一种基于卷积神经网络深度学习的人体行为识别方法

为提高基于智能终端的人体行为识别的准确率,提出一种基于卷积神经网络深度学习人体行为识别方法。该方法将原始数据进行简单处理,直接作为输入数据输入到卷积神经网络中,由卷积神经网络进行局部特征分析,得到特征输出项,直接输入到Softmax分类器中,可识别走路、跑步、上下楼梯、站立等5种动作。 对比实验结果表明,其对不同的实验者的识别率达到84.8%,证明了该方法的有效性。     

A General Method for Sensor Planning in Multi-Sensor Systems: Extension to Random Occlusion

Systems utilizing multiple sensors are required in many domains. In this paper, we specifically concern ourselves with applications where dynamic objects appear randomly and the system is employed to obtain some user-specified characteristics of such objects. For such systems, we deal with the tasks of determining measures for evaluating their performance and of determining good sensor configurations that would maximize such measures for better system performance. We introduce a constraint in sensor planning that has not been addressed earlier: visibility in the presence of random occluding objects. occlusion causes random loss of object capture from certain necessitates the use of other sensors that have visibility of this object. Two techniques are developed to analyze such visibility constraints: a probabilistic approach to determine “average” visibility rates and a deterministic approach to address worst-case scenarios. Apart from this constraint, other important constraints to be considered include image resolution, field of view, capture orientation, and algorithmic constraints such as stereo matching and background appearance. Integration of such constraints is performed via the development of a probabilistic framework that allows one to reason about different occlusion events and integrates different multi-view capture and visibility constraints in a natural way. Integration of the thus obtained capture quality measure across the region of interest yields a measure for the effectiveness of a sensor configuration and maximization of such measure yields sensor configurations that are best suited for a given scenario. The approach can be customized for use in many multi-sensor applications and our contribution is especially significant for those that involve randomly occurring objects capable of occluding each other. These include security systems for surveillance in public places, industrial automation and traffic monitoring. Several examples illustrate such versatility by application of our approach to a diverse set of different and sometimes multiple system objectives. Most of this work was done while A. Mittal was with Real-Time Vision and Modeling Department, Siemens Corporate Research, Princeton, NJ 08540.     

基于主元分析法的行为识别

通过研究,建立了一个基于主元分析的识别办体行为的系统,其方法是通过在Ｈ、Ｓ、Ｉ颜色空间对皮肤颜色建立高期模型,结合运动限制和区域连续性,系统地分割并跟踪人脸和双手,然后,在ＰＣＡ框架下,表示脸和手的运动参数曲线,并和范例进行匹配,这种通过对行为在时空域变化的建模方法,能在行为主体和成象条件有变化的情况下识别行为,以太极拳式谡列,来验证方法和系统的效果,实验结果证明了此方法误识率低,有一定的鲁棒性,     

基于多层动态贝叶斯网络的人的行为多尺度分析及识别方法

人的行为识别是视频内容分析和计算机视觉领域中的一个重要问题. 在分析了人的行为包含多个尺度运动细节的基础上, 提出了一种分层且带驻留时间状态的动态贝叶斯网络(Hierarchical durational-state dynamic Bayesian network, HDS-DBN). HDS-DBN含有多层状态, 能够较好地表示人的行为包含的多尺度运动细节. 我们针对单人行为和两人交互行为进行了识别, 实验结果表明该方法具有较高的识别率, 并且在有噪声存在或信息缺失等不确定情况下均具有较好的鲁棒性. 实验结果表明 HDS-DBN 模型确实能够较好地表达行为中的多尺度运动细节.     

基于监控系统的人体行为识别技术研究

针对传统行为识别技术实时性、鲁棒性较差等问题,提出了一种高效鲁棒性的人体行为识别算法。通过基于Meanshift和Kalman滤波相结合的跟踪算法来跟踪定位人体目标;利用肢体特征和区域特征来提取运动特征;利用基于OAA的支持向量机分类识别。仿真实验表明,该算法实时性好、鲁棒性高,能有效应用于监控系统中。     

基于高层语义词袋的人体行为识别方法

人体行为分析为视频监控系统、视频检索系统提供重要的研究基础。本文提出了一种基于高层语义词袋模型 的人体行为识别方法。该方法根据底层词袋中词汇的相关关系,构造出一个基于词汇交互信息量的底层词汇图;然后使用层 次聚类的方法对该图进行分割,得到底层词汇组模型,最后将该模型表示为高层语义词袋模型。实验结果表明,该方法可以高 效地识别视频中的人体行为。     

基于神经网络的人体动作识别方法

人体动作识别一直是计算机视觉领域的研究重点。为了提高人体动作识别的准确度,本文提出一种基于神经网络的加权识别方法。首先利用ViBe算法提取人体运动前景,计算前景重心,然后将轮廓重心距作傅里叶变换获得傅里叶描述子,最后利用本文提出的基于神经网络的加权识别方法进行分类。实验结果表明,本文方法的识别率在89%以上。     

动态多视角复杂3D人体行为数据库及行为识别

提供了一个较大规模的基于RGB-D摄像机的人体复杂行为数据库DMV (Dynamic and multi-view) action3D,从2个固定视角和一台移动机器人动态视角录制人体行为。数据库现有31个不同的行为类,包括日常行为、交互行为和异常行为类等三大类动作,收集了超过620个行为视频约60万帧彩色图像和深度图像,为机器人寻找最佳视角提供了可供验证的数据库。为验证数据集的可靠性和实用性,本文采取4种方法进行人体行为识别,分别是基于关节点信息特征、基于卷积神经网络（Convolutional neural networks,CNN)和条件随机场(Conditional random field,CRF)结合的CRFasRNN方法提取的彩色图像HOG3D特征,然后采用支持向量机(Support vector machine,SVM)方法进行了人体行为识别;基于3维卷积网络（C3D）和3D密集连接残差网络提取时空特征,通过softmax层以预测动作标签。实验结果表明：DMV action3D人体行为数据库由于场景多变、动作复杂等特点,识别的难度也大幅增大。DMV action3D数据集对于研究真实环境下的人体行为具有较大的优势,为服务机器人识别真实环境下的人体行为提供了一个较佳的资源。     

基于MPEG-4的嵌入式IP网络监控摄像系统

基于MPEG4的嵌入式IP网络监控摄像系统是将智能摄像机与数字化和压缩芯片集成为一体的嵌入式视频采集及网络传输系统。采用了数字图像处理技术、MPEG-4数字音视频压缩技术、嵌入式操作系统及嵌入式操作系统软件开发技术、符合工业标准的应用接口开发技术、计算机网络通信技术等多种先进技术。     

Camera handoff with adaptive resource management for multi-camera multi-object tracking

Camera handoff is a crucial step to obtain a continuously tracked and consistently labeled trajectory of the object of interest in multi-camera surveillance systems. Most existing camera handoff algorithms concentrate on data association, namely consistent labeling, where images of the same object are identified across different cameras. However, there exist many unsolved questions in developing an efficient camera handoff algorithm. In this paper, we first design a trackability measure to quantitatively evaluate the effectiveness of object tracking so that camera handoff can be triggered timely and the camera to which the object of interest is transferred can be selected optimally. Three components are considered: resolution, distance to the edge of the camera’s field of view (FOV), and occlusion. In addition, most existing real-time object tracking systems see a decrease in the frame rate as the number of tracked objects increases. To address this issue, our handoff algorithm employs an adaptive resource management mechanism to dynamically allocate cameras’ resources to multiple objects with different priorities so that the required minimum frame rate is maintained. Experimental results illustrate that the proposed camera handoff algorithm can achieve a substantially improved overall tracking rate by 20% in comparison with the algorithm presented by Khan and Shah.     

人体行为识别数据集研究进展

人体行为识别是计算机视觉领域的一个研究热点,具有重要理论价值和现实意义.近年来,为了评价人体行为识别方法的性能,大量的公开数据集被创建.本文系统综述了人体行为识别公开数据集的发展与前瞻：首先,对公开数据集的层次与内容进行归纳.根据数据集的数据特点和获取方式的不同,将人体行为识别的公开数据集分成4类.其次,对4类数据集分别描述,并对相应数据集的最新识别率及其研究方法进行对比与分析.然后,通过比较各数据集的信息和特征,引导研究者选取合适的基准数据集来验证其算法的性能,促进人体行为识别技术的发展.最后,给出公开数据集未来发展的趋势与人体行为识别技术的展望.     

一种基于动态贝叶斯网络的人体动作识别方法

针对人体动作识别过程中存在的效率及准确率问题,提出了一种基于混合贝叶斯网络模型的人体动作识别方法。通过Kinect采集人体动作RGB-D信息,采用OpenNi提取关节点信息并计算躯干角度,使用后验概率动态调整SVM分类器和朴素贝叶斯分类器权重,能够识别多种不同动作,使两个分类器互为补充,增加识别率。最后通过与单分类器的对比试验,验证了该算法具有更高的效率和识别率。     

Human modeling and interaction in cyber-physical systems: A reference framework

This study focuses on the question of how humans can be inherently integrated into cyber-physical systems (CPS) to reinforce their involvement in the increasingly automated industrial processes. After a use-case oriented review of the related research literature, a human-integration framework and associated data models are presented as part of a multi-agent IoT middleware called CHARIOT. The framework enables human actors to be semantically represented and registered, together with other IoT entities, in a common service directory, thereby facilitating their inclusion in complex service chains. To validate and evaluate the proposed framework, a user study is conducted on a setup where a human and a robot arm collaborate on a “pick-assemble-place” job on a conveyor belt. Based on the human skill set parameters obtained from the user study, online and offline variants of task assignment on the conveyor belt setup are implemented and analyzed over the presented framework. The results illustrate possible efficiency gains through the consolidated online monitoring and control of all cyber-physical system entities, including human actors.     

基于可穿戴传感器的普适化人体活动识别

为了提高日常活动识别的准确性和自动化程度,减少人为干预,提出了利用可穿戴传感信号作为输入,通过深度神经网络进行人体活动识别的方法.首先,设计了普适环境下人体活动识别的系统架构,建立了一套加速度、生理信号等传感数据的采集系统;然后,对获取的传感数据进行降噪、加窗与归一化等预处理,并设计了长短时记忆递归神经网络来进行特征的自动提取和融合,从而实现活动识别.实验结果表明,该方法减少了对人工和专家知识的依赖,自动进行多模态传感器的融合,智能化程度高,分类效果好.     

土壤微量元素与人类活动强度的对应关系

本文以天津地区为例 ,在分析影响土壤中微量元素含量各种人为因素的基础上 ,利用天津地区人类活动强度对土壤微量元素含量变化的联系、不同土地利用方式土壤微量元素含量的变化规律 ,探讨土壤微量元素含量变化与人类活动强度之间的联系。研究发现 ,Hg、Cd、Se元素是最敏感的地球化学因子 ,能够反映天津地区土壤环境受人类活动的影响程度 ,利用土壤环境中Hg、Cd、Se的变化特征 ,可以确定本地区土壤环境受人类影响程度的大小     

Recognition of pedestrian trajectories and attributes with computer vision and deep learning techniques

Analyzing the walking behavior of the public is vital for revealing the need for infrastructure design in a local neighborhood, supporting human-centric urban area development. Traditional walking behavior analysis practices relying on manual on-street surveys to collect pedestrian flow data are labor-intensive and tedious. On the contrary, automated video analytics using surveillance cameras based on computer vision and deep learning techniques appears more effective in generating pedestrian flow statistics. Nevertheless, most existing methods of pedestrian tracking and attribute recognition suffer from several challenging conditions, such as inter-person occlusion and appearance variations, which leads to ambiguous identities and hence inaccurate pedestrian flow statistics.Therefore, this paper proposes a more robust methodology of pedestrian tracking and attribute recognition, facilitating the analysis of pedestrian walking behavior. Specific limitations of a current state-of-the-art method are inferred, based on which several improvement strategies are proposed: 1) incorporating high-level pedestrian attributes to enhance pedestrian tracking, 2) a similarity measure integrating multiple cues for identity matching, and 3) a probation mechanism for more robust identity matching. From our evaluation using two public benchmark datasets, the developed strategies notably enhance the robustness of pedestrian tracking against the challenging conditions mentioned above. Subsequently, the outputs of trajectories and attributes are aggregated into fine-grained pedestrian flow statistics among different pedestrian groups. Overall, our developed framework can support a more comprehensive and reliable decision-making for human-centric planning and design in different urban areas. The framework is also applicable to exploiting pedestrian movement patterns in different scenes for analyses such as urban walkability evaluation. Moreover, the developed mechanisms are generalizable to future researches as a baseline, which provides generic insights of how to fundamentally enhance pedestrian tracking.     

CNN多位置穿戴式传感器人体活动识别

随着人工智能的发展和可穿戴传感器设备的普及,基于传感器数据的人体活动识别（human activity recognition,简称HAR）得到了广泛关注,且具有巨大的应用价值.抽取良好判别力的特征,是提高HAR准确率的关键因素.利用卷积神经网络（convolutional neural networks,简称CNN）无需领域知识抽取原始数据良好特征的特点,针对现有基于传感器的HAR忽略三轴向传感器单一轴向多位置数据空间依赖性的不足,提出了两种动作图片构建方法T-2D和M-2D,构建多位置单轴传感器动作图片和非三轴传感器动作图片;进而提出了卷积网络模型T-2DCNN和M-2DCNN,抽取三组单一轴向动作图片的时空依赖性和非三轴传感器的时间依赖性,并将卷积得到的特征拼接为高层次特征用于分类;为了优化网络结构,减少卷积层训练参数数量,进一步提出了基于参数共享的卷积网络模型.在公开数据集上与现有的工作进行对比实验,默认参数情况下,该方法在公开数据集OPPORTUNITY和SKODA中F₁最大提升值分别为6.68%和1.09%;从传感器数量变化和单类识别准确性角度验证了模型的有效性;且基于共享参数模型,在保持识别效果的同时减少了训练参数.     

多层分类器模型的相似人体活动识别

针对基于单传感器活动识别中相似活动易混淆的问题,本文提出了一种基于广义判别分析的多层分类器融合的相似人体活动识别算法.首先提取基于单加速度计的多类活动数据的时域特征、频域特征以及时频特征,对不同特征进行特征分析与重要性评估以确定有效的特征维度.使用随机森林(RF,Random forest)算法对活动特征进行第1层分类...     

基于多目摄像机的鲁棒眼动跟踪技术研究

为改进单个远程传感器采集眼动数据时存在视场小、容易被遮挡物遮挡的缺点,研究了一种多目摄像机眼动跟踪技术,以更好地采集眼动数据。应用多个摄像机对人体头部姿态和眼球信息进行采集,通过分割视频帧提取瞳孔图像和计算被测用户头部姿态角度,将瞳孔图像放入卷积神经网络进行训练得到注视点坐标,并基于头部姿态信息计算每个摄像机的注视点权重,从而加权融合得到更精确的注视点信息。研究结果表明:在头部姿态角较大时,多目眼动追踪技术的精度比单目传感器的精度高30%~50%。该技术具有灵活性和通用性,在驾驶舱设计、用户用眼习惯评估和驾驶学员眼动绩效分析中具有重要的应用和推广价值。     

浅谈网络摄像机在污水处理厂中的应用

视频监控系统是污水处理厂一个重要的子系统,监视对象主要是工艺设施、重要设备、变电所和主要道路,对污水厂的运行、维护、安防有着重要的意义。本文对视频监控系统中的模拟摄像机和网络摄像机做了一个简单的对比,并对于网络摄像机应用于污水处理厂的合理性进行一定的探讨和研究。