这项工作是在培训生成动作/视频识别模型上,其输出是描述视频的自由形式的特定动作标题(而不是动作类标签)。生成的方法具有实用的优势,例如生产更细粒度和人类可读的产出,并且自然而然地是开放的。为此,我们提议适应视频/动作识别的预先训练的生成视觉和语言(V&L)基础模型。据我们所知,最近有几次尝试适应了用对比度学习(例如剪辑)训练的V&L模型(例如剪辑),但据我们所知,我们提出了第一种设定实现这一目标的方法来实现生成模型的方法。我们首先表明,生成模型的直接微调生产具有严重过度拟合的动作类别。为了减轻这一点,我们介绍了REST,这是一个由两个关键组成部分组成的培训框架:一种无监督的方法,用于通过伪捕获生成和自我训练,将生成模型适应动作/视频,即不使用任何动作特定的标签; (b)基于剪辑的检索方法,用于为每个视频发现一套伪装的伪扣,以训练该模型。重要的是,我们表明这两个组件对于获得高精度都是必要的。我们评估零拍动识别的问题的休息,我们表明,与基于对比的学习方法相比,我们的方法非常有竞争力。代码将可用。
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探索大规模预处理的基础模型对计算机视觉具有重大兴趣,因为这些模型可以快速转移到许多下游任务中。本文介绍了对比字幕(COCA),这是一种极简主义的设计,旨在为图像文本编码器编码器基础模型预算与对比度损失和字幕损失,从而从剪辑和诸如simvlm之类的生成方法之类的对比方法中包含模型能力。与所有解码器层都参与编码器输出的标准编码器 - 模块变压器相反,可口可乐省略了解码器层的上半部分的交叉注意,以编码单峰文本表示,并串联到剩余的解码器层,这些解码器与图像编码器相交的解码器层多模式图像文本表示。除了对多模态解码器输出的字幕损失外,我们还应用了单峰图像和文本嵌入之间的对比损失,该输出可以预测文本令牌自动加压。通过共享相同的计算图,可以用最小的开销有效地计算两个培训目标。可口可乐是端到端和从头开始的网络尺度alt-text数据和带注释的图像,通过将所有标签视为文本,无缝地统一自然语言监督以进行表示。从经验上讲,可口可乐通过零拍传输或在广泛的下游任务上进行零摄像转移或最少的特定任务适应,跨越视觉识别(Imagenet,Kinetics-400/600/700,瞬间, ),交叉模式检索(MSCOCO,FLICKR30K,MSR-VTT),多模式理解(VQA,SNLI-VE,NLVR2)和图像字幕(MSCOCO,NOCAPS)。值得注意的是,在Imagenet分类方面,COCA获得了86.3%的TOP-1准确性,带有冷冻编码器和学习的分类头90.6%,以及带有填充编码器的Imagenet上的新最先进的91.0%Top-1 Top-1精度。
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This work explores an efficient approach to establish a foundational video-text model for tasks including open-vocabulary video classification, text-to-video retrieval, video captioning and video question-answering. We present VideoCoCa that reuses a pretrained image-text contrastive captioner (CoCa) model and adapt it to video-text tasks with minimal extra training. While previous works adapt image-text models with various cross-frame fusion modules (for example, cross-frame attention layer or perceiver resampler) and finetune the modified architecture on video-text data, we surprisingly find that the generative attentional pooling and contrastive attentional pooling layers in the image-text CoCa design are instantly adaptable to ``flattened frame embeddings'', yielding a strong zero-shot transfer baseline for many video-text tasks. Specifically, the frozen image encoder of a pretrained image-text CoCa takes each video frame as inputs and generates \(N\) token embeddings per frame for totally \(T\) video frames. We flatten \(N \times T\) token embeddings as a long sequence of frozen video representation and apply CoCa's generative attentional pooling and contrastive attentional pooling on top. All model weights including pooling layers are directly loaded from an image-text CoCa pretrained model. Without any video or video-text data, VideoCoCa's zero-shot transfer baseline already achieves state-of-the-art results on zero-shot video classification on Kinetics 400/600/700, UCF101, HMDB51, and Charades, as well as zero-shot text-to-video retrieval on MSR-VTT and ActivityNet Captions. We also explore lightweight finetuning on top of VideoCoCa, and achieve strong results on video question-answering (iVQA, MSRVTT-QA, MSVD-QA) and video captioning (MSR-VTT, ActivityNet, Youcook2). Our approach establishes a simple and effective video-text baseline for future research.
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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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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.
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我们介绍了一种零拍的视频字幕方法,该方法采用了两个冷冻网络:GPT-2语言模型和剪辑图像文本匹配模型。匹配分数用于引导语言模型生成一个句子,该句子的平均匹配分数高于视频帧的一个子集。与零拍图像字幕方法不同,我们的工作立即考虑整个句子。这是通过在生成过程中优化从头开始的一部分,通过在提示中修改所有其他令牌的表示,并通过迭代重复该过程,逐渐提高生成句子的特殊性和全面性来实现。我们的实验表明,生成的字幕是连贯的,并显示了广泛的现实知识。我们的代码可在以下网址找到:https://github.com/yoadtew/zero-shot-video-to-text
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Large-scale multi-modal training with image-text pairs imparts strong generalization to CLIP model. Since training on a similar scale for videos is infeasible, recent approaches focus on the effective transfer of image-based CLIP to the video domain. In this pursuit, new parametric modules are added to learn temporal information and inter-frame relationships which require meticulous design efforts. Furthermore, when the resulting models are learned on videos, they tend to overfit on the given task distribution and lack in generalization aspect. This begs the following question: How to effectively transfer image-level CLIP representations to videos? In this work, we show that a simple Video Fine-tuned CLIP (ViFi-CLIP) baseline is generally sufficient to bridge the domain gap from images to videos. Our qualitative analysis illustrates that the frame-level processing from CLIP image-encoder followed by feature pooling and similarity matching with corresponding text embeddings helps in implicitly modeling the temporal cues within ViFi-CLIP. Such fine-tuning helps the model to focus on scene dynamics, moving objects and inter-object relationships. For low-data regimes where full fine-tuning is not viable, we propose a `bridge and prompt' approach that first uses fine-tuning to bridge the domain gap and then learns prompts on language and vision side to adapt CLIP representations. We extensively evaluate this simple yet strong baseline on zero-shot, base-to-novel generalization, few-shot and fully supervised settings across five video benchmarks. Our code is available at https://github.com/muzairkhattak/ViFi-CLIP.
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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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The foundation models have recently shown excellent performance on a variety of downstream tasks in computer vision. However, most existing vision foundation models simply focus on image-level pretraining and adpation, which are limited for dynamic and complex video-level understanding tasks. To fill the gap, we present general video foundation models, InternVideo, by taking advantage of both generative and discriminative self-supervised video learning. Specifically, InternVideo efficiently explores masked video modeling and video-language contrastive learning as the pretraining objectives, and selectively coordinates video representations of these two complementary frameworks in a learnable manner to boost various video applications. Without bells and whistles, InternVideo achieves state-of-the-art performance on 39 video datasets from extensive tasks including video action recognition/detection, video-language alignment, and open-world video applications. Especially, our methods can obtain 91.1% and 77.2% top-1 accuracy on the challenging Kinetics-400 and Something-Something V2 benchmarks, respectively. All of these results effectively show the generality of our InternVideo for video understanding. The code will be released at https://github.com/OpenGVLab/InternVideo .
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视频问题回答(VideoQA)是一项复杂的任务,需要多种模式数据进行培训。但是,对视频的问题和答案的手动注释是乏味的,禁止可扩展性。为了解决这个问题,最近的方法考虑了零拍设置,而无需手动注释视觉问题。特别是,一种有前途的方法调整了在网络级文本数据中预测的冻结自回归语言模型,以适应多模式输入。相比之下,我们在这里建立在冷冻双向语言模型(BILM)的基础上,并表明这种方法为零拍出的VideoQA提供了更强大,更便宜的替代方案。特别是(i)我们使用轻型训练模块将视觉输入与冷冻的BILM结合在一起,(ii)我们使用Web-Scrafe Multi-Mododal数据训练此类模块,最后(iii)我们通过掩盖语言执行零声录像带推断建模,其中蒙版文本是给定问题的答案。我们提出的方法Frozenbilm在零摄影的视频中的表现优于最高的,包括LSMDC-FIB,包括LSMDC-FIB,IVQA,MSRVTT-QA,MSVD-QA,ActivityNet-QA,TGIF-FRAMEQA,TGIF-FRAMEQA,,TGIF-FRAMEQA,,TGIF-FRAMEQA,,,MSRVTT-QA,MSRVTT-QA,MSRVTT-QA,MSRVTT-QA,MSRVTT-QA,,均优于最新技术。 How2QA和TVQA。它还在几次且完全监督的环境中展示了竞争性能。我们的代码和模型将在https://antoyang.github.io/frozenbilm.html上公开提供。
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使用自然语言作为培训视觉识别模型的监督持有巨大的承诺。最近的作品表明,如果在大型训练数据集中的图像和标题之间的对齐形式使用此类监督,则结果对齐模型在零拍摄分类中表现出色,如下游任务2。在本文中,我们专注于挑逗语言监督的哪些部分对于训练零拍摄图像分类模型至关重要。通过广泛和仔细的实验​​,我们表明:1)可以将简单的单词(弓)标题用作数据集中大多数图像标题的替代品。令人惊讶的是,我们观察到这种方法在与单词平衡结合时提高了零拍分类性能。 2)使用船首净化模型,我们可以通过在没有标题的图像上生成伪弓标题来获得更多培训数据。使用真实和伪弓形标题培训的模型达到了更强的零射性能。在ImageNet-1K零拍评估中,我们只使用3M图像标题对的最佳模型,使用15M图像标题对培训的剪辑模型(31.5%VS 31.3%)进行剪辑。
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本文介绍了Omnivl,这是一种新的基础模型,旨在使用一种通用体系结构来支持图像语言和视频语言任务。它为图像和视频输入采用了统一的基于变压器的视觉编码器,因此可以执行联合图像语言和视频语言预处理。我们首次证明了这样的范式受益于图像和视频任务,而不是传统的单向传输(例如,使用图像语言来帮助视频语言)。为此,我们提出了对图像语言和视频语言的脱钩关节预处理,以有效地将视觉模型分解为空间和时间维度,并在图像和视频任务上获得性能提升。此外,我们引入了一种新颖的统一视觉对比度(UNIVLC)损失,以利用图像文本,视频文本,图像标签(例如,图像分类),视频标签(例如,视频动作识别)在一起受到监督和吵闹的监督预处理数据都尽可能多地利用。无需额外的任务适配器,Omnivl可以同时支持仅视觉任务(例如,图像分类,视频操作识别),跨模式对齐任务(例如,图像/视频 - 文本检索)和多模式理解和生成任务(例如,图像/视频问答,字幕)。我们在各种下游任务上评估Omnivl,并以相似的模型大小和数据量表获得最新的或竞争结果。
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Most existing text-video retrieval methods focus on cross-modal matching between the visual content of offline videos and textual query sentences. However, in real scenarios, online videos are frequently accompanied by relevant text information such as titles, tags, and even subtitles, which can be utilized to match textual queries. This inspires us to generate associated captions from offline videos to help with existing text-video retrieval methods. To do so, we propose to use the zero-shot video captioner with knowledge of pre-trained web-scale models (e.g., CLIP and GPT-2) to generate captions for offline videos without any training. Given the captions, one question naturally arises: what can auxiliary captions do for text-video retrieval? In this paper, we present a novel framework Cap4Video, which makes use of captions from three aspects: i) Input data: The video and captions can form new video-caption pairs as data augmentation for training. ii) Feature interaction: We perform feature interaction between video and caption to yield enhanced video representations. iii) Output score: The Query-Caption matching branch can be complementary to the original Query-Video matching branch for text-video retrieval. We conduct thorough ablation studies to demonstrate the effectiveness of our method. Without any post-processing, our Cap4Video achieves state-of-the-art performance on MSR-VTT (51.4%), VATEX (66.6%), MSVD (51.8%), and DiDeMo (52.0%).
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视觉语言预培训对从大规模Web数据学习联合视觉文本表示的巨大成功,展示了零拍广泛的显着能力。本文介绍了一种简单的方法,可以将一个预先训练的视觉语言模型有效地调整到具有最小培训的新型任务,以及这里,我们考虑视频了解任务。具体而言,我们建议优化几个随机向量,称为连续提示向量,将新颖任务转换为与预培训目标相同的格式。此外,为了弥合静态图像和视频之间的差距,用堆叠在框架明智的视觉特征之上的轻量压变压器编码时分信息。在实验上,我们进行广泛的消融研究,以分析关键组成部分和必需品。在9个公共基准的行动认可,行动本地化和文本 - 视频检索,跨封闭式,几次射击,开放式场景,我们为现有方法实现了竞争或最先进的性能,尽管培训显着更少的参数。
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可以代表和描述环境声音的机器具有实际潜力,例如,用于音频标记和标题系统。普遍的学习范式已经依赖于并行音频文本数据,但是,Web上几乎没有可用。我们提出了vip-ant,它在不使用任何并行音频文本数据的情况下诱导\ textbf {a} udio- \ textBF {t} EXT对齐。我们的主要思想是在双模形图像文本表示和双模态图像 - 音频表示之间共享图像模型;图像模态用作枢轴,并将音频和文本连接在三模态嵌入空间中。在没有配对的音频文本数据的困难零拍设置中,我们的模型在ESC50和US8K音频分类任务上展示了最先进的零点性能,甚至超过了披肩标题的领域的监督状态检索(带音频查询)2.2 \%R @ 1。我们进一步调查了最小音频监控的情况,发现,例如,只有几百个监督的音频文本对将零拍音频分类精度提高8 \%US8K。然而,为了匹配人类奇偶校验,我们的经验缩放实验表明我们需要大约2米$ 2 ^ {21} \约2M $监督的音频标题对。我们的工作开辟了新的途径,用于学习音频文本连接,几乎没有并行音频文本数据。
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培训有效的视频和语言模型直观地需要多个帧作为模型输入。但是,目前尚不清楚使用多个帧是否有利于下游任务,如果是的话,性能增益是否值得通过使用更多帧产生的巨大计算和内存成本。在这项工作中,我们探索了视频和语言学习的单帧模型。在各种视频和语言任务(包括文本到视频检索和视频问题)上,我们显示出令人惊讶的结果,即通过大规模的预训练和适当的框架合奏在推理时,与使用多个训练的现有方法相比,不考虑时间信息的单帧训练模型可以实现更好的性能。该结果揭示了流行的视频和语言数据集中存在强烈的“静态外观偏差”。因此,为了对视频和语言模型进行更全面的评估,我们建议基于现有的细粒度识别数据集,提出了两个新的检索任务,以鼓励时间建模。我们的代码可从https://github.com/jayleicn/singularity获得
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Large-scale cross-modal pre-training paradigms have recently shown ubiquitous success on a wide range of downstream tasks, e.g., zero-shot classification, retrieval and image captioning. However, their successes highly rely on the scale and quality of web-crawled data that naturally contain incomplete and noisy information (e.g., wrong or irrelevant content). Existing works either design manual rules to clean data or generate pseudo-targets as auxiliary signals for reducing noise impact, which do not explicitly tackle both the incorrect and incomplete challenges simultaneously. In this paper, to automatically mitigate the impact of noise by solely mining over existing data, we propose a principled Noise-robust Language-Image Pre-training framework (NLIP) to stabilize pre-training via two schemes: noise-harmonization and noise-completion. First, in noise-harmonization scheme, NLIP estimates the noise probability of each pair according to the memorization effect of cross-modal transformers, then adopts noise-adaptive regularization to harmonize the cross-modal alignments with varying degrees. Second, in noise-completion scheme, to enrich the missing object information of text, NLIP injects a concept-conditioned cross-modal decoder to obtain semantic-consistent synthetic captions to complete noisy ones, which uses the retrieved visual concepts (i.e., objects' names) for the corresponding image to guide captioning generation. By collaboratively optimizing noise-harmonization and noise-completion schemes, our NLIP can alleviate the common noise effects during image-text pre-training in a more efficient way. Extensive experiments show the significant performance improvements of our NLIP using only 26M data over existing pre-trained models (e.g., CLIP, FILIP and BLIP) on 12 zero-shot classification datasets, MSCOCO image captioning and zero-shot image-text retrieval tasks.
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我们引入了构图软提示(CSP),这是一种参数有效的学习技术,可改善大规模预处理视觉模型(VLMS)的零摄像组成性。 VLM可以在其灵活的文本编码器中代表任意类作为自然语言提示,但在组成零击基准任务上的表现不佳。为了改善VLM,我们提出了一种新颖的软提示形式。我们将构成的属性和对象视为将类定义为词汇的可学习令牌,并在多个及时的构图上调整它们。在推断期间,我们在新组合中重新组装了学习的属性对象词汇。我们表明,CSP在基准数据集上的原始VLM的表现平均为AUC上的10.9个百分点。 CSP还胜过Coop,这是一种调谐前缀上下文的软提示方法,在AUC上平均要点5.8个百分点。我们执行其他实验,以表明CSP对仅属性分类,高阶属性 - 属性对象组成以及预验证属性和微调对象的组合进行了改进。
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Prompt tuning is a new few-shot transfer learning technique that only tunes the learnable prompt for pre-trained vision and language models such as CLIP. However, existing prompt tuning methods tend to learn spurious or entangled representations, which leads to poor generalization to unseen concepts. Towards non-spurious and efficient prompt learning from limited examples, this paper presents a novel \underline{\textbf{C}}ounterfactual \underline{\textbf{P}}rompt \underline{\textbf{L}}earning (CPL) method for vision and language models, which simultaneously employs counterfactual generation and contrastive learning in a joint optimization framework. Particularly, CPL constructs counterfactual by identifying minimal non-spurious feature change between semantically-similar positive and negative samples that causes concept change, and learns more generalizable prompt representation from both factual and counterfactual examples via contrastive learning. Extensive experiments demonstrate that CPL can obtain superior few-shot performance on different vision and language tasks than previous prompt tuning methods on CLIP. On image classification, we achieve 3.55\% average relative improvement on unseen classes across seven datasets; on image-text retrieval and visual question answering, we gain up to 4.09\% and 25.08\% relative improvements across three few-shot scenarios on unseen test sets respectively.
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State-of-the-art computer vision systems are trained to predict a fixed set of predetermined object categories. This restricted form of supervision limits their generality and usability since additional labeled data is needed to specify any other visual concept. Learning directly from raw text about images is a promising alternative which leverages a much broader source of supervision. We demonstrate that the simple pre-training task of predicting which caption goes with which image is an efficient and scalable way to learn SOTA image representations from scratch on a dataset of 400 million (image, text) pairs collected from the internet. After pre-training, natural language is used to reference learned visual concepts (or describe new ones) enabling zero-shot transfer of the model to downstream tasks. We study the performance of this approach by benchmarking on over 30 different existing computer vision datasets, spanning tasks such as OCR, action recognition in videos, geo-localization, and many types of fine-grained object classification. The model transfers non-trivially to most tasks and is often competitive with a fully supervised baseline without the need for any dataset specific training. For instance, we match the accuracy of the original ResNet-50 on ImageNet zero-shot without needing to use any of the 1.28 million training examples it was trained on. We release our code and pre-trained model weights at https://github.com/OpenAI/CLIP.
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