Pedestrian detection is an important but challenging problem in computer vision, especially in human-centric tasks. Over the past decade, significant improvement has been witnessed with the help of handcrafted features and deep features. Here we present a comprehensive survey on recent advances in pedestrian detection. First, we provide a detailed review of single-spectral pedestrian detection that includes handcrafted features based methods and deep features based approaches. For handcrafted features based methods, we present an extensive review of approaches and find that handcrafted features with large freedom degrees in shape and space have better performance. In the case of deep features based approaches, we split them into pure CNN based methods and those employing both handcrafted and CNN based features. We give the statistical analysis and tendency of these methods, where feature enhanced, part-aware, and post-processing methods have attracted main attention. In addition to single-spectral pedestrian detection, we also review multi-spectral pedestrian detection, which provides more robust features for illumination variance. Furthermore, we introduce some related datasets and evaluation metrics, and a deep experimental analysis. We conclude this survey by emphasizing open problems that need to be addressed and highlighting various future directions. Researchers can track an up-to-date list at \url{https://github.com/JialeCao001/PedSurvey}.

中文翻译：

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从手工制作到行人检测的深层功能：一项调查。

行人检测是计算机视觉中一个重要但具有挑战性的问题，尤其是在以人为中心的任务中。在过去的十年中，借助手工制作的特征和深层特征，见证了显着的改进。在这里，我们对行人检测的最新进展进行了全面的调查。首先，我们详细介绍了单光谱行人检测，包括基于手工特征的方法和基于深度特征的方法。对于基于手工特征的方法，我们对方法进行了广泛的审查，发现形状和空间具有较大自由度的手工特征具有更好的性能。在基于深度特征的方法中，我们将其分为基于纯CNN的方法以及同时使用手工特征和基于CNN的特征的方法。我们对这些方法进行了统计分析和趋势分析，其中功能增强，零件感知和后处理方法引起了人们的主要关注。除了单光谱行人检测，我们还回顾了多光谱行人检测，它为照明变化提供了更强大的功能。此外，我们介绍了一些相关的数据集和评估指标以及深入的实验分析。我们通过强调需要解决的未解决问题并强调未来的各种方向来结束本调查。研究人员可以在\ url {https://github.com/JialeCao001/PedSurvey}上跟踪最新列表。我们还将回顾多光谱行人检测，它为照明变化提供了更强大的功能。此外，我们介绍了一些相关的数据集和评估指标以及深入的实验分析。我们通过强调需要解决的未解决问题并强调未来的各种方向来结束本调查。研究人员可以在\ url {https://github.com/JialeCao001/PedSurvey}上跟踪最新列表。我们还将回顾多光谱行人检测，它为照明变化提供了更强大的功能。此外，我们介绍了一些相关的数据集和评估指标以及深入的实验分析。我们通过强调需要解决的未解决问题并强调未来的各种方向来结束本调查。研究人员可以在\ url {https://github.com/JialeCao001/PedSurvey}上跟踪最新列表。