在本文中，我们考虑了从长时间的视频到几分钟的长视频进行分类的问题（例如，烹饪不同的食谱，烹饪不同的食谱，进行不同的家庭装修，创建各种形式的艺术和手工艺品）。准确地对这些活动进行分类，不仅需要识别构成任务的单个步骤，还需要捕获其时间依赖性。这个问题与传统的动作分类大不相同，在传统的动作分类中，模型通常在跨越几秒钟的视频上进行了优化，并且手动修剪以包含简单的原子动作。虽然步骤注释可以使模型的培训能够识别程序活动的各个步骤，但由于长时间视频中手动注释时间界的超级注释，因此该领域的现有大规模数据集不包括此类段标签。为了解决这个问题，我们建议通过利用文本知识库（Wikihow）的遥远监督来自动确定教学视频中的步骤，其中包括对执行各种复杂活动所需的步骤的详细描述。我们的方法使用语言模型来匹配视频中自动转录的语音，以在知识库中逐步描述。我们证明，经过训练的视频模型可以识别这些自动标记的步骤（无手动监督）产生了在四个下游任务上实现卓越的概括性能的表示：识别程序活动，步骤分类，步骤预测和以自我为中心的视频分类。

Timeyou have a little pressure you are cutting the wood readjusting the table saw I am using a roller sure you applied glue Figure 1: We describe an efficient approach to learn visual representations from misaligned and noisy narrations (bottom) automatically extracted from instructional videos (top). Our video representations are learnt from scratch without relying on any manually annotated visual dataset yet outperform all self-supervised and many fully-supervised methods on several video recognition benchmarks.

We introduce LaViLa, a new approach to learning video-language representations by leveraging Large Language Models (LLMs). We repurpose pre-trained LLMs to be conditioned on visual input, and finetune them to create automatic video narrators. Our auto-generated narrations offer a number of advantages, including dense coverage of long videos, better temporal synchronization of the visual information and text, and much higher diversity of text. The video-text embedding learned contrastively with these additional auto-generated narrations outperforms the previous state-of-the-art on multiple first-person and third-person video tasks, both in zero-shot and finetuned setups. Most notably, LaViLa obtains an absolute gain of 10.1% on EGTEA classification and 5.9% Epic-Kitchens-100 multi-instance retrieval benchmarks. Furthermore, LaViLa trained with only half the narrations from the Ego4D dataset outperforms baseline models trained on the full set, and shows positive scaling behavior on increasing pre-training data and model size.

Self-supervised learning has become increasingly important to leverage the abundance of unlabeled data available on platforms like YouTube. Whereas most existing approaches learn low-level representations, we propose a joint visual-linguistic model to learn high-level features without any explicit supervision. In particular, inspired by its recent success in language modeling, we build upon the BERT model to learn bidirectional joint distributions over sequences of visual and linguistic tokens, derived from vector quantization of video data and off-the-shelf speech recognition outputs, respectively. We use VideoBERT in numerous tasks, including action classification and video captioning. We show that it can be applied directly to openvocabulary classification, and confirm that large amounts of training data and cross-modal information are critical to performance. Furthermore, we outperform the state-of-theart on video captioning, and quantitative results verify that the model learns high-level semantic features.

Can we teach a robot to recognize and make predictions for activities that it has never seen before? We tackle this problem by learning models for video from text. This paper presents a hierarchical model that generalizes instructional knowledge from large-scale text corpora and transfers the knowledge to video. Given a portion of an instructional video, our model recognizes and predicts coherent and plausible actions multiple steps into the future, all in rich natural language. To demonstrate the capabilities of our model, we introduce the \emph{Tasty Videos Dataset V2}, a collection of 4022 recipes for zero-shot learning, recognition and anticipation. Extensive experiments with various evaluation metrics demonstrate the potential of our method for generalization, given limited video data for training models.

作为人类，我们通过我们所有的感官来驾驭世界，使用每个人从每个人纠正其他人。我们介绍了Merlot Reserve，一个模型，该模型是联合随着时间的推移而表示视频的模型 - 通过从音频，字幕和视频帧学习的新培训目标。给出了一个视频，我们用掩模令牌替换文本和音频的片段;该模型通过选择正确的蒙版片段来学习。我们的目标比替代方面更快地学习，并在规模上表现良好：我们预先逼近2000万YouTube视频。经验结果表明，Merlot Reserve学会通过所有组成模式的视频的强烈陈述。在FineTuned时，它在VCR和TVQA上为VCR和TVQA进行了新的最先进，优先于前勤工作分别为5％和7％。消融表明，两个任务都受益于音频预制 - 甚至录像机，围绕图像中心的QA任务（没有声音）。此外，我们的客观使开箱即用的预测，揭示了强大的多式联合致辞理解。在一个完全零拍摄的环境中，我们的模型在四个视频理解任务中获得竞争结果，甚至优于最近提出的定位推理（星）基准的监督方法。我们分析为什么包含音频导致更好的视觉语言表示，这表明未来研究的重要机会。我们通过讨论多式联运预测的道德和社会影响来得出结论。

Learning text-video embeddings usually requires a dataset of video clips with manually provided captions. However, such datasets are expensive and time consuming to create and therefore difficult to obtain on a large scale. In this work, we propose instead to learn such embeddings from video data with readily available natural language annotations in the form of automatically transcribed narrations. The contributions of this work are three-fold. First, we introduce HowTo100M: a large-scale dataset of 136 million video clips sourced from 1.22M narrated instructional web videos depicting humans performing and describing over 23k different visual tasks. Our data collection procedure is fast, scalable and does not require any additional manual annotation. Second, we demonstrate that a text-video embedding trained on this data leads to state-ofthe-art results for text-to-video retrieval and action localization on instructional video datasets such as YouCook2 or CrossTask. Finally, we show that this embedding transfers well to other domains: fine-tuning on generic Youtube videos (MSR-VTT dataset) and movies (LSMDC dataset) outperforms models trained on these datasets alone. Our dataset, code and models are publicly available [1]. * Equal contribution.

寻找特定任务说明的YouTube用户可能会花费很长时间浏览内容，以寻找与他们需求相匹配的正确视频。创建视觉摘要（视频的删节版本）为观众提供了快速概述，并大大减少了搜索时间。在这项工作中，我们专注于总结教学视频，这​​是视频摘要的探索领域。与通用视频相比，可以将教学视频解析为语义上有意义的细分，这些细分与所示任务的重要步骤相对应。现有的视频摘要数据集依靠手动框架级注释，使其主观且大小有限。为了克服这一点，我们首先通过利用两个关键假设来自动为教学视频语料库生成伪摘要：（i）相关步骤可能会出现在相同任务（任务相关性）的多个视频中，并且（ii）它们更重要。可能由示威者口头描述（跨模式显着）。我们提出了一个教学视频摘要网络，该网络结合了上下文感知的时间视频编码器和段评分变压器。使用伪摘要作为弱监督，我们的网络为仅给出视频和转录语音的教学视频构建了视觉摘要。为了评估我们的模型，我们通过刮擦包含视频演示的Wikihow文章和步骤的视觉描绘，从而收集了高质量的测试集，即Wikihow摘要，从而使我们能够获得地面真实性摘要。我们的表现优于几个基线和这个新基准的最先进的视频摘要模型。

Visual and audio modalities are highly correlated, yet they contain different information. Their strong correlation makes it possible to predict the semantics of one from the other with good accuracy. Their intrinsic differences make cross-modal prediction a potentially more rewarding pretext task for self-supervised learning of video and audio representations compared to within-modality learning. Based on this intuition, we propose Cross-Modal Deep Clustering (XDC), a novel selfsupervised method that leverages unsupervised clustering in one modality (e.g., audio) as a supervisory signal for the other modality (e.g., video). This cross-modal supervision helps XDC utilize the semantic correlation and the differences between the two modalities. Our experiments show that XDC outperforms single-modality clustering and other multi-modal variants. XDC achieves state-of-the-art accuracy among self-supervised methods on multiple video and audio benchmarks. Most importantly, our video model pretrained on large-scale unlabeled data significantly outperforms the same model pretrained with full-supervision on ImageNet and Kinetics for action recognition on HMDB51 and UCF101. To the best of our knowledge, XDC is the first self-supervised learning method that outperforms large-scale fully-supervised pretraining for action recognition on the same architecture.

最近的动作识别模型通过整合对象，其位置和互动来取得令人印象深刻的结果。但是，为每个框架获得密集的结构化注释是乏味且耗时的，使这些方法的训练昂贵且可扩展性较低。同时，如果可以在感兴趣的域内或之外使用一小部分带注释的图像，我们如何将它们用于下游任务的视频？我们提出了一个学习框架的结构（简称SVIT），该结构证明了仅在训练过程中仅可用的少量图像的结构才能改善视频模型。 SVIT依靠两个关键见解。首先，由于图像和视频都包含结构化信息，因此我们用一组\ emph {对象令牌}丰富了一个可以在图像和视频中使用的\ emph {对象令牌}的模型。其次，视频中各个帧的场景表示应与静止图像的场景表示“对齐”。这是通过\ emph {frame-clip一致性}损失来实现的，该损失可确保图像和视频之间结构化信息的流动。我们探索场景结构的特定实例化，即\ emph {手对象图}，由手和对象组成，其位置为节点，以及触点/no-contact的物理关系作为边缘。 SVIT在多个视频理解任务和数据集上显示出强烈的性能改进；它在EGO4D CVPR'22对象状态本地化挑战中赢得了第一名。对于代码和预算模型，请访问\ url {https://eladb3.github.io/svit/}的项目页面

对于人类的行动理解，流行的研究方向是分析具有明确的语义含量的短视频剪辑，例如跳跃和饮酒。然而，了解短语行动的方法不能直接翻译成长期以来的人类动态，如跳舞，即使在语义上也是挑战的挑战。同时，自然语言处理（NLP）社区通过大规模预培训解决了稀缺的类似挑战，这改善了一种模型的几个下游任务。在这项工作中，我们研究如何以自我监督的方式进行分段和群集视频，即Acton Discovery，朝向视频标记的主要障碍。我们提出了一种两级框架，首先通过对应于它们的时间上下文的视频帧的两个增强视图对比其次的视频帧的两个增强视图来获得帧智表示。然后通过k-means群集视频集集中的帧展表示。然后通过从同一簇内的帧形成连续的运动序列来自动提取actons。通过标准化的相互信息和语言熵，我们通过Kendall的Tau和Lexicon构建步骤进行评估框架明智的表现。我们还研究了这个标记化的三种应用：类型分类，行动细分和行动组成。在AIST ++和PKU-MMD数据集上，与几个基线相比，Actons带来了显着的性能改进。

我们研究了联合视频和语言（VL）预培训，以实现跨模型学习和益处丰富的下游VL任务。现有的作品要么提取低质量的视频特征或学习有限的文本嵌入，但忽略了高分辨率视频和多样化的语义可以显着提高跨模型学习。在本文中，我们提出了一种新的高分辨率和多样化的视频 - 语言预训练模型（HD-VILA），用于许多可视任务。特别是，我们收集具有两个不同属性的大型数据集：1）第一个高分辨率数据集包括371.5k小时的720p视频，2）最多样化的数据集涵盖15个流行的YouTube类别。为了启用VL预培训，我们通过学习丰富的时空特征的混合变压器联合优化HD-VILA模型，以及多峰变压器，用于强制学习视频功能与多样化文本的交互。我们的预训练模式实现了新的最先进的导致10 VL了解任务和2个新颖的文本到视觉生成任务。例如，我们以零拍摄MSR-VTT文本到视频检索任务的相对增加38.5％R @ 1的相对增长，高分辨率数据集LSMDC为53.6％。学习的VL嵌入也有效地在文本到视觉操纵和超分辨率任务中产生视觉上令人愉悦和语义相关结果。

我们提出了MACLR，这是一种新颖的方法，可显式执行从视觉和运动方式中学习的跨模式自我监督的视频表示。与以前的视频表示学习方法相比，主要关注学习运动线索的研究方法是隐含的RGB输入，MACLR丰富了RGB视频片段的标准对比度学习目标，具有运动途径和视觉途径之间的跨模式学习目标。我们表明，使用我们的MACLR方法学到的表示形式更多地关注前景运动区域，因此可以更好地推广到下游任务。为了证明这一点，我们在五个数据集上评估了MACLR，以进行动作识别和动作检测，并在所有数据集上展示最先进的自我监督性能。此外，我们表明MACLR表示可以像在UCF101和HMDB51行动识别的全面监督下所学的表示一样有效，甚至超过了对Vidsitu和SSV2的行动识别的监督表示，以及对AVA的动作检测。

The remarkable success of deep learning in various domains relies on the availability of large-scale annotated datasets. However, obtaining annotations is expensive and requires great effort, which is especially challenging for videos. Moreover, the use of human-generated annotations leads to models with biased learning and poor domain generalization and robustness. As an alternative, self-supervised learning provides a way for representation learning which does not require annotations and has shown promise in both image and video domains. Different from the image domain, learning video representations are more challenging due to the temporal dimension, bringing in motion and other environmental dynamics. This also provides opportunities for video-exclusive ideas that advance self-supervised learning in the video and multimodal domain. In this survey, we provide a review of existing approaches on self-supervised learning focusing on the video domain. We summarize these methods into four different categories based on their learning objectives: 1) pretext tasks, 2) generative learning, 3) contrastive learning, and 4) cross-modal agreement. We further introduce the commonly used datasets, downstream evaluation tasks, insights into the limitations of existing works, and the potential future directions in this area.

时间动作细分任务段视频暂时，并预测所有帧的动作标签。充分监督这种细分模型需要密集的框架动作注释，这些注释既昂贵又乏味。这项工作是第一个提出一个组成动作发现（CAD）框架的工作，该框架仅需要视频高级复杂活动标签作为时间动作分割的监督。提出的方法会自动使用活动分类任务发现组成视频动作。具体而言，我们定义了有限数量的潜在作用原型来构建视频级别的双重表示，通过活动分类培训共同学习了这些原型。这种设置赋予我们的方法，可以在多个复杂活动中发现潜在的共享动作。由于缺乏行动水平的监督，我们采用匈牙利匹配算法将潜在的动作原型与地面真理语义类别进行评估联系起来。我们表明，通过高级监督，匈牙利的匹配可以从现有的视频和活动级别扩展到全球水平。全球级别的匹配允许跨活动进行行动共享，这在文献中从未考虑过。广泛的实验表明，我们发现的动作可以帮助执行时间动作细分和活动识别任务。

Video recognition in an open and dynamic world is quite challenging, as we need to handle different settings such as close-set, long-tail, few-shot and open-set. By leveraging semantic knowledge from noisy text descriptions crawled from the Internet, we focus on the general video recognition (GVR) problem of solving different recognition tasks within a unified framework. The core contribution of this paper is twofold. First, we build a comprehensive video recognition benchmark of Kinetics-GVR, including four sub-task datasets to cover the mentioned settings. To facilitate the research of GVR, we propose to utilize external textual knowledge from the Internet and provide multi-source text descriptions for all action classes. Second, inspired by the flexibility of language representation, we present a unified visual-linguistic framework (VLG) to solve the problem of GVR by an effective two-stage training paradigm. Our VLG is first pre-trained on video and language datasets to learn a shared feature space, and then devises a flexible bi-modal attention head to collaborate high-level semantic concepts under different settings. Extensive results show that our VLG obtains the state-of-the-art performance under four settings. The superior performance demonstrates the effectiveness and generalization ability of our proposed framework. We hope our work makes a step towards the general video recognition and could serve as a baseline for future research. The code and models will be available at https://github.com/MCG-NJU/VLG.

了解多媒体内容中描述或显示的事件彼此相关是开发可用于真实世界媒体的强大人工智能系统的关键组成部分。尽管许多研究专门用于文本，图像和视频域中的事件理解，但没有一个研究探索事件跨域中经历的复杂关系。例如，新闻文章可能会描述“抗议”事件，而视频显示“逮捕”事件。认识到视觉“逮捕”事件是更广泛的“抗议”事件的一个子事件，这是一个具有挑战性但重要的问题，但前面的工作尚未探讨。在本文中，我们提出了多模式事件关系关系的新任务，以识别这种跨模式事件关系。我们贡献了一个大规模数据集，该数据集由100K视频新文章对组成，以及密集注释的数据的基准。我们还提出了一种弱监督的多模式方法，该方法将来自外部知识库（KB）的常识性知识整合在一起，以预测丰富的多模式事件层次结构。实验表明，我们的模型在我们提出的基准上优于许多竞争基线。我们还对模型的性能进行了详细的分析，并建议未来研究的方向。

我们介绍了空间本地化叙述中的视频中的任务。我们的方法的关键是能够学会在与随附的叙述的视频中的大型视频中对自我监督进行空间地定位与自我监督的互动。为实现这一目标，我们提出了一种多层跨模型关注网络，可以在培训期间有效优化对比损失。我们介绍了一种分割的策略，可以通过视觉和自然语言方式计算和中间模态注意力之间的交替，这允许通过直接对比两种方式的表示来实现有效的培训。我们展示了我们对HOWTO100M教学数据集的自我训练的方法的有效性，并在YouCook2 DataSet中的本地化描述交互的新收集数据集上进行评估。我们展示了我们的方法优于替代基准，包括浅薄的共同关注和完全跨越的关注。我们还将我们的方法应用于在Flickr30k上的弱监管下的图像中的接地短语，并显示堆叠多个注意层是有效的，并且当与对区域丢失相结合时，在召回召回和指向时达到最先进的艺术状态手准确性。

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。

There is a natural correlation between the visual and auditive elements of a video. In this work we leverage this connection to learn general and effective models for both audio and video analysis from self-supervised temporal synchronization. We demonstrate that a calibrated curriculum learning scheme, a careful choice of negative examples, and the use of a contrastive loss are critical ingredients to obtain powerful multi-sensory representations from models optimized to discern temporal synchronization of audio-video pairs. Without further finetuning, the resulting audio features achieve performance superior or comparable to the state-of-the-art on established audio classification benchmarks (DCASE2014 and ESC-50). At the same time, our visual subnet provides a very effective initialization to improve the accuracy of video-based action recognition models: compared to learning from scratch, our self-supervised pretraining yields a remarkable gain of +19.9% in action recognition accuracy on UCF101 and a boost of +17.7% on HMDB51.