我们在视觉变压器上呈现整洁但有效的递归操作，可以提高参数利用而不涉及额外参数。这是通过在变压器网络的深度分享权重来实现的。所提出的方法可以只使用NA \“IVE递归操作来获得大量增益（〜2％），不需要对设计网络原理的特殊或复杂的知识，并引入训练程序的最小计算开销。减少额外的计算通过递归操作，同时保持卓越的准确性，我们通过递归层的多个切片组自行引入近似方法，这可以通过最小的性能损失将成本消耗降低10〜30％。我们称我们的模型切片递归变压器（SRET） ，这与高效视觉变压器的广泛的其他设计兼容。我们最好的模型在含有较少参数的同时，在最先进的方法中对Imagenet建立了重大改进。建议的切片递归操作使我们能够建立一个变压器超过100甚至1000层，仍然仍然小尺寸（13〜15米），以避免困难当模型尺寸太大时，IES在优化中。灵活的可扩展性显示出缩放和构建极深和大维视觉变压器的巨大潜力。我们的代码和模型可在https://github.com/szq0214/sret中找到。

Transformers have been recently adapted for large scale image classification, achieving high scores shaking up the long supremacy of convolutional neural networks. However the optimization of image transformers has been little studied so far. In this work, we build and optimize deeper transformer networks for image classification. In particular, we investigate the interplay of architecture and optimization of such dedicated transformers. We make two transformers architecture changes that significantly improve the accuracy of deep transformers. This leads us to produce models whose performance does not saturate early with more depth, for instance we obtain 86.5% top-1 accuracy on Imagenet when training with no external data, we thus attain the current SOTA with less FLOPs and parameters. Moreover, our best model establishes the new state of the art on Imagenet with Reassessed labels and Imagenet-V2 / match frequency, in the setting with no additional training data. We share our code and models 1 .

There still remains an extreme performance gap between Vision Transformers (ViTs) and Convolutional Neural Networks (CNNs) when training from scratch on small datasets, which is concluded to the lack of inductive bias. In this paper, we further consider this problem and point out two weaknesses of ViTs in inductive biases, that is, the spatial relevance and diverse channel representation. First, on spatial aspect, objects are locally compact and relevant, thus fine-grained feature needs to be extracted from a token and its neighbors. While the lack of data hinders ViTs to attend the spatial relevance. Second, on channel aspect, representation exhibits diversity on different channels. But the scarce data can not enable ViTs to learn strong enough representation for accurate recognition. To this end, we propose Dynamic Hybrid Vision Transformer (DHVT) as the solution to enhance the two inductive biases. On spatial aspect, we adopt a hybrid structure, in which convolution is integrated into patch embedding and multi-layer perceptron module, forcing the model to capture the token features as well as their neighboring features. On channel aspect, we introduce a dynamic feature aggregation module in MLP and a brand new "head token" design in multi-head self-attention module to help re-calibrate channel representation and make different channel group representation interacts with each other. The fusion of weak channel representation forms a strong enough representation for classification. With this design, we successfully eliminate the performance gap between CNNs and ViTs, and our DHVT achieves a series of state-of-the-art performance with a lightweight model, 85.68% on CIFAR-100 with 22.8M parameters, 82.3% on ImageNet-1K with 24.0M parameters. Code is available at https://github.com/ArieSeirack/DHVT.

视觉变压器（VITS）已成为各种视觉任务的流行结构和优于卷积神经网络（CNNS）。然而，这种强大的变形金机带来了巨大的计算负担。而这背后的基本障碍是排气的令牌到令牌比较。为了缓解这一点，我们深入研究Vit的模型属性，观察到VITS表现出稀疏关注，具有高令牌相似性。这直观地向我们介绍了可行的结构不可知的尺寸，令牌编号，以降低计算成本。基于这一探索，我们为香草vits提出了一种通用的自我切片学习方法，即坐下。具体而言，我们首先设计一种新颖的令牌减肥模块（TSM），可以通过动态令牌聚集来提高VIT的推理效率。不同于令牌硬滴，我们的TSM轻轻地集成了冗余令牌变成了更少的信息，可以在不切断图像中的鉴别性令牌关系的情况下动态缩放视觉注意。此外，我们介绍了一种简洁的密集知识蒸馏（DKD）框架，其密集地以柔性自动编码器方式传送无组织的令牌信息。由于教师和学生之间的结构类似，我们的框架可以有效地利用结构知识以获得更好的收敛性。最后，我们进行了广泛的实验来评估我们的坐姿。它展示了我们的方法可以通过1.7倍加速VITS，其精度下降可忽略不计，甚至在3.6倍上加速VITS，同时保持其性能的97％。令人惊讶的是，通过简单地武装LV-VIT与我们的坐线，我们在想象中实现了新的最先进的表现，超过了最近文学中的所有CNN和VITS。

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。

在本文中，我们通过利用视觉数据中的空间稀疏性提出了一种新的模型加速方法。我们观察到，视觉变压器中的最终预测仅基于最有用的令牌的子集，这足以使图像识别。基于此观察，我们提出了一个动态的令牌稀疏框架，以根据加速视觉变压器的输入逐渐和动态地修剪冗余令牌。具体而言，我们设计了一个轻量级预测模块，以估计给定当前功能的每个令牌的重要性得分。该模块被添加到不同的层中以层次修剪冗余令牌。尽管该框架的启发是我们观察到视觉变压器中稀疏注意力的启发，但我们发现自适应和不对称计算的想法可能是加速各种体系结构的一般解决方案。我们将我们的方法扩展到包括CNN和分层视觉变压器在内的层次模型，以及更复杂的密集预测任务，这些任务需要通过制定更通用的动态空间稀疏框架，并具有渐进性的稀疏性和非对称性计算，用于不同空间位置。通过将轻质快速路径应用于少量的特征，并使用更具表现力的慢速路径到更重要的位置，我们可以维护特征地图的结构，同时大大减少整体计算。广泛的实验证明了我们框架对各种现代体系结构和不同视觉识别任务的有效性。我们的结果清楚地表明，动态空间稀疏为模型加速提供了一个新的，更有效的维度。代码可从https://github.com/raoyongming/dynamicvit获得

视觉变压器的最新进展在基于点产生自我注意的新空间建模机制驱动的各种任务中取得了巨大成功。在本文中，我们表明，视觉变压器背后的关键要素，即输入自适应，远程和高阶空间相互作用，也可以通过基于卷积的框架有效地实现。我们介绍了递归封闭式卷积（$ \ textit {g}^\ textit {n} $ conv），该卷积{n} $ conv）与封闭的卷积和递归设计执行高阶空间交互。新操作是高度灵活和可定制的，它与卷积的各种变体兼容，并将自我注意的两阶相互作用扩展到任意订单，而无需引入大量额外的计算。 $ \ textit {g}^\ textit {n} $ conv可以用作插件模块，以改善各种视觉变压器和基于卷积的模型。根据该操作，我们构建了一个名为Hornet的新型通用视觉骨干家族。关于ImageNet分类，可可对象检测和ADE20K语义分割的广泛实验表明，大黄蜂的表现优于Swin变形金刚，并具有相似的整体体系结构和训练配置的明显边距。大黄蜂还显示出对更多训练数据和更大模型大小的有利可伸缩性。除了在视觉编码器中的有效性外，我们还可以将$ \ textit {g}^\ textit {n} $ conv应用于特定于任务的解码器，并始终通过较少的计算来提高密集的预测性能。我们的结果表明，$ \ textIt {g}^\ textit {n} $ conv可以成为视觉建模的新基本模块，可有效结合视觉变形金刚和CNN的优点。代码可从https://github.com/raoyongming/hornet获得

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.

Data mixing strategies (e.g., CutMix) have shown the ability to greatly improve the performance of convolutional neural networks (CNNs). They mix two images as inputs for training and assign them with a mixed label with the same ratio. While they are shown effective for vision transformers (ViTs), we identify a token fluctuation phenomenon that has suppressed the potential of data mixing strategies. We empirically observe that the contributions of input tokens fluctuate as forward propagating, which might induce a different mixing ratio in the output tokens. The training target computed by the original data mixing strategy can thus be inaccurate, resulting in less effective training. To address this, we propose a token-label alignment (TL-Align) method to trace the correspondence between transformed tokens and the original tokens to maintain a label for each token. We reuse the computed attention at each layer for efficient token-label alignment, introducing only negligible additional training costs. Extensive experiments demonstrate that our method improves the performance of ViTs on image classification, semantic segmentation, objective detection, and transfer learning tasks. Code is available at: https://github.com/Euphoria16/TL-Align.

由生物学进化的动机，本文通过类比与经过验证的实践进化算法（EA）相比，解释了视觉变压器的合理性，并得出了两者都具有一致的数学表述。然后，我们受到有效的EA变体的启发，我们提出了一个新型的金字塔饮食式主链，该主链仅包含拟议的\ emph {ea-ea-lase transformer}（eat）块，该块由三个残留零件组成，\ ie，\ emph {多尺度区域聚集}（msra），\ emph {global and local互动}（GLI）和\ emph {feed-forward Network}（ffn）模块，以分别建模多尺度，交互和个人信息。此外，我们设计了一个与变压器骨架对接的\ emph {与任务相关的头}（TRH），以更灵活地完成最终信息融合，并\ emph {reviv} a \ emph {调制变形MSA}（MD-MSA），以动态模型模型位置。关于图像分类，下游任务和解释性实验的大量定量和定量实验证明了我们方法比最新方法（SOTA）方法的有效性和优越性。 \例如，我们的手机（1.8m），微小（6.1m），小（24.3m）和基地（49.0m）型号达到了69.4、78.4、83.1和83.9的83.9 TOP-1仅在Imagenet-1 K上接受NAIVE训练的TOP-1食谱; Eatformer微型/小型/基本武装面具-R-CNN获得45.4/47.4/49.0盒AP和41.4/42.9/44.2掩膜可可检测，超过当代MPVIT-T，SWIN-T，SWIN-T和SWIN-S，而SWIN-S则是0.6/ 1.4/0.5盒AP和0.4/1.3/0.9掩码AP分别使用较少的拖鞋；我们的Eatformer-small/base在Upernet上获得了47.3/49.3 MIOU，超过Swin-T/S超过2.8/1.7。代码将在\ url {https：//https：//github.com/zhangzjn/eatformer}上提供。

变形金刚最近在计算机视觉社区中引起了极大的关注。然而，缺乏关于图像大小的自我注意力机制的可扩展性限制了它们在最先进的视觉骨架中的广泛采用。在本文中，我们介绍了一种高效且可扩展的注意模型，我们称之为多轴注意，该模型由两个方面组成：阻止局部和扩张的全球关注。这些设计选择允许仅具有线性复杂性的任意输入分辨率上进行全局本地空间相互作用。我们还通过有效地将我们提出的注意模型与卷积混合在一起，提出了一个新的建筑元素，因此，通过简单地在多个阶段重复基本的构建块，提出了一个简单的层次视觉主链，称为Maxvit。值得注意的是，即使在早期的高分辨率阶段，Maxvit也能够在整个网络中“看到”。我们证明了模型在广泛的视觉任务上的有效性。根据图像分类，Maxvit在各种设置下实现最先进的性能：没有额外的数据，Maxvit获得了86.5％的Imagenet-1K Top-1精度；使用Imagenet-21K预训练，我们的模型可实现88.7％的TOP-1精度。对于下游任务，麦克斯维特（Maxvit）作为骨架可在对象检测以及视觉美学评估方面提供有利的性能。我们还表明，我们提出的模型表达了ImageNet上强大的生成建模能力，这表明了Maxvit块作为通用视觉模块的优势潜力。源代码和训练有素的模型将在https://github.com/google-research/maxvit上找到。

The recently developed vision transformer (ViT) has achieved promising results on image classification compared to convolutional neural networks. Inspired by this, in this paper, we study how to learn multi-scale feature representations in transformer models for image classification. To this end, we propose a dual-branch transformer to combine image patches (i.e., tokens in a transformer) of different sizes to produce stronger image features. Our approach processes small-patch and large-patch tokens with two separate branches of different computational complexity and these tokens are then fused purely by attention multiple times to complement each other. Furthermore, to reduce computation, we develop a simple yet effective token fusion module based on cross attention, which uses a single token for each branch as a query to exchange information with other branches. Our proposed cross-attention only requires linear time for both computational and memory complexity instead of quadratic time otherwise. Extensive experiments demonstrate that our approach performs better than or on par with several concurrent works on vision transformer, in addition to efficient CNN models. For example, on the ImageNet1K dataset, with some architectural changes, our approach outperforms the recent DeiT by a large margin of 2% with a small to moderate increase in FLOPs and model parameters. Our source codes and models are available at https://github.com/IBM/CrossViT.

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.

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。

过去一年目睹了将变压器模块应用于视力问题的快速发展。虽然一些研究人员已经证明，基于变压器的模型享有有利的拟合数据能力，但仍然越来越多的证据，表明这些模型尤其在训练数据受到限制时遭受过度拟合。本文通过执行逐步操作来提供实证研究，逐步运输基于变压器的模型到基于卷积的模型。我们在过渡过程中获得的结果为改善视觉识别提供了有用的消息。基于这些观察，我们提出了一个名为VIRFormer的新架构，该体系结构从“视觉友好的变压器”中缩写。具有相同的计算复杂度，在想象集分类精度方面，VISFormer占据了基于变压器的基于卷积的模型，并且当模型复杂性较低或训练集较小时，优势变得更加重要。代码可在https://github.com/danczs/visformer中找到。

Masked image modeling (MIM) performs strongly in pre-training large vision Transformers (ViTs). However, small models that are critical for real-world applications cannot or only marginally benefit from this pre-training approach. In this paper, we explore distillation techniques to transfer the success of large MIM-based pre-trained models to smaller ones. We systematically study different options in the distillation framework, including distilling targets, losses, input, network regularization, sequential distillation, etc, revealing that: 1) Distilling token relations is more effective than CLS token- and feature-based distillation; 2) An intermediate layer of the teacher network as target perform better than that using the last layer when the depth of the student mismatches that of the teacher; 3) Weak regularization is preferred; etc. With these findings, we achieve significant fine-tuning accuracy improvements over the scratch MIM pre-training on ImageNet-1K classification, using all the ViT-Tiny, ViT-Small, and ViT-base models, with +4.2%/+2.4%/+1.4% gains, respectively. Our TinyMIM model of base size achieves 52.2 mIoU in AE20K semantic segmentation, which is +4.1 higher than the MAE baseline. Our TinyMIM model of tiny size achieves 79.6% top-1 accuracy on ImageNet-1K image classification, which sets a new record for small vision models of the same size and computation budget. This strong performance suggests an alternative way for developing small vision Transformer models, that is, by exploring better training methods rather than introducing inductive biases into architectures as in most previous works. Code is available at https://github.com/OliverRensu/TinyMIM.

Since the recent success of Vision Transformers (ViTs), explorations toward transformer-style architectures have triggered the resurgence of modern ConvNets. In this work, we explore the representation ability of DNNs through the lens of interaction complexities. We empirically show that interaction complexity is an overlooked but essential indicator for visual recognition. Accordingly, a new family of efficient ConvNets, named MogaNet, is presented to pursue informative context mining in pure ConvNet-based models, with preferable complexity-performance trade-offs. In MogaNet, interactions across multiple complexities are facilitated and contextualized by leveraging two specially designed aggregation blocks in both spatial and channel interaction spaces. Extensive studies are conducted on ImageNet classification, COCO object detection, and ADE20K semantic segmentation tasks. The results demonstrate that our MogaNet establishes new state-of-the-art over other popular methods in mainstream scenarios and all model scales. Typically, the lightweight MogaNet-T achieves 80.0\% top-1 accuracy with only 1.44G FLOPs using a refined training setup on ImageNet-1K, surpassing ParC-Net-S by 1.4\% accuracy but saving 59\% (2.04G) FLOPs.

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.

在最近的计算机视觉研究中，Vision Transformer（VIT）的出现迅速彻底改变了各种建筑设计工作：VIT使用自然语言处理中发现的自我注意力实现了最新的图像分类性能，而MLP-Mixer实现了使用简单多层感知器的竞争性能。相比之下，一些研究还表明，精心重新设计的卷积神经网络（CNN）可以实现与VIT相当的先进性能，而无需诉诸这些新想法。在这种背景下，越来越多的感应偏见适合计算机视觉。在这里，我们提出了Sequencer，这是VIT的一种新颖且具有竞争力的体系结构，可为这些问题提供新的看法。与VIT不同，音序器使用LSTM而不是自我发项层模型的远程依赖性。我们还提出了二维版本的音序器模块，其中LSTM分解为垂直和水平LSTM，以增强性能。尽管它很简单，但一些实验表明，Sequencer表现出色：Sequencer2d-L，具有54m参数，​​仅在Imagenet-1K上实现了84.6％的TOP-1精度。不仅如此，我们还表明它具有良好的可传递性和在双分辨率波段上具有强大的分辨率适应性。

最近，视觉变压器（VIT），具有自我关注（SA）作为事实上的成分，在计算机视觉社区中表现出很大的潜力。为了在效率和性能之间进行权衡，一组作品仅仅在本地补丁中执行SA操作，而全局上下文信息被放弃，这对于可视识别任务是不可或缺的。为了解决这个问题，随后的全球本地VITS在模型中以并行或替代方式将本地SA与全球范围内纳入本地SA。然而，令人遗憾地组合的局部和全局上下文可能存在各种视觉数据的冗余，并且每个层内的接收场是固定的。或者，更优雅的方式是全局和本地上下文可以自适应地贡献本身以适应不同的视觉数据。为实现这一目标，我们本文提出了一种新的Vit架构，称为NOMMER，可以动态提名视觉变压器中的协同全球本地背景。通过调查我们提出的NOMMER的工作模式，我们进一步探讨了哪些上下文信息。有益于这种“动态提名”机制，没有钟声和吹口哨，不仅可以在Imagenet上达到84.5％的前1个分类准确性，只有73米的参数，也显示了对致密预测任务的有希望的性能，即对象检测和语义分割。代码和模型将在〜\ url {https://github.com/nommer1125/nommer中公开可用。