Accurate whole-body multi-person pose estimation and tracking is an important yet challenging topic in computer vision. To capture the subtle actions of humans for complex behavior analysis, whole-body pose estimation including the face, body, hand and foot is essential over conventional body-only pose estimation. In this paper, we present AlphaPose, a system that can perform accurate whole-body pose estimation and tracking jointly while running in realtime. To this end, we propose several new techniques: Symmetric Integral Keypoint Regression (SIKR) for fast and fine localization, Parametric Pose Non-Maximum-Suppression (P-NMS) for eliminating redundant human detections and Pose Aware Identity Embedding for jointly pose estimation and tracking. During training, we resort to Part-Guided Proposal Generator (PGPG) and multi-domain knowledge distillation to further improve the accuracy. Our method is able to localize whole-body keypoints accurately and tracks humans simultaneously given inaccurate bounding boxes and redundant detections. We show a significant improvement over current state-of-the-art methods in both speed and accuracy on COCO-wholebody, COCO, PoseTrack, and our proposed Halpe-FullBody pose estimation dataset. Our model, source codes and dataset are made publicly available at https://github.com/MVIG-SJTU/AlphaPose.

Multi-person pose estimation in the wild is challenging. Although state-of-the-art human detectors have demonstrated good performance, small errors in localization and recognition are inevitable. These errors can cause failures for a single-person pose estimator (SPPE), especially for methods that solely depend on human detection results. In this paper, we propose a novel regional multi-person pose estimation (RMPE) framework to facilitate pose estimation in the presence of inaccurate human bounding boxes. Our framework consists of three components: Symmetric Spatial Transformer Network (SSTN), Parametric Pose Non-Maximum-Suppression (NMS), and Pose-Guided Proposals Generator (PGPG). Our method is able to handle inaccurate bounding boxes and redundant detections, allowing it to achieve 76.7 mAP on the MPII (multi person) dataset [3]. Our model and source codes are made publicly available. † . * part of this work was done when Hao-Shu Fang was an student intern in Tencent § corresponding author is Cewu Lu † https://cvsjtu.wordpress.com/rmpe-regional-multi-person-pose-estimation/

本文调查了2D全身人类姿势估计的任务，该任务旨在将整个人体（包括身体，脚，脸部和手）局部定位在整个人体上。我们提出了一种称为Zoomnet的单网络方法，以考虑到完整人体的层次结构，并解决不同身体部位的规模变化。我们进一步提出了一个称为Zoomnas的神经体系结构搜索框架，以促进全身姿势估计的准确性和效率。Zoomnas共同搜索模型体系结构和不同子模块之间的连接，并自动为搜索的子模块分配计算复杂性。为了训练和评估Zoomnas，我们介绍了第一个大型2D人类全身数据集，即可可叶全体V1.0，它注释了133个用于野外图像的关键点。广泛的实验证明了Zoomnas的有效性和可可叶v1.0的重要性。

The topic of multi-person pose estimation has been largely improved recently, especially with the development of convolutional neural network. However, there still exist a lot of challenging cases, such as occluded keypoints, invisible keypoints and complex background, which cannot be well addressed. In this paper, we present a novel network structure called Cascaded Pyramid Network (CPN) which targets to relieve the problem from these "hard" keypoints. More specifically, our algorithm includes two stages: Glob-alNet and RefineNet. GlobalNet is a feature pyramid network which can successfully localize the "simple" keypoints like eyes and hands but may fail to precisely recognize the occluded or invisible keypoints. Our RefineNet tries explicitly handling the "hard" keypoints by integrating all levels of feature representations from the Global-Net together with an online hard keypoint mining loss. In general, to address the multi-person pose estimation problem, a top-down pipeline is adopted to first generate a set of human bounding boxes based on a detector, followed by our CPN for keypoint localization in each human bounding box. Based on the proposed algorithm, we achieve stateof-art results on the COCO keypoint benchmark, with average precision at 73.0 on the COCO test-dev dataset and 72.1 on the COCO test-challenge dataset, which is a 19% relative improvement compared with 60.5 from the COCO 2016 keypoint challenge. Code 1 and the detection results are publicly available for further research.

我们提出了一种直接的，基于回归的方法，以从单个图像中估计2D人姿势。我们将问题提出为序列预测任务，我们使用变压器网络解决了问题。该网络直接学习了从图像到关键点坐标的回归映射，而无需诉诸中间表示（例如热图）。这种方法避免了与基于热图的方法相关的许多复杂性。为了克服以前基于回归的方法的特征错位问题，我们提出了一种注意机制，该机制适应与目标关键最相关的功能，从而大大提高了准确性。重要的是，我们的框架是端到端的可区分，并且自然学会利用关键点之间的依赖关系。两个主要的姿势估计数据集在MS-Coco和MPII上进行的实验表明，我们的方法在基于回归的姿势估计中的最新方法显着改善。更值得注意的是，与最佳的基于热图的姿势估计方法相比，我们的第一种基于回归的方法是有利的。

There has been significant progress on pose estimation and increasing interests on pose tracking in recent years. At the same time, the overall algorithm and system complexity increases as well, making the algorithm analysis and comparison more difficult. This work provides simple and effective baseline methods. They are helpful for inspiring and evaluating new ideas for the field. State-of-the-art results are achieved on challenging benchmarks. The code will be available at https://github. com/leoxiaobin/pose.pytorch.

Realtime multi-person 2D pose estimation is a key component in enabling machines to have an understanding of people in images and videos. In this work, we present a realtime approach to detect the 2D pose of multiple people in an image. The proposed method uses a nonparametric representation, which we refer to as Part Affinity Fields (PAFs), to learn to associate body parts with individuals in the image. This bottom-up system achieves high accuracy and realtime performance, regardless of the number of people in the image. In previous work, PAFs and body part location estimation were refined simultaneously across training stages. We demonstrate that a PAF-only refinement rather than both PAF and body part location refinement results in a substantial increase in both runtime performance and accuracy. We also present the first combined body and foot keypoint detector, based on an internal annotated foot dataset that we have publicly released. We show that the combined detector not only reduces the inference time compared to running them sequentially, but also maintains the accuracy of each component individually. This work has culminated in the release of OpenPose, the first open-source realtime system for multi-person 2D pose detection, including body, foot, hand, and facial keypoints.

在本文中，我们考虑了同时找到和从单个2D图像中恢复多手的具有挑战性的任务。先前的研究要么关注单手重建，要么以多阶段的方式解决此问题。此外，常规的两阶段管道首先检测到手部区域，然后估计每个裁剪贴片的3D手姿势。为了减少预处理和特征提取中的计算冗余，我们提出了一条简洁但有效的单阶段管道。具体而言，我们为多手重建设计了多头自动编码器结构，每个HEAD网络分别共享相同的功能图并分别输出手动中心，姿势和纹理。此外，我们采用了一个弱监督的计划来减轻昂贵的3D现实世界数据注释的负担。为此，我们提出了一系列通过舞台训练方案优化的损失，其中根据公开可用的单手数据集生成具有2D注释的多手数据集。为了进一步提高弱监督模型的准确性，我们在单手和多个手设置中采用了几个功能一致性约束。具体而言，从本地功能估算的每只手的关键点应与全局功能预测的重新投影点一致。在包括Freihand，HO3D，Interhand 2.6M和RHD在内的公共基准测试的广泛实验表明，我们的方法在弱监督和完全监督的举止中优于基于最先进的模型方法。代码和模型可在{\ url {https://github.com/zijinxuxu/smhr}}上获得。

人类的姿势估计旨在弄清不同场景中所有人的关键。尽管结果有希望，但目前的方法仍然面临一些挑战。现有的自上而下的方法单独处理一个人，而没有不同的人与所在的场景之间的相互作用。因此，当发生严重闭塞时，人类检测的表现会降低。另一方面，现有的自下而上方法同时考虑所有人，并捕获整个图像的全局知识。但是，由于尺度变化，它们的准确性不如自上而下的方法。为了解决这些问题，我们通过整合自上而下和自下而上的管道来探索不同接受场的视觉线索并实现其互补性，提出了一种新颖的双皮线整合变压器（DPIT）。具体而言，DPIT由两个分支组成，自下而上的分支介绍了整个图像以捕获全局视觉信息，而自上而下的分支则从单人类边界框中提取本地视觉的特征表示。然后，从自下而上和自上而下的分支中提取的特征表示形式被馈入变压器编码器，以交互融合全局和本地知识。此外，我们定义了关键点查询，以探索全景和单人类姿势视觉线索，以实现两个管道的相互互补性。据我们所知，这是将自下而上和自上而下管道与变压器与人类姿势估计的变压器相结合的最早作品之一。关于可可和MPII数据集的广泛实验表明，我们的DPIT与最先进的方法相当。

In this paper, we are interested in the human pose estimation problem with a focus on learning reliable highresolution representations. Most existing methods recover high-resolution representations from low-resolution representations produced by a high-to-low resolution network. Instead, our proposed network maintains high-resolution representations through the whole process.We start from a high-resolution subnetwork as the first stage, gradually add high-to-low resolution subnetworks one by one to form more stages, and connect the mutliresolution subnetworks in parallel. We conduct repeated multi-scale fusions such that each of the high-to-low resolution representations receives information from other parallel representations over and over, leading to rich highresolution representations. As a result, the predicted keypoint heatmap is potentially more accurate and spatially more precise. We empirically demonstrate the effectiveness of our network through the superior pose estimation results over two benchmark datasets: the COCO keypoint detection dataset and the MPII Human Pose dataset. In addition, we show the superiority of our network in pose tracking on the PoseTrack dataset. The code and models have been publicly available at https://github.com/leoxiaobin/ deep-high-resolution-net.pytorch.

Bottom-up human pose estimation methods have difficulties in predicting the correct pose for small persons due to challenges in scale variation. In this paper, we present HigherHRNet: a novel bottom-up human pose estimation method for learning scale-aware representations using high-resolution feature pyramids. Equipped with multi-resolution supervision for training and multiresolution aggregation for inference, the proposed approach is able to solve the scale variation challenge in bottom-up multi-person pose estimation and localize keypoints more precisely, especially for small person. The feature pyramid in HigherHRNet consists of feature map outputs from HRNet and upsampled higher-resolution outputs through a transposed convolution. HigherHR-Net outperforms the previous best bottom-up method by 2.5% AP for medium person on COCO test-dev, showing its effectiveness in handling scale variation. Furthermore, HigherHRNet achieves new state-of-the-art result on COCO test-dev (70.5% AP) without using refinement or other post-processing techniques, surpassing all existing bottom-up methods. HigherHRNet even surpasses all topdown methods on CrowdPose test (67.6% AP), suggesting its robustness in crowded scene. The code and models are available at https://github.com/HRNet/ Higher-HRNet-Human-Pose-Estimation.

在多人2D姿势估计中，自下而上的方法同时预测了所有人的姿势，与自上而下的方法不同，不依赖于人类的检测。但是，与现有的自上而下方法相比，SOTA自下而上的方法的精度仍然不如较低。这是由于预测的人类姿势是根据不一致的人类边界箱中心进行回归的，并且缺乏人类规范的正常化，从而导致预测的人类姿势被遗漏了不准确和小规模的人。为了推动自下而上的姿势估计的信封，我们首先提出了多尺度训练，以增强网络以通过单尺度测试来处理规模变化，尤其是对于小规模的人。其次，我们介绍了双解剖中心（即头部和身体），在这里我们可以更准确，可靠地预测人类的姿势，尤其是对于小规模的人。此外，现有的自下而上方法采用多尺度测试来以多个额外的前向通行证的价格提高姿势估计的准确性，这削弱了自下而上方法的效率，与自上而下的方法相比，核心强度。相比之下，我们的多尺度训练使该模型能够预测单个前向通行证（即单尺度测试）中的高质量姿势。我们的方法在边界框的精度方面取得了38.4 \％的改进，在边界框上进行了39.1 \％的改进，以对可可的具有挑战性的小规模人群进行对现状（SOTA）的回忆（SOTA）。对于人类姿势AP评估，我们在带有单尺度测试的可可测试-DEV集中实现了新的SOTA（71.0 AP）。我们还在跨数据库评估中在Ochuman数据集上实现了最高的性能（40.3 AP）。

物体检测通常需要在现代深度学习方法中基于传统或锚盒的滑动窗口分类器。但是，这些方法中的任何一个都需要框中的繁琐配置。在本文中，我们提供了一种新的透视图，其中检测对象被激励为高电平语义特征检测任务。与边缘，角落，斑点和其他特征探测器一样，所提出的探测器扫描到全部图像的特征点，卷积自然适合该特征点。但是，与这些传统的低级功能不同，所提出的探测器用于更高级别的抽象，即我们正在寻找有物体的中心点，而现代深层模型已经能够具有如此高级别的语义抽象。除了Blob检测之外，我们还预测了中心点的尺度，这也是直接的卷积。因此，在本文中，通过卷积简化了行人和面部检测作为直接的中心和规模预测任务。这样，所提出的方法享有一个无盒设置。虽然结构简单，但它对几个具有挑战性的基准呈现竞争准确性，包括行人检测和面部检测。此外，执行交叉数据集评估，证明所提出的方法的卓越泛化能力。可以访问代码和模型（https://github.com/liuwei16/csp和https://github.com/hasanirtiza/pedestron）。

我们提出Bapose，一种新颖的自下而上的方法，实现了多人姿态估计的最先进结果。我们的最终培训框架利用了解开的多尺度瀑布架构，并将自适应卷曲融合在拥挤的场景中更准确地推断出闭塞的关键点。由BAPOSE中的解开瀑布模块获得的多尺度表示，利用级联架构中进行逐行滤波的效率，同时保持与空间金字塔配置的多尺度视图相当。我们对挑战性的Coco和Crowdose数据集的结果表明，Bapose是多人姿态估计的高效且稳健的框架，实现了最先进的准确性的显着改善。

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。

瑜伽是全球广受好评的，广泛推荐的健康生活实践。在执行瑜伽时保持正确的姿势至关重要。在这项工作中，我们采用了从人类姿势估计模型中的转移学习来提取整个人体的136个关键点，以训练一个随机的森林分类器，该分类器用于估算瑜伽室。在内部收集的内部收集的瑜伽视频数据库中评估了结果，该数据库是从4个不同的相机角度记录的51个主题。我们提出了一个三步方案，用于通过对1）看不见的帧，2）看不见的受试者进行测试来评估瑜伽分类器的普遍性。我们认为，对于大多数应用程序，对看不见的主题的验证精度和看不见的摄像头是最重要的。我们经验分析了三个公共数据集，转移学习的优势以及目标泄漏的可能性。我们进一步证明，分类精度在很大程度上取决于所采用的交叉验证方法，并且通常会产生误导。为了促进进一步的研究，我们已公开提供关键点数据集和代码。

Recently, human pose estimation mainly focuses on how to design a more effective and better deep network structure as human features extractor, and most designed feature extraction networks only introduce the position of each anatomical keypoint to guide their training process. However, we found that some human anatomical keypoints kept their topology invariance, which can help to localize them more accurately when detecting the keypoints on the feature map. But to the best of our knowledge, there is no literature that has specifically studied it. Thus, in this paper, we present a novel 2D human pose estimation method with explicit anatomical keypoints structure constraints, which introduces the topology constraint term that consisting of the differences between the distance and direction of the keypoint-to-keypoint and their groundtruth in the loss object. More importantly, our proposed model can be plugged in the most existing bottom-up or top-down human pose estimation methods and improve their performance. The extensive experiments on the benchmark dataset: COCO keypoint dataset, show that our methods perform favorably against the most existing bottom-up and top-down human pose estimation methods, especially for Lite-HRNet, when our model is plugged into it, its AP scores separately raise by 2.9\% and 3.3\% on COCO val2017 and test-dev2017 datasets.

我们提出了一种用于多实例姿态估计的端到端培训方法，称为诗人（姿势估计变压器）。将卷积神经网络与变压器编码器 - 解码器架构组合，我们将多个姿势估计从图像标记为直接设置预测问题。我们的模型能够使用双方匹配方案直接出现所有个人的姿势。诗人使用基于集的全局损失进行培训，该丢失包括关键点损耗，可见性损失和载重损失。诗歌的原因与多个检测到的个人与完整图像上下文之间的关系直接预测它们并行姿势。我们展示诗人在Coco Keypoint检测任务上实现了高精度，同时具有比其他自下而上和自上而下的方法更少的参数和更高推理速度。此外，在将诗人应用于动物姿势估计时，我们表现出了成功的转移学习。据我们所知，该模型是第一个端到端的培训多实例姿态估计方法，我们希望它将成为一种简单而有前途的替代方案。

闭塞对单眼多人3D人体姿势估计构成了极大的威胁，这是由于封闭器的形状，外观和位置方面的差异很大。尽管现有的方法试图用姿势先验/约束，数据增强或隐性推理处理遮挡，但它们仍然无法概括地看不见姿势或遮挡案例，并且在出现多人时可能会犯大错误。受到人类从可见线索推断关节的显着能力的启发，我们开发了一种方法来显式建模该过程，该过程可以显着改善有或没有遮挡的情况下，可以显着改善自下而上的多人姿势估计。首先，我们将任务分为两个子任务：可见的关键点检测和遮挡的关键点推理，并提出了深入监督的编码器蒸馏（DSED）网络以求解第二个网络。为了训练我们的模型，我们提出了一种骨骼引导的人形拟合（SSF）方法，以在现有数据集上生成伪遮挡标签，从而实现明确的遮挡推理。实验表明，从遮挡中明确学习可以改善人类姿势估计。此外，利用可见关节的特征级信息使我们可以更准确地推理遮挡关节。我们的方法的表现优于几个基准的最新自上而下和自下而上的方法。

本文介绍了使用变压器解决关键点检测和实例关联的新方法。对于自下而上的多人姿势估计模型，他们需要检测关键点并在关键点之间学习关联信息。我们认为这些问题可以完全由变压器解决。具体而言，变压器中的自我关注测量任何一对位置之间的依赖性，这可以为关键点分组提供关联信息。但是，天真的注意力模式仍然没有主观控制，因此无法保证关键点始终会参加它们所属的实例。为了解决它，我们提出了一种监督多人关键点检测和实例关联的自我关注的新方法。通过使用实例掩码来监督自我关注的实例感知，我们可以基于成对引人注定分数为其对应的实例分配检测到的关键字，而无需使用预定义的偏移量字段或嵌入像基于CNN的自下而上模型。我们方法的另一个好处是可以从监督的注意矩阵直接获得任何数量的人的实例分段结果，从而简化了像素分配管道。对Coco多人关键点检测挑战和人实例分割任务的实验证明了所提出的方法的有效性和简单性，并显示出于针对特定目的控制自我关注行为的有希望的方法。