Online media data, in the forms of images and videos, are becoming mainstream communication channels. However, recent advances in deep learning, particularly deep generative models, open the doors for producing perceptually convincing images and videos at a low cost, which not only poses a serious threat to the trustworthiness of digital information but also has severe societal implications. This motivates a growing interest of research in media tampering detection, i.e., using deep learning techniques to examine whether media data have been maliciously manipulated. Depending on the content of the targeted images, media forgery could be divided into image tampering and Deepfake techniques. The former typically moves or erases the visual elements in ordinary images, while the latter manipulates the expressions and even the identity of human faces. Accordingly, the means of defense include image tampering detection and Deepfake detection, which share a wide variety of properties. In this paper, we provide a comprehensive review of the current media tampering detection approaches, and discuss the challenges and trends in this field for future research.
translated by 谷歌翻译
文本VQA旨在回答需要了解图像中文本提示的问题。尽管现有的文本VQA方法取得了长足的进步,但它们的性能仍遭受了人类标记的问题解答(QA)对不足。但是,我们观察到,通常在现有数据集中没有完全利用场景文本 - 每个图像中只有一小部分文本参与了带注释的QA活动。这导致大量有用的信息浪费。为了解决这种缺陷,我们开发了一种新方法来通过明确利用每个图像的场景上下文中可用的现有文本来生成高质量和多样化的质量质量对。具体而言,我们建议,TAG是一种文本感知的视觉问题 - 答案生成的结构,该结构学会使用多模式变压器来生成有意义且准确的QA样品。该体系结构通过将生成的QA对与初始培训数据相结合,从而利用了未充满激光的场景文本信息,并增强了文本VQA模型的场景理解。对两个众所周知的Text-VQA基准(TextVQA和ST-VQA)的广泛实验结果表明,我们提议的标签有效地扩大了训练数据,有助于提高文本VQA性能而无需额外的标签努力。此外,我们的模型优于预先通过大规模数据进行训练的最先进方法。代码将公开可用。
translated by 谷歌翻译
我们提出了神经空间填充曲线(SFC),这是一种数据驱动的方法,用于推断一组图像的基于上下文的扫描顺序。像素的线性排序构成了许多应用程序的基础,例如用于图像的生成建模中的视频扰动,压缩和自动回归模型。现有的算法诉诸固定扫描算法,例如栅格扫描或希尔伯特扫描。取而代之的是,我们的工作使用基于图的神经网络从图像数据集中学习了像素的空间连贯的线性顺序。当图像与扫描线顺序一起遍历时,对所得神经SFC进行了优化,适用于适合下游任务的物镜。我们展示了在下游应用中使用神经SFC(例如图像压缩)的优势。代码和其他结果将在https://hywang66.github.io/publication/neuralsfc上提供。
translated by 谷歌翻译
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。
translated by 谷歌翻译
半监督对象检测(SSOD)的最新进展主要由基于一致性的伪标记方法驱动,用于图像分类任务,产生伪标签作为监控信号。然而,在使用伪标签时,缺乏考虑本地化精度和放大的类别不平衡,这两者都对于检测任务至关重要。在本文中,我们介绍了针对物体检测量身定制的确定性感知伪标签,可以有效地估计导出的伪标签的分类和定位质量。这是通过将传统定位转换为分类任务之后的传统定位来实现的。在分类和本地化质量分数上调节,我们动态调整用于为每个类别生成伪标签和重重损耗函数的阈值,以减轻类别不平衡问题。广泛的实验表明,我们的方法在Coco和Pascal VOC上的1-2%AP改善了最先进的SSOD性能,同时与大多数现有方法正交和互补。在有限的注释制度中,我们的方法可以通过从Coco标记的1-10%标记数据来改善监督基准。
translated by 谷歌翻译
Adversarial training, in which a network is trained on adversarial examples, is one of the few defenses against adversarial attacks that withstands strong attacks. Unfortunately, the high cost of generating strong adversarial examples makes standard adversarial training impractical on large-scale problems like ImageNet. We present an algorithm that eliminates the overhead cost of generating adversarial examples by recycling the gradient information computed when updating model parameters.Our "free" adversarial training algorithm achieves comparable robustness to PGD adversarial training on the CIFAR-10 and CIFAR-100 datasets at negligible additional cost compared to natural training, and can be 7 to 30 times faster than other strong adversarial training methods. Using a single workstation with 4 P100 GPUs and 2 days of runtime, we can train a robust model for the large-scale ImageNet classification task that maintains 40% accuracy against PGD attacks. The code is available at https://github.com/ashafahi/free_adv_train.
translated by 谷歌翻译
To reduce the significant redundancy in deep Convolutional Neural Networks (CNNs), most existing methods prune neurons by only considering statistics of an individual layer or two consecutive layers (e.g., prune one layer to minimize the reconstruction error of the next layer), ignoring the effect of error propagation in deep networks. In contrast, we argue that it is essential to prune neurons in the entire neuron network jointly based on a unified goal: minimizing the reconstruction error of important responses in the "final response layer" (FRL), which is the secondto-last layer before classification, for a pruned network to retrain its predictive power. Specifically, we apply feature ranking techniques to measure the importance of each neuron in the FRL, and formulate network pruning as a binary integer optimization problem and derive a closed-form solution to it for pruning neurons in earlier layers. Based on our theoretical analysis, we propose the Neuron Importance Score Propagation (NISP) algorithm to propagate the importance scores of final responses to every neuron in the network. The CNN is pruned by removing neurons with least importance, and then fine-tuned to retain its predictive power. NISP is evaluated on several datasets with multiple CNN models and demonstrated to achieve significant acceleration and compression with negligible accuracy loss.
translated by 谷歌翻译
Graph convolutional neural networks have shown significant potential in natural and histopathology images. However, their use has only been studied in a single magnification or multi-magnification with late fusion. In order to leverage the multi-magnification information and early fusion with graph convolutional networks, we handle different embedding spaces at each magnification by introducing the Multi-Scale Relational Graph Convolutional Network (MS-RGCN) as a multiple instance learning method. We model histopathology image patches and their relation with neighboring patches and patches at other scales (i.e., magnifications) as a graph. To pass the information between different magnification embedding spaces, we define separate message-passing neural networks based on the node and edge type. We experiment on prostate cancer histopathology images to predict the grade groups based on the extracted features from patches. We also compare our MS-RGCN with multiple state-of-the-art methods with evaluations on both source and held-out datasets. Our method outperforms the state-of-the-art on both datasets and especially on the classification of grade groups 2 and 3, which are significant for clinical decisions for patient management. Through an ablation study, we test and show the value of the pertinent design features of the MS-RGCN.
translated by 谷歌翻译
Machine learning (ML) has found broad applicability in quantum information science in topics as diverse as experimental design, state classification, and even studies on quantum foundations. Here, we experimentally realize an approach for defining custom prior distributions that are automatically tuned using ML for use with Bayesian quantum state estimation methods. Previously, researchers have looked to Bayesian quantum state tomography due to its unique advantages like natural uncertainty quantification, the return of reliable estimates under any measurement condition, and minimal mean-squared error. However, practical challenges related to long computation times and conceptual issues concerning how to incorporate prior knowledge most suitably can overshadow these benefits. Using both simulated and experimental measurement results, we demonstrate that ML-defined prior distributions reduce net convergence times and provide a natural way to incorporate both implicit and explicit information directly into the prior distribution. These results constitute a promising path toward practical implementations of Bayesian quantum state tomography.
translated by 谷歌翻译
Topological data analysis (TDA) is a branch of computational mathematics, bridging algebraic topology and data science, that provides compact, noise-robust representations of complex structures. Deep neural networks (DNNs) learn millions of parameters associated with a series of transformations defined by the model architecture, resulting in high-dimensional, difficult-to-interpret internal representations of input data. As DNNs become more ubiquitous across multiple sectors of our society, there is increasing recognition that mathematical methods are needed to aid analysts, researchers, and practitioners in understanding and interpreting how these models' internal representations relate to the final classification. In this paper, we apply cutting edge techniques from TDA with the goal of gaining insight into the interpretability of convolutional neural networks used for image classification. We use two common TDA approaches to explore several methods for modeling hidden-layer activations as high-dimensional point clouds, and provide experimental evidence that these point clouds capture valuable structural information about the model's process. First, we demonstrate that a distance metric based on persistent homology can be used to quantify meaningful differences between layers, and we discuss these distances in the broader context of existing representational similarity metrics for neural network interpretability. Second, we show that a mapper graph can provide semantic insight into how these models organize hierarchical class knowledge at each layer. These observations demonstrate that TDA is a useful tool to help deep learning practitioners unlock the hidden structures of their models.
translated by 谷歌翻译