现代卷积神经网络（CNN）的面部探测器由于大量注释的数据集而取得了巨大的进步。但是，以高检测置信度未对准结果，但定位精度较低，限制了检测性能的进一步改善。在本文中，作者首先预测了训练集本身的高置信度检测结果。令人惊讶的是，其中相当一部分存在于同一未对准问题中。然后，作者仔细检查了这些案例，并指出注释未对准是主要原因。后来，对预测和注释的边界盒之间的替代合理性进行了全面讨论。最后，作者提出了一种新颖的边界盒深校准（BDC）方法，以通过模型预测的边界盒合理地替换未对准的注释，并为训练集提供校准的注释。在多个检测器和两个流行的基准数据集上进行了广泛的实验，显示了BDC对提高模型的精度和召回率的有效性，而无需添加额外的推理时间和记忆消耗。我们简单有效的方法为改善面部检测提供了一种一般策略，尤其是在实时情况下轻巧检测器的一般策略。

面部检测是为了在图像中搜索面部的所有可能区域，并且如果有任何情况，则定位面部。包括面部识别，面部表情识别，面部跟踪和头部姿势估计的许多应用假设面部的位置和尺寸在图像中是已知的。近几十年来，研究人员从Viola-Jones脸上检测器创造了许多典型和有效的面部探测器到当前的基于CNN的CNN。然而，随着图像和视频的巨大增加，具有面部刻度的变化，外观，表达，遮挡和姿势，传统的面部探测器被挑战来检测野外面孔的各种“脸部。深度学习技术的出现带来了非凡的检测突破，以及计算的价格相当大的价格。本文介绍了代表性的深度学习的方法，并在准确性和效率方面提出了深度和全面的分析。我们进一步比较并讨论了流行的并挑战数据集及其评估指标。进行了几种成功的基于深度学习的面部探测器的全面比较，以使用两个度量来揭示其效率：拖鞋和延迟。本文可以指导为不同应用选择合适的面部探测器，也可以开发更高效和准确的探测器。

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）。

随着服务机器人和监控摄像头的出现，近年来野外的动态面部识别（DFR）受到了很多关注。面部检测和头部姿势估计是DFR的两个重要步骤。经常，在面部检测后估计姿势。然而，这种顺序计算导致更高的延迟。在本文中，我们提出了一种低延迟和轻量级网络，用于同时脸部检测，地标定位和头部姿势估计。灵感来自观察，以大角度定位面部的面部地标更具挑战性，提出了一个姿势损失来限制学习。此外，我们还提出了不确定性的多任务损失，以便自动学习各个任务的权重。另一个挑战是，机器人通常使用武器基的计算核心等低计算单元，我们经常需要使用轻量级网络而不是沉重的网络，这导致性能下降，特别是对于小型和硬面。在本文中，我们提出了在线反馈采样来增加不同尺度的培训样本，这会自动增加培训数据的多样性。通过验证常用的更广泛的脸，AFLW和AFLW2000数据集，结果表明，该方法在低计算资源中实现了最先进的性能。代码和数据将在https://github.com/lyp-deeplearning/mos-multi-task-face-detect上使用。

物体检测在计算机视觉中取得了巨大的进步。具有外观降级的小物体检测是一个突出的挑战，特别是对于鸟瞰观察。为了收集足够的阳性/阴性样本进行启发式训练，大多数物体探测器预设区域锚，以便将交叉联盟（iou）计算在地面判处符号数据上。在这种情况下，小物体经常被遗弃或误标定。在本文中，我们提出了一种有效的动态增强锚（DEA）网络，用于构建新颖的训练样本发生器。与其他最先进的技术不同，所提出的网络利用样品鉴别器来实现基于锚的单元和无锚单元之间的交互式样本筛选，以产生符合资格的样本。此外，通过基于保守的基于锚的推理方案的多任务联合训练增强了所提出的模型的性能，同时降低计算复杂性。所提出的方案支持定向和水平对象检测任务。对两个具有挑战性的空中基准（即，DotA和HRSC2016）的广泛实验表明，我们的方法以适度推理速度和用于训练的计算开销的准确性实现最先进的性能。在DotA上，我们的DEA-NET与ROI变压器的基线集成了0.40％平均平均精度（MAP）的先进方法，以便用较弱的骨干网（Resnet-101 VS Resnet-152）和3.08％平均 - 平均精度（MAP），具有相同骨干网的水平对象检测。此外，我们的DEA网与重新排列的基线一体化实现最先进的性能80.37％。在HRSC2016上，它仅使用3个水平锚点超过1.1％的最佳型号。

无锚的检测器基本上将对象检测作为密集的分类和回归。对于流行的无锚检测器，通常是引入单个预测分支来估计本地化的质量。当我们深入研究分类和质量估计的实践时，会观察到以下不一致之处。首先，对于某些分配了完全不同标签的相邻样品，训练有素的模型将产生相似的分类分数。这违反了训练目标并导致绩效退化。其次，发现检测到具有较高信心的边界框与相应的地面真相具有较小的重叠。准确的局部边界框将被非最大抑制（NMS）过程中的精确量抑制。为了解决不一致问题，提出了动态平滑标签分配（DSLA）方法。基于最初在FCO中开发的中心概念，提出了平稳的分配策略。在[0，1]中将标签平滑至连续值，以在正样品和负样品之间稳定过渡。联合（IOU）在训练过程中会动态预测，并与平滑标签结合。分配动态平滑标签以监督分类分支。在这样的监督下，质量估计分支自然合并为分类分支，这简化了无锚探测器的体系结构。全面的实验是在MS Coco基准上进行的。已经证明，DSLA可以通过减轻上述无锚固探测器的不一致来显着提高检测准确性。我们的代码在https://github.com/yonghaohe/dsla上发布。

2019年冠状病毒为全球社会稳定和公共卫生带来了严重的挑战。遏制流行病的一种有效方法是要求人们在公共场所戴口罩，并通过使用合适的自动探测器来监视戴口罩状态。但是，现有的基于深度学习的模型努力同时达到高精度和实时性能的要求。为了解决这个问题，我们提出了基于Yolov5的改进的轻质面膜探测器，该检测器可以实现精确和速度的良好平衡。首先，提出了将ShuffleNetV2网络与协调注意机制相结合的新型骨干轮弹工具作为骨干。之后，将有效的路径攻击网络BIFPN作为特征融合颈应用。此外，在模型训练阶段，定位损失被α-CIOU取代，以获得更高质量的锚。还利用了一些有价值的策略，例如数据增强，自适应图像缩放和锚点群集操作。 Aizoo面膜数据集的实验结果显示了所提出模型的优越性。与原始的Yolov5相比，提出的模型将推理速度提高28.3％，同时仍将精度提高0.58％。与其他七个现有型号相比，它的最佳平均平均精度为95.2％，比基线高4.4％。

近年来使用卷积神经网络对近年来的脸部检测进行了巨大进展。虽然许多面部探测器使用指定用于检测面的设计，但我们将面部检测视为通用对象检测任务。我们基于YOLOV5对象检测器实现了面部探测器，并调用它YOLO5FACE。我们对YOLOV5进行了一些关键修改，并优化了面部检测。这些修改包括在SPP中使用较小尺寸内核在骨干内使用杆块添加五点地标回归头，并在平移块中添加P6输出。我们从超大型模型设计不同型号大小的探测器，以实现对嵌入或移动设备的实时检测的超小型模型的最佳性能。实验结果在viderface数据集上显示，在VGA图像上，我们的脸部探测器可以在几乎所有简单，介质和硬的子集中实现最先进的性能，超过更复杂的指定面检测器。代码可用于\ url {https://github.com/deepcam-cn/yolov5-face}

受益于通用对象探测器的开创性设计，面部检测领域已经取得了重大成就。通常，骨干，特征金字塔层和面部检测器内的检测头模块的架构都同化了一般物体探测器的优异体验。然而，几种有效方法，包括标签分配和尺度级数据增强策略\脚注{丰富了培训数据的规模分布，以解决尺度方差挑战。}，在直接施加面部探测器时，不能保持一致的优势。具体地，前者策略涉及庞大的超参数，后者患有不同检测任务之间的规模分布偏差的挑战，这都限制了它们的概括能力。此外，为了提供用于面部下游任务的精确面边界盒，面部检测器要求消除误报。因此，对推进面部检测器需要对标签分配，尺度级数据增强和减少误报的实用解决方案。在本文中，我们专注于解决三个上述挑战，即退出方法难以结束并呈现新的面部探测器，称为摩戈。在我们的MOGFACE中，三个关键组件，自适应在线增量锚挖掘策略，选择性缩放增强策略和分层上下文感知模块，分别提出促进面部检测的性能。最后，据我们所知，我们的摩日脸是更广泛的面部领导板上最好的面部探测器，在不同的测试场景中实现所有冠军。代码可在https://github.com/idstcv/mogface上获得

Though tremendous strides have been made in uncontrolled face detection, accurate and efficient 2D face alignment and 3D face reconstruction in-the-wild remain an open challenge. In this paper, we present a novel singleshot, multi-level face localisation method, named Reti-naFace, which unifies face box prediction, 2D facial landmark localisation and 3D vertices regression under one common target: point regression on the image plane. To fill the data gap, we manually annotated five facial landmarks on the WIDER FACE dataset and employed a semiautomatic annotation pipeline to generate 3D vertices for face images from the WIDER FACE, AFLW and FDDB datasets. Based on extra annotations, we propose a mutually beneficial regression target for 3D face reconstruction, that is predicting 3D vertices projected on the image plane constrained by a common 3D topology. The proposed 3D face reconstruction branch can be easily incorporated, without any optimisation difficulty, in parallel with the existing box and 2D landmark regression branches during joint training. Extensive experimental results show that Reti-naFace can simultaneously achieve stable face detection, accurate 2D face alignment and robust 3D face reconstruction while being efficient through single-shot inference.

近年来，基于深度学习的面部检测算法取得了长足的进步。这些算法通常可以分为两类，即诸如更快的R-CNN和像Yolo这样的单阶段检测器之类的两个阶段检测器。由于准确性和速度之间的平衡更好，因此在许多应用中广泛使用了一阶段探测器。在本文中，我们提出了一个基于一阶段检测器Yolov5的实时面部检测器，名为Yolo-Facev2。我们设计一个称为RFE的接收场增强模块，以增强小面的接受场，并使用NWD损失来弥补IOU对微小物体的位置偏差的敏感性。对于面部阻塞，我们提出了一个名为Seam的注意模块，并引入了排斥损失以解决它。此外，我们使用重量函数幻灯片来解决简单和硬样品之间的不平衡，并使用有效的接收场的信息来设计锚。宽面数据集上的实验结果表明，在所有简单，中和硬子集中都可以找到我们的面部检测器及其变体的表现及其变体。源代码https://github.com/krasjet-yu/yolo-facev2

Modern CNN-based object detectors rely on bounding box regression and non-maximum suppression to localize objects. While the probabilities for class labels naturally reflect classification confidence, localization confidence is absent. This makes properly localized bounding boxes degenerate during iterative regression or even suppressed during NMS. In the paper we propose IoU-Net learning to predict the IoU between each detected bounding box and the matched ground-truth. The network acquires this confidence of localization, which improves the NMS procedure by preserving accurately localized bounding boxes. Furthermore, an optimization-based bounding box refinement method is proposed, where the predicted IoU is formulated as the objective. Extensive experiments on the MS-COCO dataset show the effectiveness of IoU-Net, as well as its compatibility with and adaptivity to several state-of-the-art object detectors.

旋转不变的面部检测，即用任意旋转平面（RIP）角度的检测面，广泛需要在无约束的应用中被广泛地需要，但由于面部出现的较大变化，仍然仍然是一个具有挑战性的任务。大多数现有方法符合速度或准确性以处理大的撕裂变体。为了更有效地解决这个问题，我们提出了逐步校准网络（PCN）以粗略的方式执行旋转不变的面部检测。 PCN由三个阶段组成，每个阶段不仅将面与非面孔区分开，而且还校准了每个面部候选者的RIP方向逐渐直立。通过将校准过程划分为几个渐进步骤，并且仅预测早期阶段中的粗定向，PCN可以实现精确且快速校准。通过对脸部与逐渐减小的RIP范围进行二进制分类，PCN可以准确地检测满360 ^ {\ rIC} $ RIP角度的面部。这种设计导致实时旋转不变面检测器。在野外的多面向FDDB的实验和疯狂旋转面的较宽面的具有挑战性的子集表明我们的PCN实现了非常有希望的性能。

We propose a fully convolutional one-stage object detector (FCOS) to solve object detection in a per-pixel prediction fashion, analogue to semantic segmentation. Almost all state-of-the-art object detectors such as RetinaNet, SSD, YOLOv3, and Faster R-CNN rely on pre-defined anchor boxes. In contrast, our proposed detector FCOS is anchor box free, as well as proposal free. By eliminating the predefined set of anchor boxes, FCOS completely avoids the complicated computation related to anchor boxes such as calculating overlapping during training. More importantly, we also avoid all hyper-parameters related to anchor boxes, which are often very sensitive to the final detection performance. With the only post-processing non-maximum suppression (NMS), FCOS with ResNeXt-64x4d-101 achieves 44.7% in AP with single-model and single-scale testing, surpassing previous one-stage detectors with the advantage of being much simpler. For the first time, we demonstrate a much simpler and flexible detection framework achieving improved detection accuracy. We hope that the proposed FCOS framework can serve as a simple and strong alternative for many other instance-level tasks. Code is available at:tinyurl.com/FCOSv1

Due to object detection's close relationship with video analysis and image understanding, it has attracted much research attention in recent years. Traditional object detection methods are built on handcrafted features and shallow trainable architectures. Their performance easily stagnates by constructing complex ensembles which combine multiple low-level image features with high-level context from object detectors and scene classifiers. With the rapid development in deep learning, more powerful tools, which are able to learn semantic, high-level, deeper features, are introduced to address the problems existing in traditional architectures. These models behave differently in network architecture, training strategy and optimization function, etc. In this paper, we provide a review on deep learning based object detection frameworks. Our review begins with a brief introduction on the history of deep learning and its representative tool, namely Convolutional Neural Network (CNN). Then we focus on typical generic object detection architectures along with some modifications and useful tricks to improve detection performance further. As distinct specific detection tasks exhibit different characteristics, we also briefly survey several specific tasks, including salient object detection, face detection and pedestrian detection. Experimental analyses are also provided to compare various methods and draw some meaningful conclusions. Finally, several promising directions and tasks are provided to serve as guidelines for future work in both object detection and relevant neural network based learning systems.

Face detection is one of the most studied topics in the computer vision community. Much of the progresses have been made by the availability of face detection benchmark datasets. We show that there is a gap between current face detection performance and the real world requirements. To facilitate future face detection research, we introduce the WIDER FACE dataset, which is 10 times larger than existing datasets. The dataset contains rich annotations, including occlusions, poses, event categories, and face bounding boxes. Faces in the proposed dataset are extremely challenging due to large variations in scale, pose and occlusion, as shown in Fig. 1. Furthermore, we show that WIDER FACE dataset is an effective training source for face detection. We benchmark several representative detection systems, providing an overview of state-of-the-art performance and propose a solution to deal with large scale variation. Finally, we discuss common failure cases that worth to be further investigated. Dataset can be downloaded at: mmlab.ie.cuhk.edu.hk/projects/WIDERFace

标签分配在现代对象检测模型中起着重要作用。检测模型可能会通过不同的标签分配策略产生完全不同的性能。对于基于锚的检测模型，锚点及其相应的地面真实边界框之间的IO（与联合的交点）是关键要素，因为正面样品和负样品除以IOU阈值。早期对象探测器仅利用所有训练样本的固定阈值，而最近的检测算法则基于基于IOUS到地面真相框的分布而着重于自适应阈值。在本文中，我们介绍了一种简单的同时有效的方法，可以根据预测的培训状态动态执行标签分配。通过在标签分配中引入预测，选择了更高的地面真相对象的高质量样本作为正样本，这可以减少分类得分和IOU分数之间的差异，并生成更高质量的边界框。我们的方法显示了使用自适应标签分配算法和这些正面样本的下限框损失的检测模型的性能的改进，这表明将更多具有较高质量预测盒的样品选择为阳性。

The detection of human body and its related parts (e.g., face, head or hands) have been intensively studied and greatly improved since the breakthrough of deep CNNs. However, most of these detectors are trained independently, making it a challenging task to associate detected body parts with people. This paper focuses on the problem of joint detection of human body and its corresponding parts. Specifically, we propose a novel extended object representation that integrates the center location offsets of body or its parts, and construct a dense single-stage anchor-based Body-Part Joint Detector (BPJDet). Body-part associations in BPJDet are embedded into the unified representation which contains both the semantic and geometric information. Therefore, BPJDet does not suffer from error-prone association post-matching, and has a better accuracy-speed trade-off. Furthermore, BPJDet can be seamlessly generalized to jointly detect any body part. To verify the effectiveness and superiority of our method, we conduct extensive experiments on the CityPersons, CrowdHuman and BodyHands datasets. The proposed BPJDet detector achieves state-of-the-art association performance on these three benchmarks while maintains high accuracy of detection. Code will be released to facilitate further studies.

Single-frame InfraRed Small Target (SIRST) detection has been a challenging task due to a lack of inherent characteristics, imprecise bounding box regression, a scarcity of real-world datasets, and sensitive localization evaluation. In this paper, we propose a comprehensive solution to these challenges. First, we find that the existing anchor-free label assignment method is prone to mislabeling small targets as background, leading to their omission by detectors. To overcome this issue, we propose an all-scale pseudo-box-based label assignment scheme that relaxes the constraints on scale and decouples the spatial assignment from the size of the ground-truth target. Second, motivated by the structured prior of feature pyramids, we introduce the one-stage cascade refinement network (OSCAR), which uses the high-level head as soft proposals for the low-level refinement head. This allows OSCAR to process the same target in a cascade coarse-to-fine manner. Finally, we present a new research benchmark for infrared small target detection, consisting of the SIRST-V2 dataset of real-world, high-resolution single-frame targets, the normalized contrast evaluation metric, and the DeepInfrared toolkit for detection. We conduct extensive ablation studies to evaluate the components of OSCAR and compare its performance to state-of-the-art model-driven and data-driven methods on the SIRST-V2 benchmark. Our results demonstrate that a top-down cascade refinement framework can improve the accuracy of infrared small target detection without sacrificing efficiency. The DeepInfrared toolkit, dataset, and trained models are available at https://github.com/YimianDai/open-deepinfrared to advance further research in this field.