对比性语言图像预训练(剪辑)已被证明可以学习具有出色传递性的视觉表示,从而实现了零击分类的有希望的准确性。为了进一步提高其下游性能,现有作品在剪辑上提出了其他可学习的模块,并通过几次训练集对其进行微调。但是,由此产生的额外培训成本和数据要求严重阻碍了模型部署和知识转移的效率。在本文中,我们引入了一种自由午餐的增强方法CALIP,以通过无参数注意模块来提高Clip的零拍摄性能。具体而言,我们指导视觉和文本表示相互交互,并通过注意探索跨模式的信息特征。由于预训练大大降低了两种方式之间的嵌入距离,因此我们在注意力中丢弃所有可学习的参数,并在双向更新多模式特征,从而使整个过程无参数且无培训。通过这种方式,图像与文本感知信号混合在一起,文本表示形式被视觉引导以获得更好的自适应零射击对齐。我们在14个数据集的各种基准上评估CALIP,用于2D图像和3D Point Cloud几乎没有分类,显示出一致的零弹性性能改进了夹子。基于此,我们进一步在Calip的注意模块中插入了少量线性层,并在少量射击设置下验证我们的鲁棒性,与现有方法相比,这也可以实现领先的性能。这些广泛的实验证明了我们的方法在有效增强夹子方面的优势。
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最近,通过对比视觉 - 语言预训练(CLIP)的零射击和少量学习已经在2D视觉识别上显示了鼓舞人心的性能,从而了解在开放词汇设置中将图像与其相应的文本匹配。然而,它仍然在探索中,是否通过2D中的大规模图像文本对预先训练的剪辑可以推广到3D识别。在本文中,我们通过提出引人点来识别这种设置是可行的,这在剪辑编码点云和3D类别文本之间进行对准。具体地,我们通过将点云投射到多视图深度映射而不呈现,并聚合视图零拍摄预测以实现从2D到3D的知识转移。首先,我们设计了一个视图间适配器,以更好地提取全局特征,并自适应地融合从3D到2D预培训的剪辑中学到的几次拍摄知识。只需在几次拍摄设置中微调轻量级适配器,可以在很大程度上提高要素的性能。此外,我们遵守CONTCLIP和古典3D监督网络之间的互补财产。通过简单的合奏,PointClip提高了基线的性能,甚至超越了最先进的模型。因此,PointClip是在低资源成本和数据制度下通过剪辑的有效3D点云理解的有希望的替代方案。我们在广泛采用的ModelNet10,ModelNet40和挑战ScanObjectnn上进行彻底的实验,以证明Pointclip的有效性。代码在https://github.com/zrrskywalker/pointclip发布。
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对比视力语言预训练(称为剪辑)为使用大型图像文本对学习视觉表示提供了新的范式。通过零拍知识转移,它在下游任务上表现出令人印象深刻的表现。为了进一步增强剪辑的适应能力,现有的方法提议微调额外的可学习模块,这大大改善了少量的性能,但引入了额外的培训时间和计算资源。在本文中,我们提出了一种无训练的适应方法,用于进行剪辑进行几个弹药分类,称为Tip-Adapter,该分类不仅继承了零拍剪辑的无训练优势,而且还与训练需要的那些相当的表现相当方法。 TIP-ADAPTER通过少数照片训练集通过键值缓存模型构造适配器,并更新通过功能检索中剪辑中编码的先验知识。最重要的是,可以通过对10 $ \ times $ \现有方法少的速度$ \ times $ $ \现有方法进行微调,这可以进一步提高Imagenet上的最先进。高效的。我们在11个数据集上进行了很少的射击分类实验,以证明我们提出的方法的优势。代码在https://github.com/gaopengcuhk/tip-adapter上发布。
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很少有射击分类需要深层神经网络才能仅从有限的培训图像中学习广义表示,这在低数据制度中很有挑战,但很重要。最近,基于剪辑的方法显示出有希望的很少的射击性能受益于对比的语言图像预训练。基于这一点,我们质疑大规模的预训练是否可以减轻少数数据的缺陷,并通过预测的知识帮助代表性学习。在本文中,我们提出了Como,这是对预培训模型的合作,该模型结合了来自各种培训范式的各种先验知识,以获得更好的几次学习。我们的科莫包括:剪辑的语言对比知识,迪诺的视力对抗性知识以及达尔 - E的语言基础知识。具体而言,科莫在两个方面工作:很少的数据扩展和多样化的知识合奏。首先,我们通过零摄影dall-e生成合成图像,以丰富少量训练数据,而无需任何人力。另一方面,我们引入了一个可学习的多知识适配器(MK-apapter),以适应剪辑和恐龙的预测。通过这种合作,COMO可以完全释放不同的预训练方法的潜力,并将其统一以进行几次分类。我们在11个数据集上进行了广泛的实验,以证明我们方法的优势和概括能力。
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作为剪辑的对比视觉语言预培训为通过使用大规模对比图像文本对提供了学习视觉表示的新范式。它显示了零击中知识转移到下游任务的令人印象深刻的性能。为了进一步增强剪辑的几次射击功能,提出的剪辑适配器提出微调轻量级残留功能适配器,并显着提高了几次拍摄分类的性能。但是,这样的过程仍然需要额外的培训和计算资源。在本文中,我们提出了\ textbf {t}下雨的cl \ textbf {ip} - \ textbf {适配器}(\ textbf {tip-adapter}),它不仅继承了剪辑的无训练优势,还可以相当地执行或甚至比剪辑适配器更好。提示 - 适配器不需要任何用于训练适配器的备份传播,而是通过从几次拍摄训练集构造的键值高速缓存模型创建权重。在这种非参数的方式中,提示适配器在没有任何训练的情况下获取良好的适配器权重,这既有效且有效。此外,可以通过微调这种适当的初始化适配器进一步提高尖端适配器的性能,仅用于具有超快速收敛速度的几个时期。我们对ImageNet和其他10个数据集进行了广泛的小型分类实验,以证明提出的提示适配器的优越性。代码将以\ URL {https://github.com/gaopengcuhk/tip-adapter}释放。
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随着大型预训练的Vison语言模型(如剪辑)的出现,可以通过及时调整来调整可转让表示形式。及时调整试图从存储在预训练的视觉模型的图像和文本编码器中的常识中探索有益信息,以探索下游任务。最近提出的名为“上下文优化”(COP)的方法将一组可学习的向量从语言侧引入文本提示符,而单独调整文本提示符则不会影响图像编码器的计算视觉特征,从而导致了次级优势。在本文中,我们通过学习文本提示并同时为文本和图像编码器提供双重模式提示调整范式。此外,为了使视觉提示更多地集中在目标视觉概念上,我们提出了类感知的视觉及时调整(CAVPT),该调整是通过在模板提示和视觉类别令牌嵌入的语言描述之间进行交叉注意来动态生成的。我们的方法提供了一种新的范式来调整大型预训练的视觉模型,并在8个数据集上进行了广泛的实验结果,证明了该方法的有效性。我们的代码在补充材料中可用。
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自动视觉解对我们多样化和开放的世界需要计算机视觉模型,以概括为特定任务的最小定制,类似于人类视力。计算机视觉基础型号培训,培训多样化,大型数据集,可以适应各种下游任务,对该任务来解决现实世界计算机视觉应用而言至关重要。虽然现有的视觉基础模型如剪辑,对齐和吴道2.0主要集中在映射图像和文本表示到跨模型共享表示,我们介绍了一台新的计算机视觉基础模型,佛罗伦萨,扩大粗糙的表示(现场)到精细(对象),从静态(图像)到动态(视频),以及从RGB到多个模态(标题,深度)。通过从Web级图像文本数据中纳入通用视觉语言表示,我们的佛罗伦萨模型可以很容易地适应各种计算机视觉任务,例如分类,检索,对象检测,VQA,图像标题,视频检索和动作识别。此外,佛罗伦萨在许多类型的转移学习中表现出出色的表现:全面采样的微调,线性探测,几次射击传输和用于新颖图像和物体的零拍摄传输。所有这些属性对于我们的视觉基础模型至关重要,以提供通用视觉任务。佛罗伦萨实现了新的最先进的导致44个代表性基准,例如Imagenet-1K零射击分类,最高1精度为83.74,最高5个精度为97.18,62.4地图上的Coco微调, 80.36在VQA上,动力学-600上的87.8。
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对比视觉语言预培训(剪辑)最近淹没了其可转让的视觉表现学习的关注。由大规模的图像文本对进行监督,剪辑能够对准配对的图像和文本,从而在开放词汇场景中进行零拍摄识别。然而,特定应用与通常预先训练的知识之间存在语义差距,这使得匹配子最优在下游任务上。在本文中,我们提出了VT-CLIP通过可视导向文本来增强视觉语言建模。具体而言,我们指导文本功能以自适应地探索图像上的信息区域,并通过跨关注的Machanism聚合视觉特征。以这种方式,视觉引导文本与图像变得更加语义相关,这极大地利益匹配过程。在几次拍摄的设置中,我们在11名知名分类数据集中评估我们的VT-CLIP,并进行实验广泛的消融研究,以证明VT-CLIP的有效性。代码将很快发布。
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The understanding capabilities of current state-of-the-art 3D models are limited by datasets with a small number of annotated data and a pre-defined set of categories. In its 2D counterpart, recent advances have shown that similar problems can be significantly alleviated by employing knowledge from other modalities, such as language. Inspired by this, leveraging multimodal information for 3D modality could be promising to improve 3D understanding under the restricted data regime, but this line of research is not well studied. Therefore, we introduce ULIP to learn a unified representation of image, text, and 3D point cloud by pre-training with object triplets from the three modalities. To overcome the shortage of training triplets, ULIP leverages a pre-trained vision-language model that has already learned a common visual and textual space by training with massive image-text pairs. Then, ULIP learns a 3D representation space aligned with the common image-text space, using a small number of automatically synthesized triplets. ULIP is agnostic to 3D backbone networks and can easily be integrated into any 3D architecture. Experiments show that ULIP effectively improves the performance of multiple recent 3D backbones by simply pre-training them on ShapeNet55 using our framework, achieving state-of-the-art performance in both standard 3D classification and zero-shot 3D classification on ModelNet40 and ScanObjectNN. ULIP also improves the performance of PointMLP by around 3% in 3D classification on ScanObjectNN, and outperforms PointCLIP by 28.8% on top-1 accuracy for zero-shot 3D classification on ModelNet40. Our code and pre-trained models will be released.
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Pre-training by numerous image data has become de-facto for robust 2D representations. In contrast, due to the expensive data acquisition and annotation, a paucity of large-scale 3D datasets severely hinders the learning for high-quality 3D features. In this paper, we propose an alternative to obtain superior 3D representations from 2D pre-trained models via Image-to-Point Masked Autoencoders, named as I2P-MAE. By self-supervised pre-training, we leverage the well learned 2D knowledge to guide 3D masked autoencoding, which reconstructs the masked point tokens with an encoder-decoder architecture. Specifically, we first utilize off-the-shelf 2D models to extract the multi-view visual features of the input point cloud, and then conduct two types of image-to-point learning schemes on top. For one, we introduce a 2D-guided masking strategy that maintains semantically important point tokens to be visible for the encoder. Compared to random masking, the network can better concentrate on significant 3D structures and recover the masked tokens from key spatial cues. For another, we enforce these visible tokens to reconstruct the corresponding multi-view 2D features after the decoder. This enables the network to effectively inherit high-level 2D semantics learned from rich image data for discriminative 3D modeling. Aided by our image-to-point pre-training, the frozen I2P-MAE, without any fine-tuning, achieves 93.4% accuracy for linear SVM on ModelNet40, competitive to the fully trained results of existing methods. By further fine-tuning on on ScanObjectNN's hardest split, I2P-MAE attains the state-of-the-art 90.11% accuracy, +3.68% to the second-best, demonstrating superior transferable capacity. Code will be available at https://github.com/ZrrSkywalker/I2P-MAE.
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现有的时间动作检测(TAD)方法依赖于大型培训数据,包括细分级注释,仅限于在推理期间单独识别先前看到的课程。为每类兴趣收集和注释一个大型培训集是昂贵的,因此无法计算。零射TAD(ZS-TAD)通过启用预训练的模型来识别任何看不见的动作类别来解决这一障碍。同时,ZS-TAD的调查大大降低,ZS-Tad也更具挑战性。受零摄像图像分类的成功的启发,我们旨在解决更复杂的TAD任务。一种直观的方法是将现成的建议探测器与剪辑样式分类集成。但是,由于顺序定位(例如,提案生成)和分类设计,它很容易进行定位误差传播。为了克服这个问题,在本文中,我们通过视觉提示(陈旧)提出了一种新型的零射击时间动作检测模型。这种新颖的设计通过破坏介于两者之间的错误传播途径来有效地消除了定位和分类之间的依赖性。我们进一步介绍了分类和定位之间的相互作用机制,以改善优化。对标准ZS-TAD视频基准测试的广泛实验表明,我们的陈旧的表现明显优于最先进的替代方案。此外,我们的模型还与最近的强大竞争对手相比,在受到监督的TAD上还能产生卓越的成果。 Stale的Pytorch实现可从https://github.com/sauradip/stale获得。
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Although significant progress has been made in few-shot learning, most of existing few-shot learning methods require supervised pre-training on a large amount of samples of base classes, which limits their generalization ability in real world application. Recently, large-scale self-supervised vision-language models (e.g., CLIP) have provided a new paradigm for transferable visual representation learning. However, the pre-trained VLPs may neglect detailed visual information that is difficult to describe by language sentences, but important for learning an effective classifier in few-shot classification. To address the above problem, we propose a new framework, named Semantic-guided Visual Adapting (SgVA), which can effectively extend vision-language pre-trained models to produce discriminative task-specific visual features by comprehensively using a vision-specific contrastive loss, a cross-modal contrastive loss, and an implicit knowledge distillation. The implicit knowledge distillation is designed to transfer the fine-grained cross-modal knowledge to guide the updating of the vision adapter. State-of-the-art results on 13 datasets demonstrate that the adapted visual features can well complement the cross-modal features to improve few-shot image classification.
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对比性语言图像预测在学习网络尺度数据的视觉文本联合表示方面取得了巨大的成功,这表明了各种图像任务的显着“零射”概括能力。但是,如何有效地将这种新的语言图像预处理方法扩展到视频域仍然是一个开放的问题。在这项工作中,我们提出了一种简单而有效的方法,该方法将预验证的语言图像模型直接适应视频识别,而不是从头开始预处理新模型。更具体地说,为了捕获沿时间维度框架的远距离依赖性,我们提出了一种跨框架注意机制,该机制明确地跨帧交换信息。这样的模块是轻量级的,可以无缝地插入验证的语言图像模型中。此外,我们提出了一个特定于视频的提示方案,该方案利用视频内容信息生成歧视性文本提示。广泛的实验表明,我们的方法是有效的,可以推广到不同的视频识别方案。特别是,在完全监督的设置下,我们的方法在Kinectics-400上获得了最高1的精度为87.1%,而与SWIN-L和Vivit-H相比,使用量少12倍。在零拍摄的实验中,我们的方法超过了当前的最新方法 +7.6%和 +14.9%,而在两个流行协议下,TOP-1的准确性。在少数拍摄的情况下,当标记的数据非常有限时,我们的方法优于先前的最佳方法 +32.1%和 +23.1%。代码和型号可在https://aka.ms/x-clip上找到
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Although existing multi-object tracking (MOT) algorithms have obtained competitive performance on various benchmarks, almost all of them train and validate models on the same domain. The domain generalization problem of MOT is hardly studied. To bridge this gap, we first draw the observation that the high-level information contained in natural language is domain invariant to different tracking domains. Based on this observation, we propose to introduce natural language representation into visual MOT models for boosting the domain generalization ability. However, it is infeasible to label every tracking target with a textual description. To tackle this problem, we design two modules, namely visual context prompting (VCP) and visual-language mixing (VLM). Specifically, VCP generates visual prompts based on the input frames. VLM joints the information in the generated visual prompts and the textual prompts from a pre-defined Trackbook to obtain instance-level pseudo textual description, which is domain invariant to different tracking scenes. Through training models on MOT17 and validating them on MOT20, we observe that the pseudo textual descriptions generated by our proposed modules improve the generalization performance of query-based trackers by large margins.
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在低标签制度中,解决图像的多标签识别(MLR)是许多现实世界应用的一项艰巨任务。最近的工作学会了文本和视觉空间之间的一致性,以补偿图像标签不足,但由于可用的MLR注释量有限,因此失去了准确性。在这项工作中,我们利用数百万辅助图像文本对预测的文本和视觉特征的牢固对齐,并提出双背景优化(dualCoop)作为部分标签MLR和零发射MLR的统一框架。 DualCoop用类名来编码正面和负面的上下文,作为语言输入的一部分(即提示)。由于DualCoop仅在验证的视觉语言框架上引入了非常轻松的开销,因此它可以迅速适应具有有限的注释甚至看不见的类别的多标签识别任务。对两个挑战性低标签设置的标准多标签识别基准测试的实验证明了我们方法比最新方法的优势。
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Contrastive Language-Image Pre-training (CLIP) has emerged as a simple yet effective way to train large-scale vision-language models. CLIP demonstrates impressive zero-shot classification and retrieval on diverse downstream tasks. However, to leverage its full potential, fine-tuning still appears to be necessary. Fine-tuning the entire CLIP model can be resource-intensive and unstable. Moreover, recent methods that aim to circumvent this need for fine-tuning still require access to images from the target distribution. In this paper, we pursue a different approach and explore the regime of training-free "name-only transfer" in which the only knowledge we possess about the downstream task comprises the names of downstream target categories. We propose a novel method, SuS-X, consisting of two key building blocks -- SuS and TIP-X, that requires neither intensive fine-tuning nor costly labelled data. SuS-X achieves state-of-the-art zero-shot classification results on 19 benchmark datasets. We further show the utility of TIP-X in the training-free few-shot setting, where we again achieve state-of-the-art results over strong training-free baselines. Code is available at https://github.com/vishaal27/SuS-X.
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参考图像分割旨在通过自然语言表达段段。在文本和图像之间的不同数据属性中,对网络充满良好的对齐文本和像素级别特征是具有挑战性的。现有方法使用借预制模型来促进学习,但分别从预磨料模型转移语言/视觉知识,忽略多模态对应信息。灵感来自最近对比语言 - 图像预测(剪辑)的预先推进(剪辑),在本文中,我们提出了一个端到端的剪辑驱动的参考图像分割框架(CRIS)。有效地转移多模态知识,克里斯语言解码和对比学习来实现文本到像素对齐的对比学习。更具体地,我们设计了一种视觉语言解码器,以将微粒语义信息从文本表示传播到每个像素级激活,这促进了两个模态之间的一致性。此外,我们呈现文本到像素对比学学习,明确强制执行类似于相关像素级别特征的文本特征,并与无关相似。三个基准数据集的实验结果表明,我们的拟议框架显着优于现有的性能而无需任何后处理。代码将被释放。
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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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Pre-trained vision-language models like CLIP have recently shown superior performances on various downstream tasks, including image classification and segmentation. However, in fine-grained image re-identification (ReID), the labels are indexes, lacking concrete text descriptions. Therefore, it remains to be determined how such models could be applied to these tasks. This paper first finds out that simply fine-tuning the visual model initialized by the image encoder in CLIP, has already obtained competitive performances in various ReID tasks. Then we propose a two-stage strategy to facilitate a better visual representation. The key idea is to fully exploit the cross-modal description ability in CLIP through a set of learnable text tokens for each ID and give them to the text encoder to form ambiguous descriptions. In the first training stage, image and text encoders from CLIP keep fixed, and only the text tokens are optimized from scratch by the contrastive loss computed within a batch. In the second stage, the ID-specific text tokens and their encoder become static, providing constraints for fine-tuning the image encoder. With the help of the designed loss in the downstream task, the image encoder is able to represent data as vectors in the feature embedding accurately. The effectiveness of the proposed strategy is validated on several datasets for the person or vehicle ReID tasks. Code is available at https://github.com/Syliz517/CLIP-ReID.
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从任务不足的预训练的深层模型中转移知识以进行下游任务是计算机视觉研究中的一个重要主题。随着计算能力的增长,我们现在拥有大规模的模型体系结构和数据量的开源视觉语言预培训模型。在这项研究中,我们专注于转移视力分类任务的知识。传统方法随机初始化线性分类器头进行视觉分类,但是它们将文本编码器的用法留为未发现的下游视觉识别任务。在本文中,我们修改了线性分类器的角色,并用对象类别的嵌入式语言表示替换分类器。这些语言表示是从视觉语言预训练模型的文本编码器初始化的,以进一步利用其良好的语言模型参数。实证研究表明,我们的方法提高了视频分类的性能和训练速度,模型的变化微不足道。特别是,我们的范式在动力学400上实现了87.3%的最新准确性。
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