Image-text multimodal representation learning aligns data across modalities and enables important medical applications, e.g., image classification, visual grounding, and cross-modal retrieval. In this work, we establish a connection between multimodal representation learning and multiple instance learning. Based on this connection, we propose a generic framework for constructing permutation-invariant score functions with many existing multimodal representation learning approaches as special cases. Furthermore, we use the framework to derive a novel contrastive learning approach and demonstrate that our method achieves state-of-the-art results on a number of downstream tasks.
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生物医学中的多模式数据遍布,例如放射学图像和报告。大规模解释这些数据对于改善临床护理和加速临床研究至关重要。与一般领域相比,具有复杂语义的生物医学文本在视觉建模中提出了其他挑战,并且先前的工作使用了缺乏特定领域语言理解的适应性模型不足。在本文中,我们表明,有原则的文本语义建模可以大大改善自我监督的视力 - 语言处理中的对比度学习。我们发布了一种实现最先进的语言模型,从而通过改进的词汇和新颖的语言预测客观的客观利用语义和话语特征在放射学报告中获得了自然语言推断。此外,我们提出了一种自我监督的联合视觉 - 语言方法,重点是更好的文本建模。它在广泛的公开基准上建立了新的最新结果,部分是通过利用我们新的特定领域的语言模型。我们释放了一个新的数据集,该数据集具有放射科医生的局部对齐短语接地注释,以促进生物医学视觉处理中复杂语义建模的研究。广泛的评估,包括在此新数据集中,表明我们的对比学习方法在文本语义建模的帮助下,尽管仅使用了全球对准目标,但在细分任务中的表现都优于细分任务中的先验方法。
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学习医学图像的视觉表示(例如X射线)是医学图像理解的核心,但由于人类注释的稀缺性,其进步已经阻止了它。现有的工作通常依赖于从成像网预处理传输的微调权重,由于图像特征截然不同,这是次优的,或者是从文本报告数据与医学图像配对的基于规则的标签提取,这是不准确的,难以推广。同时,最近的几项研究表明,从自然图像中学习的对比度学习令人兴奋,但由于它们的高层间相似性,我们发现这些方法对医学图像无济于事。我们提出了Concirt,这是一种替代的无监督策略,通过利用自然存在的配对描述性文本来学习医学视觉表示。我们通过两种模式之间的双向对比度目标对医学图像进行预处理编码的新方法是域,无关,不需要其他专家输入。我们通过将预处理的权重转移到4个医学图像分类任务和2个零射击检索任务中来测试交通,并证明它导致图像表示,在大多数设置中,它们都超过了强大的基线。值得注意的是,在所有4个分类任务中,我们的方法仅需要10 \%标记的培训数据与成像网初始化的对应物,以实现更好或可比的性能,从而证明了卓越的数据效率。
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已经证明对比学习有效地对未标记数据的预训练图像模型有效,并且有希望的医学图像分类等任务的结果。在预训练期间使用配对文本和图像(例如放射性报告和图像)甚至进一步改善了结果。尽管如此,大多数现有方法将图像分类为下游任务,并且对于像语义分割或物体检测等本地化任务可能不是最佳的。因此,我们提出了从愿景和文本(Lovt)的局部代表学习,以实现我们最佳知识,这是针对本地化医学成像任务的第一种文本监督的预训练方法。我们的方法将实例级图像报告对比学习与图像区域和报告句子表示的局部对比学习结合起来。我们评估LOVT和常用的预培训方法,这些评估框架是由五个公共数据集的胸部X光上的18个本地化任务组成的新评估框架。虽然没有单一的最佳方法,但是,在18个研究的任务中,Lovt在11个中最佳地表现出优选的选择本地化任务的首选方法。
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作为人类已知的最直观的界面之一,自然语言有可能调解许多涉及人类计算机互动的任务,尤其是在音乐信息检索等以应用程序为中心的领域。在这项工作中,我们探索了跨模式学习,以试图在音乐领域弥合音频和语言。为此,我们提出了Muscall,这是音乐对比的音频学习框架。我们的方法由双重编码架构组成,该体系结构了解音乐音频和描述性句子对之间的对齐方式,生成可用于文本到原告和音频到文本检索的多模式嵌入。多亏了这个属性,肌肉几乎可以转移到任何可以作为基于文本检索的任务转移到任何任务。我们的实验表明,我们的方法在检索音频时的性能要比基线要好得多,该音频与文本描述匹配,相反,与音频查询匹配的文本。我们还证明,我们的模型的多模式对齐能力可以成功扩展到零摄像转移方案,用于流派分类和在两个公共数据集上自动标记。
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Deep neural networks have been successfully adopted to diverse domains including pathology classification based on medical images. However, large-scale and high-quality data to train powerful neural networks are rare in the medical domain as the labeling must be done by qualified experts. Researchers recently tackled this problem with some success by taking advantage of models pre-trained on large-scale general domain data. Specifically, researchers took contrastive image-text encoders (e.g., CLIP) and fine-tuned it with chest X-ray images and paired reports to perform zero-shot pathology classification, thus completely removing the need for pathology-annotated images to train a classification model. Existing studies, however, fine-tuned the pre-trained model with the same contrastive learning objective, and failed to exploit the multi-labeled nature of medical image-report pairs. In this paper, we propose a new fine-tuning strategy based on sentence sampling and positive-pair loss relaxation for improving the downstream zero-shot pathology classification performance, which can be applied to any pre-trained contrastive image-text encoders. Our method consistently showed dramatically improved zero-shot pathology classification performance on four different chest X-ray datasets and 3 different pre-trained models (5.77% average AUROC increase). In particular, fine-tuning CLIP with our method showed much comparable or marginally outperformed to board-certified radiologists (0.619 vs 0.625 in F1 score and 0.530 vs 0.544 in MCC) in zero-shot classification of five prominent diseases from the CheXpert dataset.
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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。
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从纯图像和具有对比性损失的纯图像和文本预测的自我监督的视觉语言是有效的,但是由于双流式体系结构仅在全球层面上与图像和文本表示形式对齐,因此忽略了细粒度​​的对齐。早些时候,受监督的,非对比度的方法具有更细粒度的对齐方式,但需要致密的注释,这些注释不可伸缩。我们提出了一个单个流体系结构,该体系结构使用两个新颖的任务:对称交叉模式重建(XMM)和一个伪标记的关键字预测,将图像和语言对齐:全局,细粒度的补丁和概念/语义(PSL)。在XMM中,我们从一种模态掩盖了输入令牌,并使用跨模式信息重建掩盖的令牌,从而改善了两种模式之间的细粒度对齐。在PSL中,我们使用注意力在标题中选择关键字,使用动量编码器推荐标题中缺少但在图像中表示的其他重要关键字,然后训练视觉编码器以预测这些关键字的存在,并帮助它。学习对于将文本令牌接地到图像区域至关重要的语义概念。我们证明了对图像文本检索,接地,视觉问题的回答/推理的竞争性能和提高的数据效率,以针对对更多数据进行培训的较大模型和模型。 Zaidkhan.me/simla上可用的代码和型号。
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Large-scale vision and language representation learning has shown promising improvements on various vision-language tasks. Most existing methods employ a transformer-based multimodal encoder to jointly model visual tokens (region-based image features) and word tokens. Because the visual tokens and word tokens are unaligned, it is challenging for the multimodal encoder to learn image-text interactions. In this paper, we introduce a contrastive loss to ALign the image and text representations BEfore Fusing (ALBEF) them through cross-modal attention, which enables more grounded vision and language representation learning. Unlike most existing methods, our method does not require bounding box annotations nor high-resolution images. To improve learning from noisy web data, we propose momentum distillation, a self-training method which learns from pseudo-targets produced by a momentum model. We provide a theoretical analysis of ALBEF from a mutual information maximization perspective, showing that different training tasks can be interpreted as different ways to generate views for an image-text pair. ALBEF achieves state-of-the-art performance on multiple downstream visionlanguage tasks. On image-text retrieval, ALBEF outperforms methods that are pre-trained on orders of magnitude larger datasets. On VQA and NLVR 2 , ALBEF achieves absolute improvements of 2.37% and 3.84% compared to the state-ofthe-art, while enjoying faster inference speed. Code and models are available at https://github.com/salesforce/ALBEF.
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Pre-trained representations are becoming crucial for many NLP and perception tasks. While representation learning in NLP has transitioned to training on raw text without human annotations, visual and vision-language representations still rely heavily on curated training datasets that are expensive or require expert knowledge. For vision applications, representations are mostly learned using datasets with explicit class labels such as Ima-geNet or OpenImages. For vision-language, popular datasets like Conceptual Captions, MSCOCO, or CLIP all involve a non-trivial data collection (and cleaning) process. This costly curation process limits the size of datasets and hence hinders the scaling of trained models. In this paper, we leverage a noisy dataset of over one billion image alt-text pairs, obtained without expensive filtering or post-processing steps in the Conceptual Captions dataset. A simple dual-encoder architecture learns to align visual and language representations of the image and text pairs using a contrastive loss. We show that the scale of our corpus can make up for its noise and leads to state-of-the-art representations even with such a simple learning scheme. Our visual representation achieves strong performance when transferred to classification tasks such as ImageNet and VTAB. The aligned visual and language representations enables zero-shot image classification and also set new state-of-the-art results on Flickr30K and MSCOCO image-text retrieval benchmarks, even when compared with more sophisticated crossattention models. The representations also enable cross-modality search with complex text and text + image queries.
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Vision语言中最现有的方法依赖于通过对象检测提取的对象中心特征,并在提取的功能和文本之间进行细粒度对齐。我们认为物体检测的使用可能不适合视觉语言预培训。相反,我们指出应该执行任务,以便文本中提到的“视觉概念”的区域位于图像中,并且在文本和视觉概念之间的平时对齐中,识别在其中的校准处于多个 - 粒度。本文提出了一种称为X-VLM的新方法,以执行“多粒度的视觉语言预训练”。实验结果表明,X-VLM在许多下游视觉语言任务中始终如一地优于最先进的方法。
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我们在这项研究中的目标是研究一个更现实的环境,在这种环境中,我们可以为细粒度的产品类别进行弱监督的多模式实例级产品检索。我们首先贡献了product1m数据集,并定义了两个实际实例级检索任务,以实现价格比较和个性化建议的评估。对于两个实例级任务,如何准确地指出视觉语言数据中提到的产品目标并有效地降低了无关紧要的内容的影响非常具有挑战性。为了解决这个问题,我们利用训练一个更有效的跨模式与模型,该模型能够自适应地能够通过使用一个实体图,其节点和边缘分别表示实体和相似性,从而可以从多模式数据中合并来自多模式数据的关键概念信息。实体。具体而言,为实例级别的商品检索提出了一种新型的实体图增强的跨模式预处理(EGE-CMP)模型,该模型明确地将基于节点的基于节点的基于节点和子图的方式显式地注入实体知识。自我监管的混合流变压器可以减少不同对象内容之间的混淆,从而有效地指导网络专注于具有真实语义的实体。实验结果很好地验证了我们的EGE-CMP的功效和概括性,表现优于几个SOTA跨模式基线,例如夹子,Uniter和Capture。
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最先进的愿景和愿景和语言模型依靠大规模的Visio-linguisting预借鉴,以获得各种下游任务的良好性能。通常,这种模型通常是跨模态(对比)或多模态(具有早期融合)但不是两者;它们通常只针对特定的方式或任务。有希望的方向将是使用单一整体普遍模型,作为“基础”,目标是一次性的所有方式 - 真正的视觉和语言基础模型应该擅长视力任务,语言任务和交叉和多数模态视觉和语言任务。我们将Flava介绍在这样的模型中,并在跨越这些目标模式的广泛的35个任务上展示令人印象深刻的性能。
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视觉预训练的最新进展表明,在不同的视觉任务中表现出惊人的表现,阐明了对人工智能研究中对视觉和文本概念的全面理解的长期问题。但是,在医学领域的视觉预训练的应用方面取得了有限数量和多样性阻碍了对联合视觉语言概念的成功学习。在这项研究中,我们介绍了Max-VL,这是一种针对医疗领域中有效视觉预训练的模型。我们在实验上证明,预先训练的MAX-VL模型在各种视觉任务中都优于当前最新视觉语言模型。我们还提出了用于诊断新出现疾病和人为错误检测的临床实用性,并显示了该模型在不同领域数据中的广泛适用性。
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Learning fine-grained interplay between vision and language allows to a more accurate understanding for VisionLanguage tasks. However, it remains challenging to extract key image regions according to the texts for semantic alignments. Most existing works are either limited by textagnostic and redundant regions obtained with the frozen detectors, or failing to scale further due to its heavy reliance on scarce grounding (gold) data to pre-train detectors. To solve these problems, we propose Self-Locator Aided Network (SLAN) for cross-modal understanding tasks without any extra gold data. SLAN consists of a region filter and a region adaptor to localize regions of interest conditioned on different texts. By aggregating cross-modal information, the region filter selects key regions and the region adaptor updates their coordinates with text guidance. With detailed region-word alignments, SLAN can be easily generalized to many downstream tasks. It achieves fairly competitive results on five cross-modal understanding tasks (e.g., 85.7% and 69.2% on COCO image-to-text and text-to-image retrieval, surpassing previous SOTA methods). SLAN also demonstrates strong zero-shot and fine-tuned transferability to two localization tasks.
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In the field of cross-modal retrieval, single encoder models tend to perform better than dual encoder models, but they suffer from high latency and low throughput. In this paper, we present a dual encoder model called BagFormer that utilizes a cross modal interaction mechanism to improve recall performance without sacrificing latency and throughput. BagFormer achieves this through the use of bag-wise interactions, which allow for the transformation of text to a more appropriate granularity and the incorporation of entity knowledge into the model. Our experiments demonstrate that BagFormer is able to achieve results comparable to state-of-the-art single encoder models in cross-modal retrieval tasks, while also offering efficient training and inference with 20.72 times lower latency and 25.74 times higher throughput.
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以前的视觉语言预训练模型主要构建具有令牌和对象(像素)的多模式输入,然后在它们之间执行交叉模式相互作用。我们认为,只有令牌和对象的输入限制了诸如短语到区域接地之类的高级语义对齐。同时,多层次对齐本质上是一致的,并且能够协同促进表示形式学习。因此,在本文中,我们建议学习视觉预训练(MVPTR)的多级语义一致性。在MVPTR中,我们遵循两种方式的嵌套结构,以引入概念为高级语义。为了简化从多模式多级输入的学习,我们的框架分为两个阶段,第一阶段着重于模式内多级表示学习,第二阶段通过粗粒和细粒度跨模态强化了跨模式的交互语义对齐任务。除了常用的图像文本匹配和掩盖语言模型任务外,我们还引入了第一阶段蒙版概念恢复任务以增强概念表示学习,第二阶段的另外两个任务在第二阶段中,以明确鼓励跨跨层次的多层次对准方式。我们的代码可在https://github.com/junction4nako/mvp_pytorch上找到。
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大规模的视觉预训练在各种下游任务中都表现出了令人印象深刻的进步。现有方法主要是通过图像和文本的全局表示形式的相似性或对图像和文本特征上的高级交叉模式关注来对跨模式对齐进行建模。但是,由于只有全局图像文本对齐信息,因此他们无法明确学习视觉区域和文本短语之间的细粒语义对齐。在本文中,我们介绍了Loupe,这是一种精细的语义一致性视觉语言预训练框架,该框架从新颖的游戏理论互动的角度学习了细粒度的语义对齐。为了有效地计算游戏理论相互作用,我们进一步提出了一种不确定性感知的神经Shapley交互学习模块。实验表明,Loupe在图像文本检索基准测试中实现了最新的。如果没有任何对象级的人类注释和微调,Loupe就可以在对象检测和视觉接地方面实现竞争性能。更重要的是,Loupe从大规模的原始图像文本对学习细粒语义的新方向。
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我们提出了Clip-Lite,一种通过与文本注释的特征对齐方式进行视觉表示学习的信息有效方法。与先前提出的剪辑模型相比,剪辑液在优化其对比学学习目标期间只需要一个负图像文本样本对。我们通过利用信息有效的较低限制来实现这一点,以最大化两个输入模态之间的相互信息。这允许剪辑Lite培训,在获得比夹子的更好的性能的同时具有显着减少的数据和批量尺寸。我们通过在Coco-Tablions数据集上预先绘制来评估剪贴画并对其他数据集进行测试传输。 Clip-Lite在Pascal VOC分类上获得+ 15.4%的映射绝对增益,并在ImageNet上获得A + 22.1%的前1个精度增益,同时与其他更复杂,文本监督模型相当或优越。 Clip-Lite还优于剪辑图像和文本检索,零拍分类和视觉接地。最后,通过在表示学习期间执行显式图像文本对齐,我们显示Clip-Lite可以利用语言语义来鼓励可以在下游任务中使用的无偏见的视觉表示。
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Multimodal models are becoming increasingly effective, in part due to unified components, such as the Transformer architecture. However, multimodal models still often consist of many task- and modality-specific pieces and training procedures. For example, CLIP (Radford et al., 2021) trains independent text and image towers via a contrastive loss. We explore an additional unification: the use of a pure pixel-based model to perform image, text, and multimodal tasks. Our model is trained with contrastive loss alone, so we call it CLIP-Pixels Only (CLIPPO). CLIPPO uses a single encoder that processes both regular images and text rendered as images. CLIPPO performs image-based tasks such as retrieval and zero-shot image classification almost as well as CLIP, with half the number of parameters and no text-specific tower or embedding. When trained jointly via image-text contrastive learning and next-sentence contrastive learning, CLIPPO can perform well on natural language understanding tasks, without any word-level loss (language modelling or masked language modelling), outperforming pixel-based prior work. Surprisingly, CLIPPO can obtain good accuracy in visual question answering, simply by rendering the question and image together. Finally, we exploit the fact that CLIPPO does not require a tokenizer to show that it can achieve strong performance on multilingual multimodal retrieval without
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