变压器已经看到了自然语言处理和计算机视觉任务的前所未有的上升。但是,在音频任务中,由于音频波形的极大序列长度或在培训基于傅立叶特征时,它们是不可行的。在这项工作中,我们介绍了一个架构,Audiomer,在那里我们将1D残差网络与表演者的注意力结合起来,以实现使用原始音频波形的关键字在关键字中实现最先进的性能,优先于以前的所有方法,同时计算更便宜和参数效率。此外,我们的模型具有语音处理的实际优点,例如由于缺乏位置编码而在任意长的音频剪辑上推断。代码可在https://github.com/the-learning-machines/dautiomer获得
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We present in this paper a new architecture, named Convolutional vision Transformer (CvT), that improves Vision Transformer (ViT) in performance and efficiency by introducing convolutions into ViT to yield the best of both designs. This is accomplished through two primary modifications: a hierarchy of Transformers containing a new convolutional token embedding, and a convolutional Transformer block leveraging a convolutional projection. These changes introduce desirable properties of convolutional neural networks (CNNs) to the ViT architecture (i.e. shift, scale, and distortion invariance) while maintaining the merits of Transformers (i.e. dynamic attention, global context, and better generalization). We validate CvT by conducting extensive experiments, showing that this approach achieves state-of-the-art performance over other Vision Transformers and ResNets on ImageNet-1k, with fewer parameters and lower FLOPs. In addition, performance gains are maintained when pretrained on larger datasets (e.g. ImageNet-22k) and fine-tuned to downstream tasks. Pretrained on ImageNet-22k, our CvT-W24 obtains a top-1 accuracy of 87.7% on the ImageNet-1k val set. Finally, our results show that the positional encoding, a crucial component in existing Vision Transformers, can be safely removed in our model, simplifying the design for higher resolution vision tasks. Code will be released at https: //github.com/leoxiaobin/CvT.
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随着视觉变压器在多个计算机视觉任务中的成功应用之后,这些模型引起了信号处理社区的关注。这是因为信号通常表示为频谱图(例如通过离散的傅立叶变换),可以直接提供作为视觉变压器的输入。但是,天真地将变压器应用于频谱图是次优的。由于轴代表不同的尺寸,即频率和时间,因此我们认为一种更好的方法是将注意力集中在每个轴上。为此,我们提出了可分离的变压器(SEPTR),该体系结构以顺序使用两个变压器块,在同一时间间隔内首次访问令牌,第二个在同一频率箱内的代币。我们对三个基准数据集进行实验,表明我们的可分离体系结构的表现优于常规视觉变压器和其他最新方法。与标准变压器不同,SEPTR线性地缩放具有输入大小的可训练参数的数量,从而具有较低的内存足迹。我们的代码可在https://github.com/ristea/septr上作为开源。
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We present Multiscale Vision Transformers (MViT) for video and image recognition, by connecting the seminal idea of multiscale feature hierarchies with transformer models. Multiscale Transformers have several channel-resolution scale stages. Starting from the input resolution and a small channel dimension, the stages hierarchically expand the channel capacity while reducing the spatial resolution. This creates a multiscale pyramid of features with early layers operating at high spatial resolution to model simple low-level visual information, and deeper layers at spatially coarse, but complex, high-dimensional features. We evaluate this fundamental architectural prior for modeling the dense nature of visual signals for a variety of video recognition tasks where it outperforms concurrent vision transformers that rely on large scale external pre-training and are 5-10× more costly in computation and parameters. We further remove the temporal dimension and apply our model for image classification where it outperforms prior work on vision transformers. Code is available at: https: //github.com/facebookresearch/SlowFast.
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随着变压器作为语言处理的标准及其在计算机视觉方面的进步,参数大小和培训数据的数量相应地增长。许多人开始相信,因此,变形金刚不适合少量数据。这种趋势引起了人们的关注,例如:某些科学领域中数据的可用性有限,并且排除了该领域研究资源有限的人。在本文中,我们旨在通过引入紧凑型变压器来提出一种小规模学习的方法。我们首次表明,具有正确的尺寸,卷积令牌化,变压器可以避免在小数据集上过度拟合和优于最先进的CNN。我们的模型在模型大小方面具有灵活性,并且在获得竞争成果的同时,参数可能仅为0.28亿。当在CIFAR-10上训练Cifar-10,只有370万参数训练时,我们的最佳模型可以达到98%的准确性,这是与以前的基于变形金刚的模型相比,数据效率的显着提高,比其他变压器小于10倍,并且是15%的大小。在实现类似性能的同时,重新NET50。 CCT还表现优于许多基于CNN的现代方法,甚至超过一些基于NAS的方法。此外,我们在Flowers-102上获得了新的SOTA,具有99.76%的TOP-1准确性,并改善了Imagenet上现有基线(82.71%精度,具有29%的VIT参数)以及NLP任务。我们针对变压器的简单而紧凑的设计使它们更可行,可以为那些计算资源和/或处理小型数据集的人学习,同时扩展了在数据高效变压器中的现有研究工作。我们的代码和预培训模型可在https://github.com/shi-labs/compact-transformers上公开获得。
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We design a family of image classification architectures that optimize the trade-off between accuracy and efficiency in a high-speed regime. Our work exploits recent findings in attention-based architectures, which are competitive on highly parallel processing hardware. We revisit principles from the extensive literature on convolutional neural networks to apply them to transformers, in particular activation maps with decreasing resolutions. We also introduce the attention bias, a new way to integrate positional information in vision transformers.As a result, we propose LeVIT: a hybrid neural network for fast inference image classification. We consider different measures of efficiency on different hardware platforms, so as to best reflect a wide range of application scenarios. Our extensive experiments empirically validate our technical choices and show they are suitable to most architectures. Overall, LeViT significantly outperforms existing convnets and vision transformers with respect to the speed/accuracy tradeoff. For example, at 80% ImageNet top-1 accuracy, LeViT is 5 times faster than EfficientNet on CPU. We release the code at https: //github.com/facebookresearch/LeViT.
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我们呈现了基于纯变压器的视频分类模型,在图像分类中最近的近期成功进行了借鉴。我们的模型从输入视频中提取了时空令牌,然后由一系列变压器层编码。为了处理视频中遇到的令牌的长序列,我们提出了我们模型的几种有效的变体,它们将输入的空间和时间维构建。虽然已知基于变换器的模型只有在可用的大型训练数据集时才有效,但我们展示了我们如何在训练期间有效地规范模型,并利用预先训练的图像模型能够在相对小的数据集上训练。我们进行彻底的消融研究,并在包括动力学400和600,史诗厨房,东西的多个视频分类基准上实现最先进的结果,其中 - 基于深度3D卷积网络的现有方法表现出优先的方法。为了促进进一步的研究,我们在https://github.com/google-research/scenic/tree/main/scenic/projects/vivit发布代码
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视觉变压器(VIT)用作强大的视觉模型。与卷积神经网络不同,在前几年主导视觉研究,视觉变压器享有捕获数据中的远程依赖性的能力。尽管如此,任何变压器架构的组成部分,自我关注机制都存在高延迟和低效的内存利用,使其不太适合高分辨率输入图像。为了缓解这些缺点,分层视觉模型在非交错的窗口上局部使用自我关注。这种放松会降低输入尺寸的复杂性;但是,它限制了横窗相互作用,损害了模型性能。在本文中,我们提出了一种新的班次不变的本地注意层,称为查询和参加(QNA),其以重叠的方式聚集在本地输入,非常类似于卷积。 QNA背后的关键想法是介绍学习的查询,这允许快速高效地实现。我们通过将其纳入分层视觉变压器模型来验证我们的层的有效性。我们展示了速度和内存复杂性的改进,同时实现了与最先进的模型的可比准确性。最后,我们的图层尺寸尤其良好,窗口大小,需要高于X10的内存,而不是比现有方法更快。
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变形金刚在自然语言处理方面取得了巨大的成功。由于变压器中自我发挥机制的强大能力,研究人员为各种计算机视觉任务(例如图像识别,对象检测,图像分割,姿势估计和3D重建)开发了视觉变压器。本文介绍了有关视觉变形金刚的不同建筑设计和培训技巧(包括自我监督的学习)文献的全面概述。我们的目标是为开放研究机会提供系统的审查。
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事实证明,构象异构体在许多语音处理任务中都是有效的。它结合了使用卷积和使用自我注意的全球依赖性提取本地依赖的好处。受此启发,我们提出了一个更灵活,可解释和可自定义的编码器替代方案,分支机构,并在端到端语音处理中对各种远程依赖关系进行建模。在每个编码器层中,一个分支都采用自我注意事项或其变体来捕获远程依赖性,而另一个分支则利用带有卷积门控(CGMLP)的MLP模块来提取局部关系。我们对几种语音识别和口语理解基准进行实验。结果表明,我们的模型优于变压器和CGMLP。它还与构象异构体获得的最先进结果相匹配。此外,由于两分支结构,我们展示了减少计算的各种策略,包括在单个训练有素的模型中具有可变的推理复杂性的能力。合并分支的权重表明如何在不同层中使用本地和全球依赖性,从而使模型设计受益。
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在本文中,我们将多尺度视觉变压器(MVIT)作为图像和视频分类的统一架构,以及对象检测。我们提出了一种改进的MVIT版本,它包含分解的相对位置嵌入和残余汇集连接。我们以五种尺寸实例化此架构,并评估Imagenet分类,COCO检测和动力学视频识别,在此优先效果。我们进一步比较了MVITS的汇集注意力来窗口注意力机制,其中它在准确性/计算中优于后者。如果没有钟声,MVIT在3个域中具有最先进的性能:ImageNet分类的准确性为88.8%,Coco对象检测的56.1盒AP和动力学-400视频分类的86.1%。代码和模型将公开可用。
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Recently, neural networks purely based on attention were shown to address image understanding tasks such as image classification. These highperforming vision transformers are pre-trained with hundreds of millions of images using a large infrastructure, thereby limiting their adoption.In this work, we produce competitive convolution-free transformers by training on Imagenet only. We train them on a single computer in less than 3 days. Our reference vision transformer (86M parameters) achieves top-1 accuracy of 83.1% (single-crop) on ImageNet with no external data.More importantly, we introduce a teacher-student strategy specific to transformers. It relies on a distillation token ensuring that the student learns from the teacher through attention. We show the interest of this token-based distillation, especially when using a convnet as a teacher. This leads us to report results competitive with convnets for both Imagenet (where we obtain up to 85.2% accuracy) and when transferring to other tasks. We share our code and models.
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视觉变压器由于能够捕获图像中的长期依赖性的能力而成功地应用于图像识别任务。但是,变压器与现有卷积神经网络(CNN)之间的性能和计算成本仍然存在差距。在本文中,我们旨在解决此问题,并开发一个网络,该网络不仅可以超越规范变压器,而且可以超越高性能卷积模型。我们通过利用变压器来捕获长期依赖性和CNN来建模本地特征,从而提出了一个新的基于变压器的混合网络。此外,我们将其扩展为获得一个称为CMT的模型家族,比以前的基于卷积和基于变压器的模型获得了更好的准确性和效率。特别是,我们的CMT-S在ImageNet上获得了83.5%的TOP-1精度,而在拖鞋上的拖曳率分别比现有的DEIT和EficitiveNet小14倍和2倍。拟议的CMT-S还可以很好地概括CIFAR10(99.2%),CIFAR100(91.7%),花(98.7%)以及其他具有挑战性的视觉数据集,例如可可(44.3%地图),计算成本较小。
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While the Transformer architecture has become the de-facto standard for natural language processing tasks, its applications to computer vision remain limited. In vision, attention is either applied in conjunction with convolutional networks, or used to replace certain components of convolutional networks while keeping their overall structure in place. We show that this reliance on CNNs is not necessary and a pure transformer applied directly to sequences of image patches can perform very well on image classification tasks. When pre-trained on large amounts of data and transferred to multiple mid-sized or small image recognition benchmarks (ImageNet, CIFAR-100, VTAB, etc.), Vision Transformer (ViT) attains excellent results compared to state-of-the-art convolutional networks while requiring substantially fewer computational resources to train. 1
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我们使用无卷积的变压器架构提出了一种从未标记数据学习多式式表示的框架。具体而言,我们的视频音频文本变压器(Vatt)将原始信号作为输入提取,提取丰富的多式化表示,以使各种下游任务受益。我们使用多模式对比损失从头划线训练Vatt端到端,并通过视频动作识别,音频事件分类,图像分类和文本到视频检索的下游任务评估其性能。此外,我们通过共享三种方式之间的重量来研究模型 - 无话的单骨架变压器。我们表明,无卷积VATT优于下游任务中的最先进的Convnet架构。特别是,Vatt的视觉变压器在动力学-400上实现82.1%的高精度82.1%,在动力学-600,72.7%的动力学-700上的72.7%,以及时间的时间,新的记录,在避免受监督的预训练时,新的记录。通过从头划伤训练相同的变压器,转移到图像分类导致图像分类导致78.7%的ImageNet精度为64.7%,尽管视频和图像之间的域间差距,我们的模型概括了我们的模型。 Vatt的音雅音频变压器还通过在没有任何监督的预训练的情况下在Audioset上实现39.4%的地图来设置基于波形的音频事件识别的新记录。 Vatt的源代码是公开的。
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Astounding results from Transformer models on natural language tasks have intrigued the vision community to study their application to computer vision problems. Among their salient benefits, Transformers enable modeling long dependencies between input sequence elements and support parallel processing of sequence as compared to recurrent networks e.g., Long short-term memory (LSTM). Different from convolutional networks, Transformers require minimal inductive biases for their design and are naturally suited as set-functions. Furthermore, the straightforward design of Transformers allows processing multiple modalities (e.g., images, videos, text and speech) using similar processing blocks and demonstrates excellent scalability to very large capacity networks and huge datasets. These strengths have led to exciting progress on a number of vision tasks using Transformer networks. This survey aims to provide a comprehensive overview of the Transformer models in the computer vision discipline. We start with an introduction to fundamental concepts behind the success of Transformers i.e., self-attention, large-scale pre-training, and bidirectional feature encoding. We then cover extensive applications of transformers in vision including popular recognition tasks (e.g., image classification, object detection, action recognition, and segmentation), generative modeling, multi-modal tasks (e.g., visual-question answering, visual reasoning, and visual grounding), video processing (e.g., activity recognition, video forecasting), low-level vision (e.g., image super-resolution, image enhancement, and colorization) and 3D analysis (e.g., point cloud classification and segmentation). We compare the respective advantages and limitations of popular techniques both in terms of architectural design and their experimental value. Finally, we provide an analysis on open research directions and possible future works. We hope this effort will ignite further interest in the community to solve current challenges towards the application of transformer models in computer vision.
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最近的工作表明了计算机视觉应用的变压器的潜力。第一图像首先分区,然后将其用作注意机制的输入令牌。由于注意机构的昂贵二次成本,使用大的贴片尺寸,导致粗糙的全局相互作用,或者,替代地,仅在图像的局部区域上施加注意力,以牺牲远程相互作用为代价。在这项工作中,我们提出了一种方法,该方法允许在视觉变压器的早期层上允许粗糙的全局相互作用和细粒局部相互作用。在我们的方法的核心,是应用本地和全球注意层的应用。在本地注意层中,我们对每个补丁及其本地移位进行注意,导致几乎位于本地补丁,这些修补程序不绑定到单个特定位置。然后在全球注意层中使用这些实际的补丁。注意层进入本地和全局对应物的分离允许在贴片的数量中进行低计算成本,同时仍然支持已经在第一层处的数据相关的本地化,而不是其他可视变压器中的静态定位。我们的方法被证明优于基于卷积和变压器的图像分类方法,用于CIFAR10,CIFAR100和Imagenet。代码可在:https://github.com/shellysheynin/locally-sag-transformer。
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Recently, neural networks purely based on attention were shown to address image understanding tasks such as image classification. These highperforming vision transformers are pre-trained with hundreds of millions of images using a large infrastructure, thereby limiting their adoption.In this work, we produce competitive convolutionfree transformers trained on ImageNet only using a single computer in less than 3 days. Our reference vision transformer (86M parameters) achieves top-1 accuracy of 83.1% (single-crop) on ImageNet with no external data.We also introduce a teacher-student strategy specific to transformers. It relies on a distillation token ensuring that the student learns from the teacher through attention, typically from a convnet teacher. The learned transformers are competitive (85.2% top-1 acc.) with the state of the art on ImageNet, and similarly when transferred to other tasks. We will share our code and models.
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视觉变压器正在成为解决计算机视觉问题的强大工具。最近的技术还证明了超出图像域之外的变压器来解决许多与视频相关的任务的功效。其中,由于其广泛的应用,人类的行动识别是从研究界受到特别关注。本文提供了对动作识别的视觉变压器技术的首次全面调查。我们朝着这个方向分析并总结了现有文献和新兴文献,同时突出了适应变形金刚以进行动作识别的流行趋势。由于其专业应用,我们将这些方法统称为``动作变压器''。我们的文献综述根据其架构,方式和预期目标为动作变压器提供了适当的分类法。在动作变压器的背景下,我们探讨了编码时空数据,降低维度降低,框架贴片和时空立方体构造以及各种表示方法的技术。我们还研究了变压器层中时空注意的优化,以处理更长的序列,通常通过减少单个注意操作中的令牌数量。此外,我们还研究了不同的网络学习策略,例如自我监督和零局学习,以及它们对基于变压器的行动识别的相关损失。这项调查还总结了在具有动作变压器重要基准的评估度量评分方面取得的进步。最后,它提供了有关该研究方向的挑战,前景和未来途径的讨论。
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General perception systems such as Perceivers can process arbitrary modalities in any combination and are able to handle up to a few hundred thousand inputs. They achieve this generality by using exclusively global attention operations. This however hinders them from scaling up to the inputs sizes required to process raw high-resolution images or video. In this paper, we show that some degree of locality can be introduced back into these models, greatly improving their efficiency while preserving their generality. To scale them further, we introduce a self-supervised approach that enables learning dense low-dimensional positional embeddings for very large signals. We call the resulting model a Hierarchical Perceiver (HiP). In sum our contributions are: 1) scaling Perceiver-type models to raw high-resolution images and audio+video, 2) showing the feasibility of learning 1M+ positional embeddings from scratch using masked auto-encoding, 3) demonstrating competitive performance on raw data from ImageNet, AudioSet, PASCAL VOC, ModelNet40 and Kinetics datasets with the same exact, unchanged model and without specialized preprocessing or any tokenization.
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