场景文本识别（str）是图像和文本之间的重要桥梁，吸引了丰富的研究关注。虽然卷积神经网络（CNNS）在此任务中取得了显着的进展，但大多数现有工作都需要额外的模块（上下文建模模块）来帮助CNN捕获全局依赖项来解决归纳偏差并加强文本特征之间的关系。最近，该变压器已被提出作为通过自我关注机制的全球背景建模的有希望的网络，但在应用于识别时主要缺点是效率。我们提出了一个1-D拆分来解决复杂性的挑战，并用变压器编码器替换CNN，以减少对上下文建模模块的需求。此外，最近的方法使用冻结的初始嵌入来指导解码器对文本进行解码，导致精度损失。我们建议使用从变压器编码器中学到的学习学习的可读初始嵌入，使其自适应不同的输入图像。最重要的是，我们介绍了一个新颖的文本识别架构，名为基于变压器的文本识别器，其中包含三个阶段（转换，特征提取和预测）组成的初始嵌入指导（TRIG）。广泛的实验表明，我们的方法可以在文本识别基准上实现最先进的。

基于关注的编码器解码器框架广泛用于场景文本识别任务。然而，对于当前的最先进的（SOTA）方法，就输入文本图像的本地视觉和全局上下文信息的有效使用而言，存在改进的余地，以及场景之间的鲁棒相关性处理模块（编码器）和文本处理模块（解码器）。在本文中，我们提出了一种表示和相关性增强的编码器解码器框架（Rceed）来解决这些缺陷和断裂性能瓶颈。在编码器模块中，将本地视觉功能，全局上下文特征和位置信息进行对齐并融合以生成小型综合特征图。在解码器模块中，使用两种方法来增强场景和文本特征空间之间的相关性。 1）解码器初始化由从编码器导出的整体特征和全局瞥觉矢量引导。 2）通过多头一般注意力产生的富集瞥见载体的特征来帮助RNN迭代和每个时间步骤的字符预测。同时，我们还设计了一个LABRAMORM-DROPOUT LSTM单元，以改善模型的可变文本的概括。基准的广泛实验展示了在现场文本识别任务中的有利性能，尤其是不规则的性能。

多年来，场景文本识别（STR）一直是计算机视觉的积极研究主题。为了解决这个具有挑战性的问题，已经提出了许多创新的方法，并将语言知识纳入STR模型最近已成为一个显着的趋势。在这项工作中，我们首先从视觉变压器（VIT）的最新进展中汲取灵感来构建一个概念上简单而强大的视觉str模型，该模型建立在VIT和胜过以前的现场文本识别的先前最新模型，包括纯视觉模型和语言增强方法。为了整合语言知识，我们进一步提出了一种多粒性预测策略，以隐式方式将信息从语言模式注入模型，即NLP中广泛使用的子字表示（BPE和Wordpiece）被引入输出空间，除了传统的字符级别表示外，不采用独立语言模型（LM）。所得的算法（称为MGP-STR）能够将Str的性能包络提高到更高的水平。具体而言，它的平均识别精度在标准基准上达到93.35％。代码将很快发布。

文本识别是文档数字化的长期研究问题。现有的方法通常是基于CNN构建的，以用于图像理解，并为Char-Level文本生成而建立RNN。此外，通常需要另一种语言模型来提高整体准确性作为后处理步骤。在本文中，我们提出了一种使用预训练的图像变压器和文本变压器模型（即Trocr）提出的端到端文本识别方法，该模型利用了变压器体系结构，以实现图像理解和文字级级文本生成。TROR模型很简单，但有效，可以通过大规模合成数据进行预训练，并通过人体标记的数据集进行微调。实验表明，TROR模型的表现优于印刷，手写和场景文本识别任务上的当前最新模型。Trocr模型和代码可在\ url {https://aka.ms/trocr}上公开获得。

Transformer is a new kind of neural architecture which encodes the input data as powerful features via the attention mechanism. Basically, the visual transformers first divide the input images into several local patches and then calculate both representations and their relationship. Since natural images are of high complexity with abundant detail and color information, the granularity of the patch dividing is not fine enough for excavating features of objects in different scales and locations. In this paper, we point out that the attention inside these local patches are also essential for building visual transformers with high performance and we explore a new architecture, namely, Transformer iN Transformer (TNT). Specifically, we regard the local patches (e.g., 16×16) as "visual sentences" and present to further divide them into smaller patches (e.g., 4×4) as "visual words". The attention of each word will be calculated with other words in the given visual sentence with negligible computational costs. Features of both words and sentences will be aggregated to enhance the representation ability. Experiments on several benchmarks demonstrate the effectiveness of the proposed TNT architecture, e.g., we achieve an 81.5% top-1 accuracy on the ImageNet, which is about 1.7% higher than that of the state-of-the-art visual transformer with similar computational cost.

在现场文本识别中已经证明了语义信息。大多数现有方法倾向于将视觉和语义信息耦合到基于关注的解码器中。结果，语义特征的学习易于在训练集的有限词汇上具有偏差，这被称为词汇关系。在本文中，我们提出了一种新颖的视觉语义解耦网络（VSDN）来解决问题。我们的VSDN包含一个可视解码器（VD）和语义解码器（SD），以分别学习更纯度的视觉和语义特征表示。此外，语义编码器（SE）设计用于匹配SD，可以通过简单的单词校正任务通过额外的廉价大型词汇进行预先培训。因此，语义特征更加不偏并且精确地引导视觉特征对准并丰富最终字符表示。实验表明，我们的方法在标准基准上实现了最先进的或竞争力的结果，并且在培训集具有小尺寸的词汇量的情况下，在较大的余量下优于流行的基线。

Scene text spotting is of great importance to the computer vision community due to its wide variety of applications. Recent methods attempt to introduce linguistic knowledge for challenging recognition rather than pure visual classification. However, how to effectively model the linguistic rules in end-to-end deep networks remains a research challenge. In this paper, we argue that the limited capacity of language models comes from 1) implicit language modeling; 2) unidirectional feature representation; and 3) language model with noise input. Correspondingly, we propose an autonomous, bidirectional and iterative ABINet++ for scene text spotting. Firstly, the autonomous suggests enforcing explicitly language modeling by decoupling the recognizer into vision model and language model and blocking gradient flow between both models. Secondly, a novel bidirectional cloze network (BCN) as the language model is proposed based on bidirectional feature representation. Thirdly, we propose an execution manner of iterative correction for the language model which can effectively alleviate the impact of noise input. Finally, to polish ABINet++ in long text recognition, we propose to aggregate horizontal features by embedding Transformer units inside a U-Net, and design a position and content attention module which integrates character order and content to attend to character features precisely. ABINet++ achieves state-of-the-art performance on both scene text recognition and scene text spotting benchmarks, which consistently demonstrates the superiority of our method in various environments especially on low-quality images. Besides, extensive experiments including in English and Chinese also prove that, a text spotter that incorporates our language modeling method can significantly improve its performance both in accuracy and speed compared with commonly used attention-based recognizers.

计算机辅助医学图像分割已广泛应用于诊断和治疗，以获得靶器官和组织的形状和体积的临床有用信息。在过去的几年中，基于卷积神经网络（CNN）的方法（例如，U-Net）占主导地位，但仍遭受了不足的远程信息捕获。因此，最近的工作提出了用于医学图像分割任务的计算机视觉变压器变体，并获得了有希望的表现。这种变压器通过计算配对贴片关系来模拟远程依赖性。然而，它们促进了禁止的计算成本，尤其是在3D医学图像（例如，CT和MRI）上。在本文中，我们提出了一种称为扩张变压器的新方法，该方法在本地和全球范围内交替捕获的配对贴片关系进行自我关注。灵感来自扩张卷积核，我们以扩张的方式进行全球自我关注，扩大接收领域而不增加所涉及的斑块，从而降低计算成本。基于这种扩展变压器的设计，我们构造了一个用于3D医学图像分割的U形编码器解码器分层体系结构。 Synapse和ACDC数据集的实验表明，我们的D-Ager Model从头开始培训，以低计算成本从划痕训练，优于各种竞争力的CNN或基于变压器的分段模型，而不耗时的每训练过程。

在过去的几十年中，由于其在广泛的应用中，现场文本认可从学术界和实际用户获得了全世界的关注。尽管在光学字符识别方面取得了成就，但由于诸如扭曲或不规则布局等固有问题，现场文本识别仍然具有挑战性。大多数现有方法主要利用基于复发或卷积的神经网络。然而，虽然经常性的神经网络（RNN）通常由于顺序计算而遭受慢的训练速度，并且遇到消失的梯度或瓶颈，但CNN在复杂性和性能之间衡量折衷。在本文中，我们介绍了SAFL，一种基于自我关注的神经网络模型，具有场景文本识别的焦点损失，克服现有方法的限制。使用焦损而不是负值对数似然有助于模型更多地关注低频样本训练。此外，为应对扭曲和不规则文本，我们在传递到识别网络之前，我们利用空间变换（STN）来纠正文本。我们执行实验以比较拟议模型的性能与七个基准。数值结果表明，我们的模型实现了最佳性能。

视觉表示学习是解决各种视力问题的关键。依靠开创性的网格结构先验，卷积神经网络（CNN）已成为大多数深视觉模型的事实上的标准架构。例如，经典的语义分割方法通常采用带有编码器编码器体系结构的完全横向卷积网络（FCN）。编码器逐渐减少了空间分辨率，并通过更大的接受场来学习更多抽象的视觉概念。由于上下文建模对于分割至关重要，因此最新的努力一直集中在通过扩张（即极度）卷积或插入注意力模块来增加接受场。但是，基于FCN的体系结构保持不变。在本文中，我们旨在通过将视觉表示学习作为序列到序列预测任务来提供替代观点。具体而言，我们部署纯变压器以将图像编码为一系列贴片，而无需局部卷积和分辨率减少。通过在变压器的每一层中建立的全球环境，可以学习更强大的视觉表示形式，以更好地解决视力任务。特别是，我们的细分模型（称为分割变压器（SETR））在ADE20K上擅长（50.28％MIOU，这是提交当天测试排行榜中的第一个位置），Pascal环境（55.83％MIOU），并在CityScapes上达到竞争成果。此外，我们制定了一个分层局部全球（HLG）变压器的家族，其特征是窗户内的本地关注和跨窗户的全球性专注于层次结构和金字塔架构。广泛的实验表明，我们的方法在各种视觉识别任务（例如，图像分类，对象检测和实例分割和语义分割）上实现了吸引力的性能。

Scene text recognition (STR) involves the task of reading text in cropped images of natural scenes. Conventional models in STR employ convolutional neural network (CNN) followed by recurrent neural network in an encoder-decoder framework. In recent times, the transformer architecture is being widely adopted in STR as it shows strong capability in capturing long-term dependency which appears to be prominent in scene text images. Many researchers utilized transformer as part of a hybrid CNN-transformer encoder, often followed by a transformer decoder. However, such methods only make use of the long-term dependency mid-way through the encoding process. Although the vision transformer (ViT) is able to capture such dependency at an early stage, its utilization remains largely unexploited in STR. This work proposes the use of a transformer-only model as a simple baseline which outperforms hybrid CNN-transformer models. Furthermore, two key areas for improvement were identified. Firstly, the first decoded character has the lowest prediction accuracy. Secondly, images of different original aspect ratios react differently to the patch resolutions while ViT only employ one fixed patch resolution. To explore these areas, Pure Transformer with Integrated Experts (PTIE) is proposed. PTIE is a transformer model that can process multiple patch resolutions and decode in both the original and reverse character orders. It is examined on 7 commonly used benchmarks and compared with over 20 state-of-the-art methods. The experimental results show that the proposed method outperforms them and obtains state-of-the-art results in most benchmarks.

ous vision tasks without convolutions, where it can be used as a direct replacement for CNN backbones. (3) We validate PVT through extensive experiments, showing that it boosts the performance of many downstream tasks, including object detection, instance and semantic segmentation. For example, with a comparable number of parameters, PVT+RetinaNet achieves 40.4 AP on the COCO dataset, surpassing ResNet50+RetinNet (36.3 AP) by 4.1 absolute AP (see Figure 2). We hope that PVT could serve as an alternative and useful backbone for pixel-level predictions and facilitate future research.

Most recent semantic segmentation methods adopt a fully-convolutional network (FCN) with an encoderdecoder architecture. The encoder progressively reduces the spatial resolution and learns more abstract/semantic visual concepts with larger receptive fields. Since context modeling is critical for segmentation, the latest efforts have been focused on increasing the receptive field, through either dilated/atrous convolutions or inserting attention modules. However, the encoder-decoder based FCN architecture remains unchanged. In this paper, we aim to provide an alternative perspective by treating semantic segmentation as a sequence-to-sequence prediction task. Specifically, we deploy a pure transformer (i.e., without convolution and resolution reduction) to encode an image as a sequence of patches. With the global context modeled in every layer of the transformer, this encoder can be combined with a simple decoder to provide a powerful segmentation model, termed SEgmentation TRansformer (SETR). Extensive experiments show that SETR achieves new state of the art on ADE20K (50.28% mIoU), Pascal Context (55.83% mIoU) and competitive results on Cityscapes. Particularly, we achieve the first position in the highly competitive ADE20K test server leaderboard on the day of submission.

Image segmentation is often ambiguous at the level of individual image patches and requires contextual information to reach label consensus. In this paper we introduce Segmenter, a transformer model for semantic segmentation. In contrast to convolution-based methods, our approach allows to model global context already at the first layer and throughout the network. We build on the recent Vision Transformer (ViT) and extend it to semantic segmentation. To do so, we rely on the output embeddings corresponding to image patches and obtain class labels from these embeddings with a point-wise linear decoder or a mask transformer decoder. We leverage models pre-trained for image classification and show that we can fine-tune them on moderate sized datasets available for semantic segmentation. The linear decoder allows to obtain excellent results already, but the performance can be further improved by a mask transformer generating class masks. We conduct an extensive ablation study to show the impact of the different parameters, in particular the performance is better for large models and small patch sizes. Segmenter attains excellent results for semantic segmentation. It outperforms the state of the art on both ADE20K and Pascal Context datasets and is competitive on Cityscapes.

变压器是一种基于关注的编码器解码器架构，彻底改变了自然语言处理领域。灵感来自这一重大成就，最近在将变形式架构调整到计算机视觉（CV）领域的一些开创性作品，这已经证明了他们对各种简历任务的有效性。依靠竞争力的建模能力，与现代卷积神经网络相比在本文中，我们已经为三百不同的视觉变压器进行了全面的审查，用于三个基本的CV任务（分类，检测和分割），提出了根据其动机，结构和使用情况组织这些方法的分类。 。由于培训设置和面向任务的差异，我们还在不同的配置上进行了评估了这些方法，以便于易于和直观的比较而不是各种基准。此外，我们已经揭示了一系列必不可少的，但可能使变压器能够从众多架构中脱颖而出，例如松弛的高级语义嵌入，以弥合视觉和顺序变压器之间的差距。最后，提出了三个未来的未来研究方向进行进一步投资。

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.

由于长距离依赖性建模的能力，变压器在各种自然语言处理和计算机视觉任务中表现出令人印象深刻的性能。最近的进展证明，将这种变压器与基于CNN的语义图像分割模型相结合非常有前途。然而，目前还没有很好地研究了纯变压器的方法如何实现图像分割。在这项工作中，我们探索了语义图像分割的新框架，它是基于编码器 - 解码器的完全变压器网络（FTN）。具体地，我们首先提出金字塔组变压器（PGT）作为逐步学习分层特征的编码器，同时降低标准视觉变压器（VIT）的计算复杂性。然后，我们将特征金字塔变换器（FPT）提出了来自PGT编码器的多电平进行语义图像分割的多级别的语义级别和空间级信息。令人惊讶的是，这种简单的基线可以在多个具有挑战性的语义细分和面部解析基准上实现更好的结果，包括帕斯卡背景，ADE20K，Cocostuff和Celebamask-HQ。源代码将在https://github.com/br -dl/paddlevit上发布。

随着自我关注机制的发展，变压器模型已经在计算机视觉域中展示了其出色的性能。然而，从完全关注机制带来的大规模计算成为内存消耗的沉重负担。顺序地，记忆的限制降低了改善变压器模型的可能性。为了解决这个问题，我们提出了一种名为耦合器的新的记忆经济性注意力机制，它将注意力映射与两个子矩阵分成并从空间信息中生成对准分数。应用了一系列不同的尺度图像分类任务来评估模型的有效性。实验结果表明，在ImageNet-1K分类任务上，与常规变压器相比，耦合器可以显着降低28％的存储器消耗，同时访问足够的精度要求，并且在占用相同的内存占用时表达了0.92％。结果，耦合器可以用作视觉任务中的有效骨干，并提供关于研究人员注意机制的新颖视角。

视觉变压器在众多计算机视觉任务上表现出了巨大的成功。然而，由于计算复杂性和记忆足迹是二次的，因此其中心分量（软磁性注意力）禁止视觉变压器扩展到高分辨率图像。尽管在自然语言处理（NLP）任务中引入了线性注意以减轻类似问题，但直接将现有的线性注意力应用于视觉变压器可能不会导致令人满意的结果。我们研究了这个问题，发现与NLP任务相比，计算机视觉任务更多地关注本地信息。基于这一观察结果，我们提出了附近的关注，该关注引入了具有线性复杂性的视觉变压器的局部性偏见。具体而言，对于每个图像补丁，我们根据其相邻贴片测量的2D曼哈顿距离调整了注意力重量。在这种情况下，相邻的补丁比遥远的补丁会受到更大的关注。此外，由于我们的附近注意力要求令牌长度比特征维度大得多，以显示其效率优势，因此我们进一步提出了一个新的附近视觉变压器（VVT）结构，以减少特征维度而不脱离准确性。我们在CIFAR100，ImagEnet1k和ADE20K数据集上进行了广泛的实验，以验证我们方法的有效性。当输入分辨率增加时，与以前的基于变压器和基于卷积的网络相比，GFLOP的增长率较慢。特别是，我们的方法达到了最新的图像分类精度，其参数比以前的方法少50％。

提出了基于视觉变压器（VLT）的新型场景文本识别器。受NLP领域的Levenshtein Transformer的启发，提出的方法（命名为Levenshtein OCR和Short Levocr）探索了一种自动从裁剪自然图像中自动转录文本内容的替代方法。具体而言，我们将场景文本识别的问题视为迭代序列完善过程。由纯视觉模型产生的初始预测序列被编码并馈送到跨模式变压器中，以与视觉特征相互作用并融合，以逐渐近似地面真理。改进过程是通过两个基本字符级操作完成的：删除和插入，它们是通过模仿学习来学习的，并允许并行解码，动态长度变化和良好的解释性。定量实验清楚地表明，Levocr在标准基准上实现最新性能，定性分析验证了拟议的Levocr算法的有效性和优势。代码将很快发布。