用对比学习训练的标准前馈网络捕获的生成模型的感应偏差，例如它们的解开形状和纹理的能力。这些实验表明，目前生成模型中存在的电感偏差，例如它们的解开形状和纹理的能力，通过使用对比学习训练的标准前馈网络充分捕获。

Jitendra Malik once said, "Supervision is the opium of the AI researcher". Most deep learning techniques heavily rely on extreme amounts of human labels to work effectively. In today's world, the rate of data creation greatly surpasses the rate of data annotation. Full reliance on human annotations is just a temporary means to solve current closed problems in AI. In reality, only a tiny fraction of data is annotated. Annotation Efficient Learning (AEL) is a study of algorithms to train models effectively with fewer annotations. To thrive in AEL environments, we need deep learning techniques that rely less on manual annotations (e.g., image, bounding-box, and per-pixel labels), but learn useful information from unlabeled data. In this thesis, we explore five different techniques for handling AEL.

带有像素天标签的注释图像是耗时和昂贵的过程。最近，DataSetGan展示了有希望的替代方案 - 通过利用一小组手动标记的GaN生成的图像来通过生成的对抗网络（GAN）来综合大型标记数据集。在这里，我们将DataSetGan缩放到ImageNet类别的规模。我们从ImageNet上训练的类条件生成模型中拍摄图像样本，并为所有1K类手动注释每个类的5张图像。通过在Biggan之上培训有效的特征分割架构，我们将Bigan转换为标记的DataSet生成器。我们进一步表明，VQGan可以类似地用作数据集生成器，利用已经注释的数据。我们通过在各种设置中标记一组8K实图像并在各种设置中评估分段性能来创建一个新的想象因基准。通过广泛的消融研究，我们展示了利用大型生成的数据集来培训在像素 - 明智的任务上培训不同的监督和自我监督的骨干模型的大增益。此外，我们证明，使用我们的合成数据集进行预培训，以改善在几个下游数据集上的标准Imagenet预培训，例如Pascal-VOC，MS-Coco，Citycapes和Chink X射线以及任务（检测，细分）。我们的基准将公开并维护一个具有挑战性的任务的排行榜。项目页面：https://nv-tlabs.github.io/big-dataseTgan/

去噪扩散概率模型最近获得了很多研究的关注，因为它们优于GAN，以及目前提供最先进的生成性能。扩散模型的卓越性能使它们在若干应用中为它们提供了吸引人的工具，包括尿素，超分辨率和语义编辑。在本文中，我们证明扩散模型也可以用作语义分割的仪器，特别是当标记数据稀缺时的设置中。特别地，对于几种预训练的扩散模型，我们研究了从执行反向扩散过程的马尔可夫步骤的网络的中间激活。我们表明这些激活有效地捕获了来自输入图像的语义信息，并且看起来是分割问题的优异像素级表示。基于这些观察，我们描述了一种简单的分段方法，即使仅提供了几种训练图像也可以工作。我们的方法显着优于若干数据集的现有替代品，以获得相同数量的人类监督。

语义分割在广泛的计算机视觉应用中起着基本作用，提供了全球对图像​​的理解的关键信息。然而，最先进的模型依赖于大量的注释样本，其比在诸如图像分类的任务中获得更昂贵的昂贵的样本。由于未标记的数据替代地获得更便宜，因此无监督的域适应达到了语义分割社区的广泛成功并不令人惊讶。本调查致力于总结这一令人难以置信的快速增长的领域的五年，这包含了语义细分本身的重要性，以及将分段模型适应新环境的关键需求。我们提出了最重要的语义分割方法;我们对语义分割的域适应技术提供了全面的调查;我们揭示了多域学习，域泛化，测试时间适应或无源域适应等较新的趋势;我们通过描述在语义细分研究中最广泛使用的数据集和基准测试来结束本调查。我们希望本调查将在学术界和工业中提供具有全面参考指导的研究人员，并有助于他们培养现场的新研究方向。

在社区中广泛调查了语义分割，其中最先进的技术基于监督模型。这些模型报告了前所未有的性能，以需要大量的高质量细分面具。为了获得这种注释是非常昂贵的并且特别是在需要像素级注释的语义分割中。在这项工作中，我们通过提出作为半监督语义细分的三级自我训练框架的整体解决方案来解决这个问题。我们技术的关键思想是提取伪掩模统计信息，以减少预测概率的不确定性，同时以多任务方式执行分段一致性。我们通过三级解决方案实现这一目标。首先，我们训练分割网络以产生粗糙的伪掩模，预测概率非常不确定。其次，我们使用一个多任务模型来减少伪掩模的不确定性，该模型强制利用数据丰富的数据统计信息。我们将采用现有方法与半监督语义分割的现有方法进行比较，并在广泛的实验中展示其最先进的性能。

Current state-of-the-art segmentation techniques for ocular images are critically dependent on large-scale annotated datasets, which are labor-intensive to gather and often raise privacy concerns. In this paper, we present a novel framework, called BiOcularGAN, capable of generating synthetic large-scale datasets of photorealistic (visible light and near-infrared) ocular images, together with corresponding segmentation labels to address these issues. At its core, the framework relies on a novel Dual-Branch StyleGAN2 (DB-StyleGAN2) model that facilitates bimodal image generation, and a Semantic Mask Generator (SMG) component that produces semantic annotations by exploiting latent features of the DB-StyleGAN2 model. We evaluate BiOcularGAN through extensive experiments across five diverse ocular datasets and analyze the effects of bimodal data generation on image quality and the produced annotations. Our experimental results show that BiOcularGAN is able to produce high-quality matching bimodal images and annotations (with minimal manual intervention) that can be used to train highly competitive (deep) segmentation models (in a privacy aware-manner) that perform well across multiple real-world datasets. The source code for the BiOcularGAN framework is publicly available at https://github.com/dariant/BiOcularGAN.

Recently, unsupervised learning has made impressive progress on various tasks. Despite the dominance of discriminative models, increasing attention is drawn to representations learned by generative models and in particular, Generative Adversarial Networks (GANs). Previous works on the interpretation of GANs reveal that GANs encode semantics in feature maps in a linearly separable form. In this work, we further find that GAN's features can be well clustered with the linear separability assumption. We propose a novel clustering algorithm, named KLiSH, which leverages the linear separability to cluster GAN's features. KLiSH succeeds in extracting fine-grained semantics of GANs trained on datasets of various objects, e.g., car, portrait, animals, and so on. With KLiSH, we can sample images from GANs along with their segmentation masks and synthesize paired image-segmentation datasets. Using the synthesized datasets, we enable two downstream applications. First, we train semantic segmentation networks on these datasets and test them on real images, realizing unsupervised semantic segmentation. Second, we train image-to-image translation networks on the synthesized datasets, enabling semantic-conditional image synthesis without human annotations.

在培训深层网络中进行部分分割的重要瓶颈是获得详细注释的成本。我们提出了一个框架，以利用粗糙标签，例如图形地面蒙版和关键点位置，这些位置容易用于某些类别以改善零件分割模型。一个关键的挑战是，这些注释是针对不同任务和不同的标签样式收集的，并且不能轻易地映射到零件标签上。为此，我们建议共同学习标签样式与部分分割模型之间的依赖关系，从而使我们能够利用来自不同标签的监督。为了评估我们的方法，我们在Caltech-UCSD鸟类和OID飞机数据集上开发了基准。我们的方法优于基于多任务学习，半监督学习和竞争方法的基准，这些方法依赖于手动设计的损失功能，以利用稀疏的supervision。

Recent work leverages the expressive power of generative adversarial networks (GANs) to generate labeled synthetic datasets. These dataset generation methods often require new annotations of synthetic images, which forces practitioners to seek out annotators, curate a set of synthetic images, and ensure the quality of generated labels. We introduce the HandsOff framework, a technique capable of producing an unlimited number of synthetic images and corresponding labels after being trained on less than 50 pre-existing labeled images. Our framework avoids the practical drawbacks of prior work by unifying the field of GAN inversion with dataset generation. We generate datasets with rich pixel-wise labels in multiple challenging domains such as faces, cars, full-body human poses, and urban driving scenes. Our method achieves state-of-the-art performance in semantic segmentation, keypoint detection, and depth estimation compared to prior dataset generation approaches and transfer learning baselines. We additionally showcase its ability to address broad challenges in model development which stem from fixed, hand-annotated datasets, such as the long-tail problem in semantic segmentation.

最近在图像编辑中找到了生成的对抗网络（GANS）。但是，大多数基于GaN的图像编辑方法通常需要具有用于训练的语义分段注释的大规模数据集，只提供高级控制，或者仅在不同图像之间插入。在这里，我们提出了EditGan，一种用于高质量，高精度语义图像编辑的新方法，允许用户通过修改高度详细的部分分割面罩，例如，为汽车前灯绘制新掩模来编辑图像。编辑登上的GAN框架上建立联合模型图像及其语义分割，只需要少数标记的示例，使其成为编辑的可扩展工具。具体地，我们将图像嵌入GaN潜在空间中，并根据分割编辑执行条件潜代码优化，这有效地修改了图像。算优化优化，我们发现在实现编辑的潜在空间中找到编辑向量。该框架允许我们学习任意数量的编辑向量，然后可以直接应用于交互式速率的其他图像。我们通过实验表明，EditGan可以用前所未有的细节和自由来操纵图像，同时保留完整的图像质量。我们还可以轻松地组合多个编辑并执行超出EditGan训练数据的合理编辑。我们在各种图像类型上展示编辑，并定量优于标准编辑基准任务的几种先前编辑方法。

In recent years, generative adversarial networks (GANs) have been an actively studied topic and shown to successfully produce high-quality realistic images in various domains. The controllable synthesis ability of GAN generators suggests that they maintain informative, disentangled, and explainable image representations, but leveraging and transferring their representations to downstream tasks is largely unexplored. In this paper, we propose to distill knowledge from GAN generators by squeezing and spanning their representations. We squeeze the generator features into representations that are invariant to semantic-preserving transformations through a network before they are distilled into the student network. We span the distilled representation of the synthetic domain to the real domain by also using real training data to remedy the mode collapse of GANs and boost the student network performance in a real domain. Experiments justify the efficacy of our method and reveal its great significance in self-supervised representation learning. Code is available at https://github.com/yangyu12/squeeze-and-span.

生成照片 - 现实图像，语义编辑和表示学习是高分辨率生成模型的许多潜在应用中的一些。最近在GAN的进展将它们建立为这些任务的绝佳选择。但是，由于它们不提供推理模型，因此使用GaN潜在空间无法在实际图像上完成诸如分类的图像编辑或下游任务。尽管培训了训练推理模型或设计了一种迭代方法来颠覆训练有素的发生器，但之前的方法是数据集（例如人类脸部图像）和架构（例如样式）。这些方法是非延伸到新型数据集或架构的。我们提出了一般框架，该框架是不可知的架构和数据集。我们的主要识别是，通过培训推断和生成模型在一起，我们允许它们彼此适应并收敛到更好的质量模型。我们的\ textbf {invang}，可逆GaN的简短，成功将真实图像嵌入到高质量的生成模型的潜在空间。这使我们能够执行图像修复，合并，插值和在线数据增强。我们展示了广泛的定性和定量实验。

无监督的域适应（UDA）旨在使源域上培训的模型适应到新的目标域，其中没有可用标记的数据。在这项工作中，我们调查从合成计算机生成的域的UDA的问题，以用于学习语义分割的类似但实际的域。我们提出了一种与UDA的一致性正则化方法结合的语义一致的图像到图像转换方法。我们克服了将合成图像转移到真实的图像的先前限制。我们利用伪标签来学习生成的图像到图像转换模型，该图像到图像转换模型从两个域上的语义标签接收额外的反馈。我们的方法优于最先进的方法，将图像到图像转换和半监督学习与相关域适应基准，即Citycapes和Synthia上的CutyCapes和Synthia进行了全面的学习。

For best performance, today's semantic segmentation methods use large and carefully labeled datasets, requiring expensive annotation budgets. In this work, we show that coarse annotation is a low-cost but highly effective alternative for training semantic segmentation models. Considering the urban scene segmentation scenario, we leverage cheap coarse annotations for real-world captured data, as well as synthetic data to train our model and show competitive performance compared with finely annotated real-world data. Specifically, we propose a coarse-to-fine self-training framework that generates pseudo labels for unlabeled regions of the coarsely annotated data, using synthetic data to improve predictions around the boundaries between semantic classes, and using cross-domain data augmentation to increase diversity. Our extensive experimental results on Cityscapes and BDD100k datasets demonstrate that our method achieves a significantly better performance vs annotation cost tradeoff, yielding a comparable performance to fully annotated data with only a small fraction of the annotation budget. Also, when used as pretraining, our framework performs better compared to the standard fully supervised setting.

深度神经网络在人类分析中已经普遍存在，增强了应用的性能，例如生物识别识别，动作识别以及人重新识别。但是，此类网络的性能通过可用的培训数据缩放。在人类分析中，对大规模数据集的需求构成了严重的挑战，因为数据收集乏味，廉价，昂贵，并且必须遵守数据保护法。当前的研究研究了\ textit {合成数据}的生成，作为在现场收集真实数据的有效且具有隐私性的替代方案。这项调查介绍了基本定义和方法，在生成和采用合成数据进行人类分析时必不可少。我们进行了一项调查，总结了当前的最新方法以及使用合成数据的主要好处。我们还提供了公开可用的合成数据集和生成模型的概述。最后，我们讨论了该领域的局限性以及开放研究问题。这项调查旨在为人类分析领域的研究人员和从业人员提供。

半监督语义分割的流行方法主要采用了使用卷积神经网络（CNN）（CNN）的统一网络模型，并在应用于输入或模型的小型扰动上实施模型预测的一致性。但是，这种学习范式受到a）基于CNN模型的学习能力有限； b）学习未标记数据的判别特征的能力有限； c）从整个图像中对全球和本地信息的学习有限。在本文中，我们提出了一种新型的半监督学习方法，称为Transformer-CNN队列（TCC），该方法由两个基于视觉变压器（VIT）的学生组成，另一种是基于CNN的学生。我们的方法巧妙地通过伪标记来纳入预测和异质特征空间上的多级一致性正则化，用于未标记的数据。首先，由于VIT学生的输入是图像贴片，因此特征地图提取了编码至关重要的类统计。为此，我们建议首先利用每个学生作为伪标签并生成类吸引功能（CF）映射的班级感知功能一致性蒸馏（CFCD）。然后，它通过学生之间的CF地图传输知识。其次，随着VIT学生对所有层具有更统一的表示，我们提出一致性感知的交叉蒸馏以在类像素方面的预测之间转移知识。我们在CityScapes和Pascal VOC 2012数据集上验证了TCC框架，该数据集大大优于现有的半监督方法。

Image segmentation is a key topic in image processing and computer vision with applications such as scene understanding, medical image analysis, robotic perception, video surveillance, augmented reality, and image compression, among many others. Various algorithms for image segmentation have been developed in the literature. Recently, due to the success of deep learning models in a wide range of vision applications, there has been a substantial amount of works aimed at developing image segmentation approaches using deep learning models. In this survey, we provide a comprehensive review of the literature at the time of this writing, covering a broad spectrum of pioneering works for semantic and instance-level segmentation, including fully convolutional pixel-labeling networks, encoder-decoder architectures, multi-scale and pyramid based approaches, recurrent networks, visual attention models, and generative models in adversarial settings. We investigate the similarity, strengths and challenges of these deep learning models, examine the most widely used datasets, report performances, and discuss promising future research directions in this area.

深度学习方法依赖于高质量的人类监督，这仍然昂贵，耗时和容易出错，特别是对于图像分割任务。在本文中，我们提出了一种用于自动综合成对的照片 - 现实图像和分割掩模的方法，以便使用前景背景分割网络。特别地，我们学习一种生成的对抗网络，其将图像分解为前景和背景层，并通过最大化生成的图像和潜在变量之间的互信息来避免微小分解。改进的分层GAN可以合成更高质量的数据集，可以从中学习更高性能的分段网络。此外，采用分割网络来稳定分层GAN的训练作为返回，其与层状导致进一步交替培训。关于各种单对象数据集的实验表明，与相关方法相比，我们的方法实现了竞争的发电质量和分割性能。