老年人异常行走步态特征提取

计算机视觉的步态分析主要用于实现人体的身份识别,而通过异常步态分析来识别老年人异常状况方面的研究却很少.为对老人异常步态进行识别,提出了一种新的步态特征提取的方法,主要用于老年人异常行走步态特征的提取.使用运动历史图像进行图像序列的表示,并且从中提取出Zernike矩特征用来反应步态的特征向量.同时为了保证获取的特征量的充分性与有效性,更完备地描述人体行为序列,利用信息论中的互信息来确定分类时采用的Zernike矩的最高阶次,并进行仿真.实验结果表明,利用提出的方法进行特征提取,在老年人异常行走步态特征提取中取得了很好的效果.     

步态识别问题的特点及研究现状

步态识别作为一种较新的生物认证技术有其独特优势,在计算机视觉研究领域又是一个难题.本文首先分析了步态识别问题的这两个特点.其次,按一个模式识别系统所涉及的4个问题域：传感器的选择、预处理技术、表达方法、决策模型为索引去分析步态识别问题.在表达方法一节中将文献中所反映的研究方法从计算机视觉的角度分为基于模型和基于整体的两大类,并对每类方法进行了举例说明,指出了所举出的方法的优缺点和其提取步态模式中的结构成分信息和运动特征信息时所采用的方法.再次,对步态识别算法性能评价标准和可得到的数据库进行了分析说明.最后得出了目前步态识别问题研究中的几个薄弱点,指出进一步研究此问题的发展空间.     

一种改进的步态识别方法

步态识别通过人体走路的姿势来识别人的身份。近年来,步态作为一种生物特征识别技术备受计算机视觉研究者的关注。对某个人的一个步态序列利用动态Viterbi算法得到一个样本姿态序列,对其多个步态样本姿态序列的对应姿态取平均得到这个人的特征姿态序列,对特征姿态采用主成分分析法和线性判别分析法处理特征空间,并用最近邻法进行识别。利用CASIA数据库对本文方法进行验证,取得了较高的识别率,并对体形变化具有较强的鲁棒性。     

基于步态触觉信息的图书馆智能机器人异常状态检测系统

针对当前图书馆智能机器人步态识别准确率低,导致异常状态检测效果差的问题,提出基于步态触觉信息的图书馆智能机器人异常状态检测和分类。采用基于局部空间信息加权的K-means算法对静态步态图像进行分割处理,分别构建基于改进K-means的CNN网络模型和基于时域注意力的3D残差网络模型,通过这两个模型对静态、动态步态进行特征提取和识别。实验结果表明,对比于SVM分类器,改进K-means算法的CNN网络模型静态步态识别准确率高达98.7%;3D-CNN模型的动态步态分类准确率为99.72%,均高于其他分类模型。最后结合两种算法进行异常状态检测发现,本算法的分类准确率、敏感度和特异性分别为95.42%、95.53%、94.37%。综合分析可知,提出的算法能够实现静态动态的准确识别和异常状态检测,具有一定有效性。     

基于SVM的偏瘫患者异常步态识别与临床康复辅助诊断系统

针对脑卒中偏瘫患者的异常步态识别与评估的问题，提出一种基于支持向量机(SVM)的步态分类方法，依据患者下肢行走过程中的连续运动数据对异常步态的细节特征描述，对偏瘫步态进行细分，辅助临床医师对脑卒中患者肢体运动功能异常进行诊断及康复疗效评定。构建穿戴式步态时空参数检测及虚拟现实康复训练系统，提出基于下肢关节角度信息的特征提取方法，建立运动信号与偏瘫步态间的映射关系。基于偏瘫患者在康复治疗中的临床实时步态时空数据，通过对比多种机器学习方法，采用多项式核函数的支持向量机的决策融合模型获得了90%异常步态识别平均准确率，在区分正常与异常步态的基础上，进一步验证了对划圈步态和膝过伸步态的正确诊断。     

应用柔性传感器的人体步态识别系统

步态识别作为一种新的生物特征识别技术，主要用于行走功能评定、矫治异常步态、或康复器具性能的评价等方面。文章介绍了一种新型的用于步态识别的数据衣，这种数据衣使用新型的柔性传感器，有效地利用了腿部关节的角度信息。具有价格便宜、识别精确度高等优点。将这种数据衣应用于步态识别系统，与视觉部分相结合，可以更准确地识别步态信息。     

基于拓扑非线性动态建模的神经退行性疾病异常步态识别

通过对步态节律变化的观察,可以实现对人体复杂系统的观测,在行走过程中,步幅间隔时间序列的动态特性,能有效反映人体系统的状态变化,可用于步态异常检测及相关疾病辨识。人体步态传感信息的时间序列相空间重建,是一种有效表征系统非线性动力学特性的建模方法。相空间的几何建模和统计分析,是异常步态识别典型的分析方法,被广泛应用于神经退行性疾病检测等临床研究中。该文从空间拓扑特性分析的角度出发,提出一种基于拓扑非线性动态建模的分析方法,用于神经退行性疾病的异常步态识别。该文首先采用延时嵌入的相空间重构方法,将步态的波动时间序列转化为抽象相空间的状态点云;其次,采用基于计算拓扑中的持续同调工具,提取状态点云所在空间的拓扑描述信息;再次,采用基于拓扑描述的持续态势图,构建时间序列的拓扑非线性动态特征;最后,融合步态周期中左右足的步幅间隔、站立间隔、摆动间隔时间序列的拓扑非线性动态特征,作为分类器输入,构建出异常步态的机器学习识别模型。对患有肌硬化症、亨廷顿病和帕金森病的神经退行性疾病患者,进行 5 min 异常步态的连续行走数据(50 步滑动窗数据)测试,步态识别的准确率分别为 0.875 0(0.914 6)、0.940 6(0.962 3) 和 0.958 3(0.961 4)。因此,拓扑非线性动态建模分析是一种有效的神经退行性疾病异常步态检测方法,为基于步态分析的神经退行性疾病检测和可穿戴数据分析提供了一种新的思路。     

步态识别综述

步态识别作为一种新的生物认证技术,通过人的行走方式识别个体的身份。本文首先分析了步态识别的特点及其研究背景;其次,对目前步态识别中涉及到的几项关键技术所采用的方法进行了简单的描述及分类,并分析各种技术的主要优缺点,最后,提出了目前步态识别问题研究中的几个薄弱点,指出进一步研究发展空间。     

基于SVM的步态识别方法综述

步态识别是非接触式生物特征识别领域的前沿课题,通过对人体行走方式的识别以确定个体的身份,在智能视频监控领域有较高的研究价值.步态分类是步态识别过程中的重要任务和关键步骤.首先概述了步态识别过程及分类方法,然后重点对基于支持向量机的步态分类方法进行了综述,分析了基于该方法的最新研究进展,对每个具体研究方法的优缺点进行了对比.最后,指出目前步态识别在实际应用中存在的局限性,并对该领域发展方向进行了展望.     

视觉手势识别综述

随着计算机视觉的发展和人机交互的需要,手势识别研究取得了蓬勃的发展。然而,很少有对手势识别进行全面分析、总结、评述的相关综述研究。 针对这一问题, 就基于计算机视觉的手势识别技术的发展现状展开综述, 系统地分析和梳理了近三十年来基于计算机视觉的手势识别技术,按照手势识别的流程,将手势识别分为检测分割、分析和识别3个主要步骤,并对每个步骤分别进行评述,总结归纳其适用范围及优缺点。最后对手势识别进行总结展望。     

步态识别研究进展

近年来步态识别技术已经成为生物特征识别领域一个新的研究热点。该技术是唯一可在远距离非接触状态下识别生物特征的技术,因此引起了各国学术科研机构的重视。对步态识别系统的一般处理过程进行了综述,重点分析和跟踪了步态特征提取技术的最新研究进展,讨论了各种方法中典型技术的优缺点和步态识别技术所面临的挑战,并概括介绍了常用的步态评测数据库和实验结果,最后展望了步态识别技术未来的发展方向和趋势。     

A new gait recognition system based on hierarchical fair competition-based parallel genetic algorithm and selective neural network ensemble

The recognition of a person from his or her gait has been a recent focus in computer vision because of its unique advantages such as being non-invasive and human friendly. However, gait recognition is not as reliable an identifier as other biometrics. In this paper, we applied a hierarchical fair competition-based parallel genetic algorithm and a neural network ensemble to the gait recognition problem. A diverse set of potential neural networks are generated to increase the reliability of the gait recognition, not only the best ones. Furthermore, a set of component neural networks is selected to build a gait recognition system such that generalization errors are minimized and negative correlation is maximized. Experiments are carried out with the NLPR and SOTON gait databases and the effectiveness of the proposed method for gait recognition is demonstrated and compared to previous methods.     

Silhouette analysis-based gait recognition for human identification

Human identification at a distance has recently gained growing interest from computer vision researchers. Gait recognition aims essentially to address this problem by identifying people based on the way they walk. In this paper, a simple but efficient gait recognition algorithm using spatial-temporal silhouette analysis is proposed. For each image sequence, a background subtraction algorithm and a simple correspondence procedure are first used to segment and track the moving silhouettes of a walking figure. Then, eigenspace transformation based on principal component analysis (PCA) is applied to time-varying distance signals derived from a sequence of silhouette images to reduce the dimensionality of the input feature space. Supervised pattern classification techniques are finally performed in the lower-dimensional eigenspace for recognition. This method implicitly captures the structural and transitional characteristics of gait. Extensive experimental results on outdoor image sequences demonstrate that the proposed algorithm has an encouraging recognition performance with relatively low computational cost.     

Multi-gait recognition using hypergraph partition

Gait recognition is a challenging problem in computer vision, especially when multi-persons walk together, called as multi-gait recognition. Multi-gait recognition includes two aspects: participant segmentation and participant recognition. In this paper, we propose to segment each participant by hypergraph partition and recognize each participant by multi-linear canonical correlation analysis algorithm (UMCCA). Firstly, raw pixel areas are obtained by grid, and each pixel area is taken as a hypergraph vertex. Then HOG-based detection and tracking technology is used to calculate the weight of each hyperedge. After segmentation, UMCCA is used to extract gait features. Finally, identity of multi-gait is recognized. The experimental results demonstrate that our proposed method achieves good performance on multi-gait dataset.     

MPCA: Multilinear Principal Component Analysis of Tensor Objects

This paper introduces a multilinear principal component analysis (MPCA) framework for tensor object feature extraction. Objects of interest in many computer vision and pattern recognition applications, such as 2-D/3-D images and video sequences are naturally described as tensors or multilinear arrays. The proposed framework performs feature extraction by determining a multilinear projection that captures most of the original tensorial input variation. The solution is iterative in nature and it proceeds by decomposing the original problem to a series of multiple projection subproblems. As part of this work, methods for subspace dimensionality determination are proposed and analyzed. It is shown that the MPCA framework discussed in this work supplants existing heterogeneous solutions such as the classical principal component analysis (PCA) and its 2-D variant (2-D PCA). Finally, a tensor object recognition system is proposed with the introduction of a discriminative tensor feature selection mechanism and a novel classification strategy, and applied to the problem of gait recognition. Results presented here indicate MPCA's utility as a feature extraction tool. It is shown that even without a fully optimized design, an MPCA-based gait recognition module achieves highly competitive performance and compares favorably to the state-of-the-art gait recognizers.     

Automatic detection of abnormal gait

Analysing human gait has found considerable interest in recent computer vision research. So far, however, contributions to this topic exclusively dealt with the tasks of person identification or activity recognition. In this paper, we consider a different application for gait analysis and examine its use as a means of deducing the physical well-being of people. Understanding the detection of unusual movement patterns as a two-class problem suggests using support vector machines for classification. We present a homeomorphisms between 2D lattices and binary shapes that provides a robust vector space embedding of segmented body silhouettes. Experimental results demonstrate that feature vectors obtained from this scheme are well suited to detect abnormal gait. Wavering, faltering, and falling can be detected reliably across individuals without tracking or recognising limbs or body parts.     

基于多区域分割的步态表示与识别算法研究

提出了一种基于多区域分割的步态表示方法,将视频中的目标人体区域部分按人体结构特点划分为多个子区,每个子区通过连接人体重心的椭圆进行拟和,建立多连接椭圆的人体结构模型,预处理阶段引入一个归一化过程以实现对各种视角下的步态序列进行表示.识别过程将模型参数作为步态特征,并引入了一定的融合机制对特征进行选择和融合.实验表明,该算法对于多个视角下的步态序列均具有较好的识别性能.     

基于步态的身份识别技术

随着信息社会对安全的要求不断提高,利用生物特征进行快速准确的身份识别成了当今的主流。与传统的身份鉴定手段相比,生物特征识别具有无可比拟的优势,特别是步态识别技术,由于其对系统分辨率要求低、远距离识别、非侵犯性和难以隐藏等特点而倍受计算机视觉研究者的关注。对步态识别所涉及的运动检测与跟踪、特征提取、特征处理以及模式识别分别进行了详细论述。