This work introduces a model that can recognize objects in images even if no training data is available for the object class. The only necessary knowledge about unseen visual categories comes from unsupervised text corpora. Unlike previous zero-shot learning models, which can only differentiate between unseen classes, our model can operate on a mixture of seen and unseen classes, simultaneously obtaining state of the art performance on classes with thousands of training images and reasonable performance on unseen classes. This is achieved by seeing the distributions of words in texts as a semantic space for understanding what objects look like. Our deep learning model does not require any manually defined semantic or visual features for either words or images. Images are mapped to be close to semantic word vectors corresponding to their classes, and the resulting image embeddings can be used to distinguish whether an image is of a seen or unseen class. We then use novelty detection methods to differentiate unseen classes from seen classes. We demonstrate two novelty detection strategies; the first gives high accuracy on unseen classes, while the second is conservative in its prediction of novelty and keeps the seen classes' accuracy high.
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广义零射击学习(GZSL)旨在培训一个模型,以在某些输出类别在监督学习过程中未知的情况下对数据样本进行分类。为了解决这一具有挑战性的任务,GZSL利用可见的(源)和看不见的(目标)类的语义信息来弥合所见类和看不见的类之间的差距。自引入以来,已经制定了许多GZSL模型。在这篇评论论文中,我们介绍了有关GZSL的全面评论。首先,我们提供了GZSL的概述,包括问题和挑战。然后,我们为GZSL方法介绍了分层分类,并讨论了每个类别中的代表性方法。此外,我们讨论了GZSL的可用基准数据集和应用程序,以及有关研究差距和未来研究方向的讨论。
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Despite significant progress in object categorization, in recent years, a number of important challenges remain; mainly, the ability to learn from limited labeled data and to recognize object classes within large, potentially open, set of labels. Zero-shot learning is one way of addressing these challenges, but it has only been shown to work with limited sized class vocabularies and typically requires separation between supervised and unsupervised classes, allowing former to inform the latter but not vice versa. We propose the notion of vocabulary-informed learning to alleviate the above mentioned challenges and address problems of supervised, zero-shot, generalized zero-shot and open set recognition using a unified framework. Specifically, we propose a weighted maximum margin framework for semantic manifold-based recognition that incorporates distance constraints from (both supervised and unsupervised) vocabulary atoms. Distance constraints ensure that labeled samples are projected closer to their correct prototypes, in the embedding space, than to others. We illustrate that resulting model shows improvements in supervised, zero-shot, generalized zero-shot, and large open set recognition, with up to 310K class vocabulary on Animal with Attributes and ImageNet datasets.
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We study the problem of object recognition for categories for which we have no training examples, a task also called zero-data or zero-shot learning. This situation has hardly been studied in computer vision research, even though it occurs frequently; the world contains tens of thousands of different object classes, and image collections have been formed and suitably annotated for only a few of them. To tackle the problem, we introduce attribute-based classification: Objects are identified based on a high-level description that is phrased in terms of semantic attributes, such as the object's color or shape. Because the identification of each such property transcends the specific learning task at hand, the attribute classifiers can be prelearned independently, for example, from existing image data sets unrelated to the current task. Afterward, new classes can be detected based on their attribute representation, without the need for a new training phase. In this paper, we also introduce a new data set, Animals with Attributes, of over 30,000 images of 50 animal classes, annotated with 85 semantic attributes. Extensive experiments on this and two more data sets show that attribute-based classification indeed is able to categorize images without access to any training images of the target classes.
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Modern visual recognition systems are often limited in their ability to scale to large numbers of object categories. This limitation is in part due to the increasing difficulty of acquiring sufficient training data in the form of labeled images as the number of object categories grows. One remedy is to leverage data from other sources -such as text data -both to train visual models and to constrain their predictions. In this paper we present a new deep visual-semantic embedding model trained to identify visual objects using both labeled image data as well as semantic information gleaned from unannotated text. We demonstrate that this model matches state-of-the-art performance on the 1000-class ImageNet object recognition challenge while making more semantically reasonable errors, and also show that the semantic information can be exploited to make predictions about tens of thousands of image labels not observed during training. Semantic knowledge improves such zero-shot predictions achieving hit rates of up to 18% across thousands of novel labels never seen by the visual model.
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零射击动作识别是识别无视觉示例的识别性类别的任务,只有在没有看到看到的类别的seman-tic嵌入方式。问题可以看作是学习一个函数,该函数可以很好地讲述不见的阶级实例,而不会在类之间失去歧视。神经网络可以模拟视觉类别之间的复杂边界,从而将其作为监督模型的成功范围。但是,这些高度专业化的类边界可能不会从看不见的班级转移到看不见的类别。在本文中,我们提出了基于质心的表示,该表示将视觉和语义表示,同时考虑所有训练样本,通过这种方式,对看不见的课程的实例很好。我们使用强化学习对群集进行优化,这对我们的工作方法表明了至关重要的。我们称提出的甲壳类动物的命名为Claster,并观察到它在所有标准数据集中始终超过最先进的方法,包括UCF101,HMDB51和奥运会运动;在Thestandard Zero-shot评估和广义零射击学习中。此外,我们表明我们的模型在图像域也可以进行com的性能,在许多设置中表现出色。
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监督学习方法可以在存在大量标记数据的情况下解决给定的问题。但是,涵盖所有目标类的数据集的采集通常需要昂贵且耗时的手动标签。零击学习模型能够通过利用其语义信息来对看不见的概念进行分类。本研究通过使用非线性声音 - 语义投影介绍了图像嵌入作为有关零击音频分类的附带信息。我们从开放图像数据集中提取语义图像表示形式,并使用不同域中的语义信息在音频集的音频子集上评估模型的性能;图像,音频和文字。我们证明,图像嵌入可以用作语义信息来执行零击音频分类。实验结果表明,图像和文本嵌入式单独和一起显示相似的性能。我们还从测试样品中计算出语义声嵌入,以提供性能的上限。结果表明,分类性能对测试和训练类之间的语义关系以及文本和图像嵌入之间的语义关系高度敏感,当时可见和看不见的类在语义上相似时,可以直至语义声学嵌入。
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机器学习模型通常会遇到与训练分布不同的样本。无法识别分布(OOD)样本,因此将该样本分配给课堂标签会显着损害模​​型的可靠性。由于其对在开放世界中的安全部署模型的重要性,该问题引起了重大关注。由于对所有可能的未知分布进行建模的棘手性,检测OOD样品是具有挑战性的。迄今为止,一些研究领域解决了检测陌生样本的问题,包括异常检测,新颖性检测,一级学习,开放式识别识别和分布外检测。尽管有相似和共同的概念,但分别分布,开放式检测和异常检测已被独立研究。因此,这些研究途径尚未交叉授粉,创造了研究障碍。尽管某些调查打算概述这些方法,但它们似乎仅关注特定领域,而无需检查不同领域之间的关系。这项调查旨在在确定其共同点的同时,对各个领域的众多著名作品进行跨域和全面的审查。研究人员可以从不同领域的研究进展概述中受益,并协同发展未来的方法。此外,据我们所知,虽然进行异常检测或单级学习进行了调查,但没有关于分布外检测的全面或最新的调查,我们的调查可广泛涵盖。最后,有了统一的跨域视角,我们讨论并阐明了未来的研究线,打算将这些领域更加紧密地融为一体。
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虽然对2D图像的零射击学习(ZSL)进行了许多研究,但其在3D数据中的应用仍然是最近且稀缺的,只有几种方法限于分类。我们在3D数据上介绍了ZSL和广义ZSL(GZSL)的第一代生成方法,可以处理分类,并且是第一次语义分割。我们表明它达到或胜过了INTEMNET40对归纳ZSL和归纳GZSL的ModelNet40分类的最新状态。对于语义分割,我们创建了三个基准,用于评估此新ZSL任务,使用S3DIS,Scannet和Semantickitti进行评估。我们的实验表明,我们的方法优于强大的基线,我们另外为此任务提出。
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Annotating words in a historical document image archive for word image recognition purpose demands time and skilled human resource (like historians, paleographers). In a real-life scenario, obtaining sample images for all possible words is also not feasible. However, Zero-shot learning methods could aptly be used to recognize unseen/out-of-lexicon words in such historical document images. Based on previous state-of-the-art method for zero-shot word recognition Pho(SC)Net, we propose a hybrid model based on the CTC framework (Pho(SC)-CTC) that takes advantage of the rich features learned by Pho(SC)Net followed by a connectionist temporal classification (CTC) framework to perform the final classification. Encouraging results were obtained on two publicly available historical document datasets and one synthetic handwritten dataset, which justifies the efficacy of Pho(SC)-CTC and Pho(SC)Net.
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跨模态散列(CMH)是跨模型近似最近邻搜索中最有前途的方法之一。大多数CMH解决方案理想地假设培训和测试集的标签是相同的。但是,通常违反假设,导致零拍摄的CMH问题。最近解决此问题的努力侧重于使用标签属性将知识转移到未见的类。但是,该属性与多模态数据的特征隔离。为了减少信息差距,我们介绍了一种名为LAEH的方法(嵌入零拍跨模型散列的标签属性)。 Laeh首先通过Word2Vec模型获取标签的初始语义属性向量,然后使用转换网络将它们转换为常见的子空间。接下来,它利用散列向量和特征相似矩阵来指导不同方式的特征提取网络。与此同时,Laeh使用属性相似性作为标签相似度的补充,以纠正标签嵌入和常见子空间。实验表明,Laeh优于相关代表零射和跨模态散列方法。
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Our experience of the world is multimodal -we see objects, hear sounds, feel texture, smell odors, and taste flavors. Modality refers to the way in which something happens or is experienced and a research problem is characterized as multimodal when it includes multiple such modalities. In order for Artificial Intelligence to make progress in understanding the world around us, it needs to be able to interpret such multimodal signals together. Multimodal machine learning aims to build models that can process and relate information from multiple modalities. It is a vibrant multi-disciplinary field of increasing importance and with extraordinary potential. Instead of focusing on specific multimodal applications, this paper surveys the recent advances in multimodal machine learning itself and presents them in a common taxonomy. We go beyond the typical early and late fusion categorization and identify broader challenges that are faced by multimodal machine learning, namely: representation, translation, alignment, fusion, and co-learning. This new taxonomy will enable researchers to better understand the state of the field and identify directions for future research.
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我们介绍了几个新的数据集即想象的A / O和Imagenet-R以及合成环境和测试套件,我们称为CAOS。 Imagenet-A / O允许研究人员专注于想象成剩余的盲点。由于追踪稳健的表示,以特殊创建了ImageNet-R,因为表示不再简单地自然,而是包括艺术和其他演绎。 Caos Suite由Carla Simulator构建,允许包含异常物体,可以创建可重复的合成环境和用于测试稳健性的场景。所有数据集都是为测试鲁棒性和衡量鲁棒性的衡量进展而创建的。数据集已用于各种其他作品中,以衡量其具有鲁棒性的自身进步,并允许切向进展,这些进展不会完全关注自然准确性。鉴于这些数据集,我们创建了几种旨在推进鲁棒性研究的新方法。我们以最大Logit的形式和典型程度的形式构建简单的基线,并以深度的形式创建新的数据增强方法,从而提高上述基准。最大Logit考虑Logit值而不是SoftMax操作后的值,而微小的变化会产生明显的改进。典型程分将输出分布与类的后部分布进行比较。我们表明,除了分段任务之外,这将提高对基线的性能。猜测可能在像素级别,像素的语义信息比类级信息的语义信息不太有意义。最后,新的Deepaulment的新增强技术利用神经网络在彻底不同于先前使用的传统几何和相机的转换的图像上创建增强。
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State-of-the-art computer vision systems are trained to predict a fixed set of predetermined object categories. This restricted form of supervision limits their generality and usability since additional labeled data is needed to specify any other visual concept. Learning directly from raw text about images is a promising alternative which leverages a much broader source of supervision. We demonstrate that the simple pre-training task of predicting which caption goes with which image is an efficient and scalable way to learn SOTA image representations from scratch on a dataset of 400 million (image, text) pairs collected from the internet. After pre-training, natural language is used to reference learned visual concepts (or describe new ones) enabling zero-shot transfer of the model to downstream tasks. We study the performance of this approach by benchmarking on over 30 different existing computer vision datasets, spanning tasks such as OCR, action recognition in videos, geo-localization, and many types of fine-grained object classification. The model transfers non-trivially to most tasks and is often competitive with a fully supervised baseline without the need for any dataset specific training. For instance, we match the accuracy of the original ResNet-50 on ImageNet zero-shot without needing to use any of the 1.28 million training examples it was trained on. We release our code and pre-trained model weights at https://github.com/OpenAI/CLIP.
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最近的方法表明,直接在大规模图像文本对集合上训练深神网络可以在各种识别任务上进行零拍传输。一个中心问题是如何将其推广到对象检测,这涉及本地化的非语义任务以及分类的语义任务。为了解决这个问题,我们引入了一种视觉嵌入对准方法,该方法将审计模型(例如夹子)(例如夹子)的概括能力传输到像Yolov5这样的对象检测器。我们制定了一个损耗函数,使我们能够将图像和文本嵌入在预审计的模型夹中对齐与检测器的修改语义预测头。通过这种方法,我们能够训练一个对象检测器,该对象检测器可以在可可,ILSVRC和视觉基因组零摄像机检测基准上实现最先进的性能。在推断期间,我们的模型可以适应以检测任何数量的对象类,而无需其他培训。我们还发现,标准对象检测缩放可以很好地传输到我们的方法,并在Yolov5模型和Yolov3模型的各种尺度上找到一致的改进。最后,我们开发了一种自我标记的方法,该方法可提供显着的分数改进,而无需额外的图像或标签。
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分布(OOD)检测对于确保机器学习系统的可靠性和安全性至关重要。例如,在自动驾驶中,我们希望驾驶系统在发现在训练时间中从未见过的异常​​场景或对象时,发出警报并将控件移交给人类,并且无法做出安全的决定。该术语《 OOD检测》于2017年首次出现,此后引起了研究界的越来越多的关注,从而导致了大量开发的方法,从基于分类到基于密度到基于距离的方法。同时,其他几个问题,包括异常检测(AD),新颖性检测(ND),开放式识别(OSR)和离群检测(OD)(OD),在动机和方法方面与OOD检测密切相关。尽管有共同的目标,但这些主题是孤立发展的,它们在定义和问题设定方面的细微差异通常会使读者和从业者感到困惑。在这项调查中,我们首先提出一个称为广义OOD检测的统一框架,该框架涵盖了上述五个问题,即AD,ND,OSR,OOD检测和OD。在我们的框架下,这五个问题可以看作是特殊情况或子任务,并且更容易区分。然后,我们通过总结了他们最近的技术发展来审查这五个领域中的每一个,特别关注OOD检测方法。我们以公开挑战和潜在的研究方向结束了这项调查。
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The process of learning good features for machine learning applications can be very computationally expensive and may prove difficult in cases where little data is available. A prototypical example of this is the one-shot learning setting, in which we must correctly make predictions given only a single example of each new class.In this paper, we explore a method for learning siamese neural networks which employ a unique structure to naturally rank similarity between inputs. Once a network has been tuned, we can then capitalize on powerful discriminative features to generalize the predictive power of the network not just to new data, but to entirely new classes from unknown distributions. Using a convolutional architecture, we are able to achieve strong results which exceed those of other deep learning models with near stateof-the-art performance on one-shot classification tasks.
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零拍分类问题的大多数现有算法通常依赖于类别之间基于属性的语义关系,以实现新型类别的分类而不观察其任何实例。但是,训练零拍分类模型仍然需要训练数据集中的每个类(甚至是实例)的属性标记,这也是昂贵的。为此,在本文中,我们提出了一个新的问题场景:“我们是否能够为新颖的属性探测器/分类器获得零射击学习,并使用它们自动注释数据集以进行标记效率?”基本上,仅给予一小组探测器,这些探测器都学会了识别一些手动注释的属性(即,所见属性),我们的目标是以零射学学习方式综合新颖属性的探测器。我们所提出的方法,零拍摄的属性(ZSLA),这是我们最好的知识中的第一个,通过应用SET操作首先将所看到的属性分解为基本属性,然后重新组合地解决这一新的研究问题。这些基本属性进入了新颖的属性。进行广泛的实验以验证我们合成探测器的能力,以便准确地捕获新颖性的语义,并与其他基线方法相比,在检测和定位方面表现出优越的性能。此外,在CALTECH-UCSD鸟类-200-2011 DataSet上使用仅32个属性,我们所提出的方法能够合成其他207个新颖的属性,而在由我们合成重新注释的数据集上培训的各种广义零拍分类算法属性探测器能够提供可比性的性能与手动地理注释有关的那些。
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在许多现实世界的医学图像分类设置中,我们无法访问所有可能的疾病类别的样本,而强大的系统有望在识别新型测试数据方面具有高性能。我们提出了一种通用的零射击学习(GZSL)方法,该方法使用自我监督学习(SSL)用于:1)选择不同疾病类别的锚定向量;2)训练功能生成器。我们的方法不需要类属性向量,这些向量可用于自然图像,但不适合医学图像。SSL确保锚向量代表每个类别。SSL还用于生成看不见类的合成特征。使用更简单的架构,我们的方法与基于SSL的最先进的GZSL方法匹配自然图像,并优于医学图像的所有方法。我们的方法足够适应于自然图像时可容纳类属性向量。
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Deep networks have produced significant gains for various visual recognition problems, leading to high impact academic and commercial applications. Recent work in deep networks highlighted that it is easy to generate images that humans would never classify as a particular object class, yet networks classify such images high confidence as that given class -deep network are easily fooled with images humans do not consider meaningful. The closed set nature of deep networks forces them to choose from one of the known classes leading to such artifacts. Recognition in the real world is open set, i.e. the recognition system should reject unknown/unseen classes at test time. We present a methodology to adapt deep networks for open set recognition, by introducing a new model layer, OpenMax, which estimates the probability of an input being from an unknown class. A key element of estimating the unknown probability is adapting Meta-Recognition concepts to the activation patterns in the penultimate layer of the network. Open-Max allows rejection of "fooling" and unrelated open set images presented to the system; OpenMax greatly reduces the number of obvious errors made by a deep network. We prove that the OpenMax concept provides bounded open space risk, thereby formally providing an open set recognition solution. We evaluate the resulting open set deep networks using pre-trained networks from the Caffe Model-zoo on ImageNet 2012 validation data, and thousands of fooling and open set images. The proposed OpenMax model significantly outperforms open set recognition accuracy of basic deep networks as well as deep networks with thresholding of SoftMax probabilities.
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