这份技术报告描述了我们对2022年SOCCERNET挑战的行动提交。挑战是CVPR 2022 ActivityNet研讨会的一部分。我们的提交是基于我们最近提出的一种方法，该方法的重点是通过一组密集采样的检测锚来提高时间精度。由于其对时间精度的重视，这种方法能够在使用较小的时间评估公差的严格平均地图度量上产生竞争结果。最近提出的指标是用于挑战的评估标准。为了进一步改善结果，我们在这里引入了预处理和后处理步骤的小变化，并通过晚期融合结合不同的输入特征类型。本报告描述了由此产生的总体方法，重点是引入的修改。我们还描述了所使用的培训程序，并提出了我们的结果。

我们提出了一个用于视频中时间精确的动作发现的模型，该模型使用一组密集的检测锚，预测了每个锚的检测置信度和相应的细粒时间位移。我们尝试两个行李箱体系结构，两者都能够合并大的时间上下文，同时保留精确本地化所需的较小规模的功能：U-NET的一维版本和变压器编码器（TE）。我们还建议通过应用清晰度最小化（SAM）和混合数据扩展来提出这种培训模型的最佳实践。我们在Soccernet-V2上实现了新的最新技术，这是同类的最大足球视频数据集，其时间定位明显改善。此外，我们的消融表明：预测时间位移的重要性；U-Net和TE Trunks之间的权衡；以及与SAM和MIDUP培训的好处。

我们介绍了在视频中发现时间精确，细粒度事件的任务（检测到时间事件的精确时刻）。精确的斑点需要模型在全球范围内对全日制动作规模进行推理，并在本地识别微妙的框架外观和运动差异，以识别这些动作过程中事件的识别。令人惊讶的是，我们发现，最高的绩效解决方案可用于先前的视频理解任务，例如操作检测和细分，不能同时满足这两个要求。作为响应，我们提出了E2E点，这是一种紧凑的端到端模型，在精确的发现任务上表现良好，可以在单个GPU上快速培训。我们证明，E2E点的表现明显优于最近根据视频动作检测，细分和将文献发现到精确的发现任务的基线。最后，我们为几个细粒度的运动动作数据集贡献了新的注释和分裂，以使这些数据集适用于未来的精确发现工作。

Temporal action detection (TAD) is extensively studied in the video understanding community by generally following the object detection pipeline in images. However, complex designs are not uncommon in TAD, such as two-stream feature extraction, multi-stage training, complex temporal modeling, and global context fusion. In this paper, we do not aim to introduce any novel technique for TAD. Instead, we study a simple, straightforward, yet must-known baseline given the current status of complex design and low detection efficiency in TAD. In our simple baseline (termed BasicTAD), we decompose the TAD pipeline into several essential components: data sampling, backbone design, neck construction, and detection head. We extensively investigate the existing techniques in each component for this baseline, and more importantly, perform end-to-end training over the entire pipeline thanks to the simplicity of design. As a result, this simple BasicTAD yields an astounding and real-time RGB-Only baseline very close to the state-of-the-art methods with two-stream inputs. In addition, we further improve the BasicTAD by preserving more temporal and spatial information in network representation (termed as PlusTAD). Empirical results demonstrate that our PlusTAD is very efficient and significantly outperforms the previous methods on the datasets of THUMOS14 and FineAction. Meanwhile, we also perform in-depth visualization and error analysis on our proposed method and try to provide more insights on the TAD problem. Our approach can serve as a strong baseline for future TAD research. The code and model will be released at https://github.com/MCG-NJU/BasicTAD.

We address temporal action localization in untrimmed long videos. This is important because videos in real applications are usually unconstrained and contain multiple action instances plus video content of background scenes or other activities. To address this challenging issue, we exploit the effectiveness of deep networks in temporal action localization via three segment-based 3D ConvNets: (1) a proposal network identifies candidate segments in a long video that may contain actions; (2) a classification network learns one-vs-all action classification model to serve as initialization for the localization network; and (3) a localization network fine-tunes the learned classification network to localize each action instance. We propose a novel loss function for the localization network to explicitly consider temporal overlap and achieve high temporal localization accuracy. In the end, only the proposal network and the localization network are used during prediction. On two largescale benchmarks, our approach achieves significantly superior performances compared with other state-of-the-art systems: mAP increases from 1.7% to 7.4% on MEXaction2 and increases from 15.0% to 19.0% on THUMOS 2014.

基于自我注意力的变压器模型已显示出令人印象深刻的图像分类和对象检测结果，并且最近用于视频理解。受此成功的启发，我们研究了变压器网络在视频中的时间动作本地化的应用。为此，我们提出了ActionFormer，这是一个简单而强大的模型，可在不使用动作建议或依靠预定义的锚点窗口中识别其及时识别其类别并识别其类别。 ActionFormer将多尺度特征表示与局部自我发作相结合，并使用轻加权解码器对每个时刻进行分类并估算相应的动作边界。我们表明，这种精心策划的设计会在先前的工作中进行重大改进。如果没有铃铛和口哨声，ActionFormer在Thumos14上的TIOU = 0.5的地图达到了71.0％的地图，表现优于最佳先前模型的绝对百分比14.1。此外，ActionFormer在ActivityNet 1.3（平均地图36.6％）和Epic-Kitchens 100（+先前工作的平均地图+13.5％）上显示出很强的结果。我们的代码可从http://github.com/happyharrycn/actionformer_release获得。

Humans perceive the world by concurrently processing and fusing high-dimensional inputs from multiple modalities such as vision and audio. Machine perception models, in stark contrast, are typically modality-specific and optimised for unimodal benchmarks, and hence late-stage fusion of final representations or predictions from each modality (`late-fusion') is still a dominant paradigm for multimodal video classification. Instead, we introduce a novel transformer based architecture that uses `fusion bottlenecks' for modality fusion at multiple layers. Compared to traditional pairwise self-attention, our model forces information between different modalities to pass through a small number of bottleneck latents, requiring the model to collate and condense the most relevant information in each modality and only share what is necessary. We find that such a strategy improves fusion performance, at the same time reducing computational cost. We conduct thorough ablation studies, and achieve state-of-the-art results on multiple audio-visual classification benchmarks including Audioset, Epic-Kitchens and VGGSound. All code and models will be released.

To understand the world, we humans constantly need to relate the present to the past, and put events in context. In this paper, we enable existing video models to do the same. We propose a long-term feature bank-supportive information extracted over the entire span of a video-to augment state-of-the-art video models that otherwise would only view short clips of 2-5 seconds. Our experiments demonstrate that augmenting 3D convolutional networks with a long-term feature bank yields state-of-the-art results on three challenging video datasets: AVA, EPIC-Kitchens, and Charades. Code is available online. 1 1 https://github.com/facebookresearch/ video-long-term-feature-banks Input clip (4 seconds) Target frame

时间动作检测（TAD）旨在确定未修剪视频中每个动作实例的语义标签和边界。先前的方法通过复杂的管道来解决此任务。在本文中，我们提出了一个具有简单集的预测管道的端到端时间动作检测变压器（TADTR）。给定一组名为“动作查询”的可学习嵌入，Tadtr可以从每个查询的视频中自适应提取时间上下文，并直接预测动作实例。为了适应TAD的变压器，我们提出了三个改进，以提高其所在地意识。核心是一个时间可变形的注意模块，在视频中有选择地参加一组稀疏的密钥片段。片段的完善机制和动作回归头旨在完善预测实例的边界和信心。 TADTR需要比以前的检测器更低的计算成本，同时保留了出色的性能。作为一个独立的检测器，它在Thumos14（56.7％地图）和HACS段（32.09％地图）上实现了最先进的性能。结合一个额外的动作分类器，它在ActivityNet-1.3上获得了36.75％的地图。我们的代码可在\ url {https://github.com/xlliu7/tadtr}上获得。

表示像素位移的光流量广泛用于许多计算机视觉任务中以提供像素级运动信息。然而，随着卷积神经网络的显着进展，建议最近的最先进的方法直接在特征级别解决问题。由于特征向量的位移不与像素位移不一致，因此常用方法是：将光流向神经网络向前传递到任务数据集上的微调该网络。利用这种方法，他们期望微调网络来产生编码特征级运动信息的张量。在本文中，我们重新思考此事实上的范式并分析了视频对象检测任务中的缺点。为了缓解这些问题，我们提出了一种具有视频对象检测的\ textBF {i} n-network \ textbf {f} eature \ textbf {f} eature \ textbf {f}低估计模块（iff模块）的新型网络（iff-net）。在不借鉴任何其他数据集的预先训练，我们的IFF模块能够直接产生\ textBF {feature flow}，表示特征位移。我们的IFF模块由一个浅模块组成，它与检测分支共享该功能。这种紧凑的设计使我们的IFF-Net能够准确地检测对象，同时保持快速推断速度。此外，我们提出了基于\ Textit {自我监督}的转换剩余损失（TRL），这进一步提高了IFF-Net的性能。我们的IFF-Net优于现有方法，并在Imagenet VID上设置最先进的性能。

使用多模式输入的对象检测可以改善许多安全性系统，例如自动驾驶汽车（AVS）。由白天和黑夜运行的AV动机，我们使用RGB和热摄像机研究多模式对象检测，因为后者在较差的照明下提供了更强的对象签名。我们探索融合来自不同方式的信息的策略。我们的关键贡献是一种概率结合技术，Proben，一种简单的非学习方法，可以将多模式的检测融合在一起。我们从贝叶斯的规则和第一原则中得出了探针，这些原则在跨模态上采用条件独立性。通过概率边缘化，当检测器不向同一物体发射时，概率可以优雅地处理缺失的方式。重要的是，即使有条件的独立性假设不存在，也可以显着改善多模式检测，例如，从其他融合方法（包括现成的内部和训练有素的内部）融合输出。我们在两个基准上验证了包含对齐（KAIST）和未对准（Flir）多模式图像的基准，这表明Proben的相对性能优于先前的工作超过13％！

Context-aware decision support in the operating room can foster surgical safety and efficiency by leveraging real-time feedback from surgical workflow analysis. Most existing works recognize surgical activities at a coarse-grained level, such as phases, steps or events, leaving out fine-grained interaction details about the surgical activity; yet those are needed for more helpful AI assistance in the operating room. Recognizing surgical actions as triplets of <instrument, verb, target> combination delivers comprehensive details about the activities taking place in surgical videos. This paper presents CholecTriplet2021: an endoscopic vision challenge organized at MICCAI 2021 for the recognition of surgical action triplets in laparoscopic videos. The challenge granted private access to the large-scale CholecT50 dataset, which is annotated with action triplet information. In this paper, we present the challenge setup and assessment of the state-of-the-art deep learning methods proposed by the participants during the challenge. A total of 4 baseline methods from the challenge organizers and 19 new deep learning algorithms by competing teams are presented to recognize surgical action triplets directly from surgical videos, achieving mean average precision (mAP) ranging from 4.2% to 38.1%. This study also analyzes the significance of the results obtained by the presented approaches, performs a thorough methodological comparison between them, in-depth result analysis, and proposes a novel ensemble method for enhanced recognition. Our analysis shows that surgical workflow analysis is not yet solved, and also highlights interesting directions for future research on fine-grained surgical activity recognition which is of utmost importance for the development of AI in surgery.

最近的方法表明，直接在大规模图像文本对集合上训练深神网络可以在各种识别任务上进行零拍传输。一个中心问题是如何将其推广到对象检测，这涉及本地化的非语义任务以及分类的语义任务。为了解决这个问题，我们引入了一种视觉嵌入对准方法，该方法将审计模型（例如夹子）（例如夹子）的概括能力传输到像Yolov5这样的对象检测器。我们制定了一个损耗函数，使我们能够将图像和文本嵌入在预审计的模型夹中对齐与检测器的修改语义预测头。通过这种方法，我们能够训练一个对象检测器，该对象检测器可以在可可，ILSVRC和视觉基因组零摄像机检测基准上实现最先进的性能。在推断期间，我们的模型可以适应以检测任何数量的对象类，而无需其他培训。我们还发现，标准对象检测缩放可以很好地传输到我们的方法，并在Yolov5模型和Yolov3模型的各种尺度上找到一致的改进。最后，我们开发了一种自我标记的方法，该方法可提供显着的分数改进，而无需额外的图像或标签。

对人类对象相互作用的理解在第一人称愿景（FPV）中至关重要。遵循相机佩戴者操纵的对象的视觉跟踪算法可以提供有效的信息，以有效地建模此类相互作用。在过去的几年中，计算机视觉社区已大大提高了各种目标对象和场景的跟踪算法的性能。尽管以前有几次尝试在FPV域中利用跟踪器，但仍缺少对最先进跟踪器的性能的有条理分析。这项研究差距提出了一个问题，即应使用当前的解决方案``现成''还是应进行更多特定领域的研究。本文旨在为此类问题提供答案。我们介绍了FPV中单个对象跟踪的首次系统研究。我们的研究广泛分析了42个算法的性能，包括通用对象跟踪器和基线FPV特定跟踪器。分析是通过关注FPV设置的不同方面，引入新的绩效指标以及与FPV特定任务有关的。这项研究是通过引入Trek-150（由150个密集注释的视频序列组成的新型基准数据集）来实现的。我们的结果表明，FPV中的对象跟踪对当前的视觉跟踪器构成了新的挑战。我们强调了导致这种行为的因素，并指出了可能的研究方向。尽管遇到了困难，但我们证明了跟踪器为需要短期对象跟踪的FPV下游任务带来好处。我们预计，随着新的和FPV特定的方法学会得到研究，通用对象跟踪将在FPV中受欢迎。

The 1$^{\text{st}}$ Workshop on Maritime Computer Vision (MaCVi) 2023 focused on maritime computer vision for Unmanned Aerial Vehicles (UAV) and Unmanned Surface Vehicle (USV), and organized several subchallenges in this domain: (i) UAV-based Maritime Object Detection, (ii) UAV-based Maritime Object Tracking, (iii) USV-based Maritime Obstacle Segmentation and (iv) USV-based Maritime Obstacle Detection. The subchallenges were based on the SeaDronesSee and MODS benchmarks. This report summarizes the main findings of the individual subchallenges and introduces a new benchmark, called SeaDronesSee Object Detection v2, which extends the previous benchmark by including more classes and footage. We provide statistical and qualitative analyses, and assess trends in the best-performing methodologies of over 130 submissions. The methods are summarized in the appendix. The datasets, evaluation code and the leaderboard are publicly available at https://seadronessee.cs.uni-tuebingen.de/macvi.

转移学习是用于训练小型目标数据集深层网络的主要范式。通常在大型``上游''数据集上预估计用于分类的模型，因为此类标签易于收集，然后在``下游''任务（例如动作本地化）上进行了填充，这些任务由于其较细粒度的注释而较小。在本文中，我们质疑这种方法，并提出共同访问 - 同时在多个``上游''和``下游''任务上训练单个模型。我们证明，在使用相同的数据总量时，共同传统的表现优于传统的转移学习，并且还展示了我们如何轻松地将方法扩展到多个``上游''数据集以进一步提高性能。尤其是，共同访问可以显着提高我们下游任务中稀有类别的性能，因为它具有正规化的效果，并使网络能够学习在不同数据集之间传输的功能表示。最后，我们观察到如何与公共，视频分类数据集共同进行，我们能够在挑战性的AVA和AVA-Kinetics数据集上实现最新的时空动作的结果，超过了最新的作品，这些作品的最新作品会发展出复杂的作品楷模。

To balance the annotation labor and the granularity of supervision, single-frame annotation has been introduced in temporal action localization. It provides a rough temporal location for an action but implicitly overstates the supervision from the annotated-frame during training, leading to the confusion between actions and backgrounds, i.e., action incompleteness and background false positives. To tackle the two challenges, in this work, we present the Snippet Classification model and the Dilation-Erosion module. In the Dilation-Erosion module, we expand the potential action segments with a loose criterion to alleviate the problem of action incompleteness and then remove the background from the potential action segments to alleviate the problem of action incompleteness. Relying on the single-frame annotation and the output of the snippet classification, the Dilation-Erosion module mines pseudo snippet-level ground-truth, hard backgrounds and evident backgrounds, which in turn further trains the Snippet Classification model. It forms a cyclic dependency. Furthermore, we propose a new embedding loss to aggregate the features of action instances with the same label and separate the features of actions from backgrounds. Experiments on THUMOS14 and ActivityNet 1.2 validate the effectiveness of the proposed method. Code has been made publicly available (https://github.com/LingJun123/single-frame-TAL).

当前的时空动作管检测方法通常将一个给定键框的边界框提案扩展到附近帧的3D颞轴和池特征。但是，如果演员的位置或形状通过大型的2D运动和可变性，由于大型摄像机运动，大型演员形状变形，快速演员的动作等，这种合并就无法积累有意义的时空特征。在这项工作中，我们旨在研究在大动作下的动作检测中观察到Cuboid感知特征聚集的性能。此外，我们建议通过跟踪参与者并沿各个轨道进行时间特征聚集来增强演员特征表示。我们在各种固定时间尺度的动作管/轨道框之间使用相交的行动者（IOU）定义了演员运动。随着时间的推移，具有较大运动的动作将导致较低的IOU，并且较慢的动作将保持更高的IOU。我们发现，轨道感知功能聚集始终取得了巨大的改善，尤其是对于与Cuboid感知的基线相比，在大型运动下进行的动作。结果，我们还报告了大规模多运动数据集的最先进。

Detecting actions in untrimmed videos should not be limited to a small, closed set of classes. We present a simple, yet effective strategy for open-vocabulary temporal action detection utilizing pretrained image-text co-embeddings. Despite being trained on static images rather than videos, we show that image-text co-embeddings enable openvocabulary performance competitive with fully-supervised models. We show that the performance can be further improved by ensembling the image-text features with features encoding local motion, like optical flow based features, or other modalities, like audio. In addition, we propose a more reasonable open-vocabulary evaluation setting for the ActivityNet data set, where the category splits are based on similarity rather than random assignment.

在诸如人类姿态估计的关键点估计任务中，尽管具有显着缺点，但基于热线的回归是主要的方法：Heatmaps本质上遭受量化误差，并且需要过多的计算来产生和后处理。有动力寻找更有效的解决方案，我们提出了一种新的热映射无关声点估计方法，其中各个关键点和空间相关的关键点（即，姿势）被建模为基于密集的单级锚的检测框架内的对象。因此，我们将我们的方法Kapao（发音为“KA-Pow！”）对于关键点并作为对象构成。我们通过同时检测人姿势对象和关键点对象并融合检测来利用两个对象表示的强度来将Kapao应用于单阶段多人人类姿势估算问题。在实验中，我们观察到Kapao明显比以前的方法更快，更准确，这极大地来自热爱处理后处理。此外，在不使用测试时间增强时，精度速度折衷特别有利。我们的大型型号Kapao-L在Microsoft Coco Keypoints验证集上实现了70.6的AP，而无需测试时增强，其比下一个最佳单级模型更准确，4.0 AP更准确。此外，Kapao在重闭塞的存在下擅长。在繁荣试验套上，Kapao-L为一个单级方法实现新的最先进的准确性，AP为68.9。