This paper addresses the challenge of 6DoF pose estimation from a single RGB image under severe occlusion or truncation. Many recent works have shown that a two-stage approach, which first detects keypoints and then solves a Perspective-n-Point (PnP) problem for pose estimation, achieves remarkable performance. However, most of these methods only localize a set of sparse keypoints by regressing their image coordinates or heatmaps, which are sensitive to occlusion and truncation. Instead, we introduce a Pixel-wise Voting Network (PVNet) to regress pixel-wise unit vectors pointing to the keypoints and use these vectors to vote for keypoint locations using RANSAC. This creates a flexible representation for localizing occluded or truncated keypoints. Another important feature of this representation is that it provides uncertainties of keypoint locations that can be further leveraged by the PnP solver. Experiments show that the proposed approach outperforms the state of the art on the LINEMOD, Occlusion LINEMOD and YCB-Video datasets by a large margin, while being efficient for real-time pose estimation. We further create a Truncation LINEMOD dataset to validate the robustness of our approach against truncation. The code will be avaliable at https://zju-3dv.github.io/pvnet/.

Estimating the 6D pose of known objects is important for robots to interact with the real world. The problem is challenging due to the variety of objects as well as the complexity of a scene caused by clutter and occlusions between objects. In this work, we introduce PoseCNN, a new Convolutional Neural Network for 6D object pose estimation. PoseCNN estimates the 3D translation of an object by localizing its center in the image and predicting its distance from the camera. The 3D rotation of the object is estimated by regressing to a quaternion representation. We also introduce a novel loss function that enables PoseCNN to handle symmetric objects. In addition, we contribute a large scale video dataset for 6D object pose estimation named the YCB-Video dataset. Our dataset provides accurate 6D poses of 21 objects from the YCB dataset observed in 92 videos with 133,827 frames. We conduct extensive experiments on our YCB-Video dataset and the OccludedLINEMOD dataset to show that PoseCNN is highly robust to occlusions, can handle symmetric objects, and provide accurate pose estimation using only color images as input. When using depth data to further refine the poses, our approach achieves state-of-the-art results on the challenging OccludedLINEMOD dataset. Our code and dataset are available at https://rse-lab.cs.washington.edu/projects/posecnn/.

6D object pose estimation problem has been extensively studied in the field of Computer Vision and Robotics. It has wide range of applications such as robot manipulation, augmented reality, and 3D scene understanding. With the advent of Deep Learning, many breakthroughs have been made; however, approaches continue to struggle when they encounter unseen instances, new categories, or real-world challenges such as cluttered backgrounds and occlusions. In this study, we will explore the available methods based on input modality, problem formulation, and whether it is a category-level or instance-level approach. As a part of our discussion, we will focus on how 6D object pose estimation can be used for understanding 3D scenes.

我们提出了一种基于相交的球体的新型关键点投票方案，其比现有方案更准确，并且允许较小的更多分散关键点。该方案基于点之间的距离，其作为1D数量可以比在先前的工作中的2D和3D向量和偏移量中更精确地回归，从而产生更准确的小点定位。该方案构成了RGB-D数据中的6 DOF姿势估计的所提出的RCVPOS方法的基础，这在处理闭塞时特别有效。训练CNN以估计与每个RGB像素的深度模式对应的3D点之间的距离，以及在对象帧中定义的一组3分散键点。在推断下，产生在每个3D点处的球体，其半径等于该估计距离。这些球体的表面投票给增量3D累加器空间，其峰值指示Keypoint位置。所提出的径向投票方案比以前的矢量或偏移方案更准确，并且稳健地分散关键点。实验表明，RCPOSE是高度准确和竞争的，在LineMod 99.7％和YCB-Video 97.2％数据集上实现最先进的结果，显着得分+ 7.9％（71.1％）比以前的挑战遮挡Linemod上的方法数据集。

Estimating 6D poses of objects from images is an important problem in various applications such as robot manipulation and virtual reality. While direct regression of images to object poses has limited accuracy, matching rendered images of an object against the input image can produce accurate results. In this work, we propose a novel deep neural network for 6D pose matching named DeepIM. Given an initial pose estimation, our network is able to iteratively refine the pose by matching the rendered image against the observed image. The network is trained to predict a relative pose transformation using a disentangled representation of 3D location and 3D orientation and an iterative training process. Experiments on two commonly used benchmarks for 6D pose estimation demonstrate that DeepIM achieves large improvements over stateof-the-art methods. We furthermore show that DeepIM is able to match previously unseen objects.

We propose a single-shot approach for simultaneously detecting an object in an RGB image and predicting its 6D pose without requiring multiple stages or having to examine multiple hypotheses. Unlike a recently proposed single-shot technique for this task [11] that only predicts an approximate 6D pose that must then be refined, ours is accurate enough not to require additional post-processing. As a result, it is much faster -50 fps on a Titan X (Pascal) GPU -and more suitable for real-time processing. The key component of our method is a new CNN architecture inspired by [28,29] that directly predicts the 2D image locations of the projected vertices of the object's 3D bounding box. The object's 6D pose is then estimated using a PnP algorithm.For single object and multiple object pose estimation on the LINEMOD and OCCLUSION datasets, our approach substantially outperforms other recent 26] when they are all used without postprocessing. During post-processing, a pose refinement step can be used to boost the accuracy of these two methods, but at 10 fps or less, they are much slower than our method.

很少有6D姿势估计方法使用骨干网络从RGB和深度图像中提取功能，而Uni6D是这样做的先驱。我们发现UNI6D中性能限制的主要原因是实例外部和实例 - 内噪声。 uni6d不可避免地会由于其固有的直接管道设计而从接收场中的背景像素引入实例外部噪声，并忽略了输入深度数据中的实例 - 内侧噪声。在这项工作中，我们提出了一种两步的denoising方法，以处理UNI6D中上述噪声。在第一步中，实例分割网络用于裁剪和掩盖实例，以消除非实施区域的噪声。在第二步中，提出了一个轻巧的深度剥夺模块，以校准深度特征，然后再将其输入姿势回归网络。广泛的实验表明，我们称为uni6dv2的方法能够有效，稳健地消除噪声，在不牺牲过多的推理效率的情况下超过UNI6D。它还减少了对需要昂贵标签的注释真实数据的需求。

从RGB-D图像中对刚性对象的6D姿势估计对于机器人技术中的对象抓握和操纵至关重要。尽管RGB通道和深度（d）通道通常是互补的，分别提供了外观和几何信息，但如何完全从两个跨模式数据中完全受益仍然是非平凡的。从简单而新的观察结果来看，当对象旋转时，其语义标签是姿势不变的，而其关键点偏移方向是姿势的变体。为此，我们提出了So（3）pose，这是一个新的表示学习网络，可以探索SO（3）equivariant和So（3） - 从深度通道中进行姿势估计的特征。 SO（3） - 激素特征有助于学习更独特的表示，以分割来自RGB通道外观相似的对象。 SO（3） - 等级特征与RGB功能通信，以推导（缺失的）几何形状，以检测从深度通道的反射表面的对象的关键点。与大多数现有的姿势估计方法不同，我们的SO（3） - 不仅可以实现RGB和深度渠道之间的信息通信，而且自然会吸收SO（3） - 等级的几何学知识，从深度图像中，导致更好的外观和更好的外观和更好几何表示学习。综合实验表明，我们的方法在三个基准测试中实现了最先进的性能。

A key technical challenge in performing 6D object pose estimation from RGB-D image is to fully leverage the two complementary data sources. Prior works either extract information from the RGB image and depth separately or use costly post-processing steps, limiting their performances in highly cluttered scenes and real-time applications. In this work, we present DenseFusion, a generic framework for estimating 6D pose of a set of known objects from RGB-D images. DenseFusion is a heterogeneous architecture that processes the two data sources individually and uses a novel dense fusion network to extract pixel-wise dense feature embedding, from which the pose is estimated. Furthermore, we integrate an end-to-end iterative pose refinement procedure that further improves the pose estimation while achieving near real-time inference. Our experiments show that our method outperforms state-of-the-art approaches in two datasets, YCB-Video and LineMOD. We also deploy our proposed method to a real robot to grasp and manipulate objects based on the estimated pose. Our code and video are available at https://sites.google.com/view/densefusion/.

We introduce a novel method for 3D object detection and pose estimation from color images only. We first use segmentation to detect the objects of interest in 2D even in presence of partial occlusions and cluttered background. By contrast with recent patch-based methods, we rely on a "holistic" approach: We apply to the detected objects a Convolutional Neural Network (CNN) trained to predict their 3D poses in the form of 2D projections of the corners of their 3D bounding boxes. This, however, is not sufficient for handling objects from the recent T-LESS dataset: These objects exhibit an axis of rotational symmetry, and the similarity of two images of such an object under two different poses makes training the CNN challenging. We solve this problem by restricting the range of poses used for training, and by introducing a classifier to identify the range of a pose at run-time before estimating it. We also use an optional additional step that refines the predicted poses. We improve the state-of-the-art on the LINEMOD dataset from 73.7% [2] to 89.3% of correctly registered RGB frames. We are also the first to report results on the Occlusion dataset [1] using color images only. We obtain 54% of frames passing the Pose 6D criterion on average on several sequences of the T-LESS dataset, compared to the 67% of the state-of-the-art [10] on the same sequences which uses both color and depth. The full approach is also scalable, as a single network can be trained for multiple objects simultaneously.

Applications in the field of augmented reality or robotics often require joint localisation and 6D pose estimation of multiple objects. However, most algorithms need one network per object class to be trained in order to provide the best results. Analysing all visible objects demands multiple inferences, which is memory and time-consuming. We present a new single-stage architecture called CASAPose that determines 2D-3D correspondences for pose estimation of multiple different objects in RGB images in one pass. It is fast and memory efficient, and achieves high accuracy for multiple objects by exploiting the output of a semantic segmentation decoder as control input to a keypoint recognition decoder via local class-adaptive normalisation. Our new differentiable regression of keypoint locations significantly contributes to a faster closing of the domain gap between real test and synthetic training data. We apply segmentation-aware convolutions and upsampling operations to increase the focus inside the object mask and to reduce mutual interference of occluding objects. For each inserted object, the network grows by only one output segmentation map and a negligible number of parameters. We outperform state-of-the-art approaches in challenging multi-object scenes with inter-object occlusion and synthetic training.

我们提出了一个基于按键的对象级别的SLAM框架，该框架可以为对称和不对称对象提供全球一致的6DOF姿势估计。据我们所知，我们的系统是最早利用来自SLAM的相机姿势信息的系统之一，以提供先验知识，以跟踪对称对象的关键点 - 确保新测量与当前的3D场景一致。此外，我们的语义关键点网络经过训练，可以预测捕获预测的真实错误的关键点的高斯协方差，因此不仅可以作为系统优化问题中残留物的权重，而且还可以作为检测手段有害的统计异常值，而无需选择手动阈值。实验表明，我们的方法以6DOF对象姿势估算和实时速度为最先进的状态提供了竞争性能。我们的代码，预培训模型和关键点标签可用https://github.com/rpng/suo_slam。

估计对象的6D姿势是必不可少的计算机视觉任务。但是，大多数常规方法从单个角度依赖相机数据，因此遭受遮挡。我们通过称为MV6D的新型多视图6D姿势估计方法克服了这个问题，该方法从多个角度根据RGB-D图像准确地预测了混乱场景中所有对象的6D姿势。我们将方法以PVN3D网络为基础，该网络使用单个RGB-D图像来预测目标对象的关键点。我们通过从多个视图中使用组合点云来扩展此方法，并将每个视图中的图像与密集层层融合。与当前的多视图检测网络（例如Cosypose）相反，我们的MV6D可以以端到端的方式学习多个观点的融合，并且不需要多个预测阶段或随后对预测的微调。此外，我们介绍了三个新颖的影像学数据集，这些数据集具有沉重的遮挡的混乱场景。所有这些都从多个角度包含RGB-D图像，例如语义分割和6D姿势估计。即使在摄像头不正确的情况下，MV6D也明显优于多视图6D姿势估计中最新的姿势估计。此外，我们表明我们的方法对动态相机设置具有强大的态度，并且其准确性随着越来越多的观点而逐渐增加。

我们提出了一种称为DPODV2（密集姿势对象检测器）的三个阶段6 DOF对象检测方法，该方法依赖于致密的对应关系。我们将2D对象检测器与密集的对应关系网络和多视图姿势细化方法相结合，以估计完整的6 DOF姿势。与通常仅限于单眼RGB图像的其他深度学习方法不同，我们提出了一个统一的深度学习网络，允许使用不同的成像方式（RGB或DEPTH）。此外，我们提出了一种基于可区分渲染的新型姿势改进方法。主要概念是在多个视图中比较预测并渲染对应关系，以获得与所有视图中预测的对应关系一致的姿势。我们提出的方法对受控设置中的不同数据方式和培训数据类型进行了严格的评估。主要结论是，RGB在对应性估计中表现出色，而如果有良好的3D-3D对应关系，则深度有助于姿势精度。自然，他们的组合可以实现总体最佳性能。我们进行广泛的评估和消融研究，以分析和验证几个具有挑战性的数据集的结果。 DPODV2在所有这些方面都取得了出色的成果，同时仍然保持快速和可扩展性，独立于使用的数据模式和培训数据的类型

传统的3D人姿态估计依赖于首次检测2D身体键盘，然后求解2D到3D对应问题。提高有希望的结果，该学习范例高度依赖于2D关键点检测器的质量，这不可避免地易于闭塞和堵塞-of-image缺席。在本文中，我们提出了一种新颖的姿势定向网（PONET），其能够仅通过学习方向估计3D姿势，因此在没有图像证据的情况下绕过错误易于keypoint检测器。对于具有部分不可见的四肢的图像，Ponet通过利用本地图像证据来恢复3D姿势来估计这些肢体的3D方向。通过利用完全看不见的四肢来说，Ponet甚至可以从完全看不见的四肢的图像中推断出完整的3D姿势。可见肢体之间的取向相关性以补充估计的姿势，进一步提高了3D姿态估计的鲁棒性。我们在多个数据集中评估我们的方法，包括Human3.6M，MPII，MPI-INF-3DHP和3DPW。我们的方法在理想设置中实现了与最先进的技术的结果，但显着消除了对关键点检测器和相应的计算负担的依赖性。在截断和擦除等方面的高度挑战性方案中，我们的方法稳健地表现得非常强大，与本领域的状态相比，展示其对现实世界应用的可能性。

本文介绍了一个有效的对称性和无对应框架，称为SC6D，对于单个单眼RGB图像的6D对象姿势估计。SC6D既不需要对象的3D CAD模型，也不需要对称对称的任何先验知识。姿势估计分解为三个子任务：a）对象3D旋转表示学习和匹配；b）估计对象中心的2D位置；和c）通过分类的比例不变距离估计（沿Z轴的翻译）。SC6D在三个基准数据集（T-less，YCB-V和ITODD）上进行了评估，并在T-less数据集中获得最先进的性能。此外，SC6D在计算上比以前的最新方法Surfemb更有效。实施和预培训模型可在https://github.com/dingdingcai/sc6d-pose上公开获得。

从RGB图像中对刚性对象进行精确的6D构成估计是机器人技术和增强现实中的一项至关重要的任务。为了解决这个问题，我们提出了DeepRM，这是一种新型的经过精炼的新型经过的网络体系结构。 DeepRM利用初始粗姿势估计来渲染目标对象的合成图像。然后将渲染图像与观察到的图像匹配，以预测更新先前姿势估计值的刚性变换。重复此过程以逐步完善每次迭代的估计值。 LSTM单元用于通过每个完善步骤来传播信息，从而显着提高整体性能。与许多基于2阶段的透视点解决方案相反，DEEPRM是端到端训练的，并使用可扩展的主链，可以通过单个参数调整以提高准确性和效率。在训练过程中，添加了多尺度的光流头，以预测观察到的和合成图像之间的光流。光流预测稳定了训练过程，并强制学习与姿势估计任务相关的功能。我们的结果表明，DEEPRM在两个广泛接受的具有挑战性的数据集上实现了最先进的性能。

在许多机器人应用中，要执行已知，刚体对象及其随后的抓握的6多-DOF姿势估计的环境设置几乎保持不变，甚至可能是机器人事先知道的。在本文中，我们将此问题称为特定实例的姿势估计：只有在有限的一组熟悉的情况下，该机器人将以高度准确性估算姿势。场景中的微小变化，包括照明条件和背景外观的变化，是可以接受的，但没有预期的改变。为此，我们提出了一种方法，可以快速训练和部署管道，以估算单个RGB图像的对象的连续6-DOF姿势。关键的想法是利用已知的相机姿势和刚性的身体几何形状部分自动化大型标记数据集的生成。然后，数据集以及足够的域随机化来监督深度神经网络的培训，以预测语义关键。在实验上，我们证明了我们提出的方法的便利性和有效性，以准确估计物体姿势，仅需要少量的手动注释才能进行训练。

We introduce an approach for recovering the 6D pose of multiple known objects in a scene captured by a set of input images with unknown camera viewpoints. First, we present a single-view single-object 6D pose estimation method, which we use to generate 6D object pose hypotheses. Second, we develop a robust method for matching individual 6D object pose hypotheses across different input images in order to jointly estimate camera viewpoints and 6D poses of all objects in a single consistent scene. Our approach explicitly handles object symmetries, does not require depth measurements, is robust to missing or incorrect object hypotheses, and automatically recovers the number of objects in the scene. Third, we develop a method for global scene refinement given multiple object hypotheses and their correspondences across views. This is achieved by solving an object-level bundle adjustment problem that refines the poses of cameras and objects to minimize the reprojection error in all views. We demonstrate that the proposed method, dubbed Cosy-Pose, outperforms current state-of-the-art results for single-view and multi-view 6D object pose estimation by a large margin on two challenging benchmarks: the YCB-Video and T-LESS datasets. Code and pre-trained models are available on the project webpage. 5

对象姿态估计有多个重要应用，例如机器人抓握和增强现实。我们提出了一种估计了提高当前提案的准确性的6D对象的6D姿势，仍然可以实时使用。我们的方法使用RGB-D数据作为段对象的输入并估计它们的姿势。它使用具有多个头部的神经网络，一个头估计对象分类并生成掩码，第二估计转换向量的值，最后一个头估计表示对象旋转的四元轴的值。这些头部利用特征提取和特征融合期间使用的金字塔架构。我们的方法可以实时使用，其低推理时间为0.12秒并具有高精度。通过这种快速推理和良好准确性的组合，可以在机器人挑选和放置任务和/或增强现实应用中使用我们的方法。