数字视频监控系统中实时运动检测系统的研究

在数字视频监控系统中,从视频流里捕获出序列图像并进行实时运动检测是一项重要的功能。采用两个进程分别实现视频图像的捕获和运动检测,命名管道作为两个进程之间数据通信的桥梁。提出了一种基于帧差交集快速视频分割法、阈值面积算法结合数学形态学运算提取运动目标区域的数字图像处理算法,然后再进行运动目标的跟踪定位,实现实时运动检测。     

Detection of swimmer using dense optical flow motion map and intensity information

A vision-based system that can locate individual swimmers and recognize the activities is applicable for swimming gait analysis, drowning event detection, etc. The system relies on accurate detection of swimmer’s body parts such as head and upper limbs. The swimmer detection problem can be regarded as background subtraction. Swimmer detection in the aquatic environment is very difficult due to a dynamic background with water ripples, splashes, specular reflections, etc. This paper presents a swimmer detection method which utilizes both local motion and intensity information estimated from the image sequence. Local motion information is obtained by computing dense optical flow and periodogram. We adopt a heuristic approach to generate a motion map characterizing the local motions (random/stationary, ripple or swimming) of image pixels over a short duration. Intensity information is modeled as a mixture of Gaussians. Finally, using the motion map and the Gaussian models, swimmers are detected in each video frame. We test the method on video sequences captured at daytime, and nighttime, and of different swimming styles (breaststroke, freestyle, backstroke). Our method can detect swimmers much better than that using intensity information alone. In addition, we compare our method with existing algorithms—codebook model and self-organizing artificial neural networks. The methods are tested on publicly available video sequence and our swimming video sequence. We show through the quantitative measures the superiority of our method.     

基于累积量和主运动方向的视频烟雾检测方法

视频烟雾检测具有响应速度快、非接触等优点。但现有的视频检测方法误报率比较高。通过分析早期火灾烟雾运动规律,提出了一种适用于普通视频的烟雾检测方法。为了加快检测速度,将视频图像分割成大小相等的块,并估计每个块的运动方向。采用滑动时间窗口生成块运动方向时间序列,在此时间序列的基础上计算块的累积量和主运动方向。累积量可以反映出运动持续的程度,而主运动方向表明每个块最可能的运动方向,可以有效地抑制噪声的干扰。根据累积量和主运动方向提取出3维特征矢量,采用贝叶斯分类器进行烟雾的检测。实验结果表明,该方法鲁棒性高、速度快,能够准确地检测烟雾的出现。     

抗相机运动干扰的欧拉视频振动检测

相机运动的干扰是造成视频振动检测误差的重要原因。针对该问题,提出一种互抑制一致采样方法,对视频中的振动信号和相机运动信号实现有效分离,从而提高视频振动检测的可靠性。通过SURF（加速稳健特征）算法提取候选的特征点,并设计了振动与相机运动的互抑制测度,对候选的特征点进行分离,以获得相机运动的特征点。根据相机运动特征点对视频图像进行配准,以获得去除相机运动干扰的视频序列。对稳定相机的视频序列,采用欧拉视频振动检测方法获得振动频率。自行采集了不同相机运动下的视频,并针对互抑制测度的参数进行估计。通过对测试集数据进行验证,得到的振动频率准确率优于现有的非接触振动检测方法。     

融合非局部神经网络的行为检测模型

针对在视频行为检测中卷积神经网络(CNN)对时域信息理解能力不足的问题,提出了一种融合非局部神经网络的行为检测模型.模型采用一种双分支的CNN结构,分别提取视频的空间特征和运动特征.将视频单帧和视频连续帧序列作为网络输入,空间网络对视频当前帧进行2D CNN特征提取,时空网络采用融合非局部模块的3D CNN来捕获视频帧...     

协同运动状态估计的多目标跟踪算法

多目标跟踪在视频分析场景中有着广泛的应用,如人机交互、虚拟现实、自动驾驶、视频监控和机器人导航等。多目标跟踪问题可以表示为在已有的检测数据上进行目标轨迹关联,检测算法的准确性对跟踪性能起着关键性的作用。在基于检测的目标跟踪框架中,提出了一种协同运动状态估计的跟踪算法,该算法主要关注相邻帧之间的数据关联,从目标检测、目标运动状态估计和数据关联这3个方面来直接解决多目标跟踪面临的挑战。首先,对于目标检测,采用Multi Scale Convolutional Neural Network(MS-CNN)算法作为检测器,这是因为深度学习在检测的效益上优于传统的机器学习方法;其次,为了更好地预测目标的运动状态和处理目标间的遮挡,针对不同状态的目标采取不同的运动估计方法: 采用核相关滤波来评估处于跟踪状态的目标的运动状态,当目标处于遮挡状态时,采用卡尔曼滤波做运动估计;最后,采用Kuhn-Munkres算法对检测目标和跟踪轨迹做数据关联。通过大量的实验证实了算法的有效性,且实验结果表明算法的准确性很高。     

Motion detection and object tracking with discrete leaky integrate-and-fire neurons

A biologically inspired visual system capable of motion detection and pursuit motion is implemented using a Discrete Leaky Integrate-and-Fire (DLIF) neuron model. The system consists of a visual world, a virtual retina, the neural network circuitry (DLIF) to process the information, and a set of virtual eye muscles that serve to move the input area (visual field) of the retina within the visual world. Temporal aspects of the DLIF model are heavily exploited including: spike propagation latency, relative spike timing, and leaky potential integration. A novel technique for motion detection is employed utilizing coincidence detection aspects of the DLIF and relative spike timing. The system as a whole encodes information using relative spike timing of individual action potentials as well as rate coded spike trains. Experimental results are presented in which the motion of objects is detected and tracked in real and animated video. Pursuit motion is successful using linear and also sinusoidal paths which include object velocity changes. The visual system exhibits dynamic overshoot correction heavily exploiting neural network characteristics. System performance is within the bounds of real-time applications.     

基于视皮层V1模型的随机点视频序列运动特征提取

针对复杂场景中视频序列目标运动特征提取困难的问题,借鉴生物视觉系统对视频动态目标的运动感知机制,改进初级视皮层(V1)细胞模型,提出一种基于生物视皮层机制的视频运动特征提取方法。采用时空滤波器与半平方加归一化分别模拟神经元感受野的线性与非线性特性,再通过在输出权值中加入方向选择性调节参数得到普适性的V1细胞模型,从而解决传统模型方向选择性单一、多方向选择能力偏弱的问题。仿真结果表明所提模型模拟输出与生物实验数据较为吻合,能够模拟不同方向选择性的V1细胞,对复杂运动形态的随机点视频序列具有良好的运动特征提取能力。依靠该方法可以为处理特征光流信息提供新的思路,进而实现对视频序列目标的运动特征提取和有效跟踪。     

X射线探测用SSPA器件的数据采集系统

设计了一种供Ｘ射线ＳＳＰＡ（Ｓｅｌｆ ｓｃａｎｎｅｄ ｐｈｏｔｏｄｉｏｄｅ ａｒｒａｙ）器件使用的８位高速数据采集系统。Ｘ射线ＳＳＰＡ的视频信号是窄脉冲,所以必须采用峰值保持,同时为了在同一系统中测量多路信号,设计了一多路开关。在使用Ｘ射线ＳＳＰＡ器件时需对视频信号进行逐位高速采集,因此所有视频信号在一次逐位转 换完毕,存储在帧存储器中,然后再逐位读出。所以本系统主要包括多通道开关、峰值保持、高速     

Dust particle detection in traffic surveillance video using motion singularity analysis

Dust particle detection in video aims to automatically determine whether the video is degraded by dust particle or not. Dust particles are usually stuck on the camera lends and typically temporally static in the images of a video sequence captured from a dynamic scene. The moving objects in the scene can be occluded by the dusts; consequently, the motion information of moving objects tends to yield singularity. Motivated by this, a dust detection approach is proposed in this paper by exploiting motion singularity analysis in the video. First, the optical model of dust particle is theoretically studied in by simulating optical density of artifacts produced by dust particles. Then, the optical flow is exploited to perform motion singularity analysis for blind dust detection in the video without the need for ground truth dust-free video. More specifically, a singularity model of optical flow is proposed in this paper using the direction of the motion flow field, instead of the amplitude of the motion flow field. The proposed motion singularity model is further incorporated into a temporal voting mechanism to develop an automatic dust particle detection in the video. Experiments are conducted using both artificially-simulated dust-degraded video and real-world dust-degraded video to demonstrate that the proposed approach outperforms conventional approaches to achieve more accurate dust detection.     

基于运动矢量的摄像机运动定性分类方法

在视频序列中,摄像机运动在某种程序上反映了当前视频的语分语义信息,知道了摄像机运动将能够取更好的实现对视频的游览以及检索,针对现有的依据光流分布来摄像机运动参数算法中的不足,给出了一种定性分析相机运动的方法,该方法能够在相机聚焦中心－ＦＯＥ（focus-of-expansion)不在成像平面中心时检测出给定类型的摄像机运动,实验结果表明该方法对于从视频序列中分析出给定类型的摄像机运动具有较的效果。     

基于动目标检测的视频监控智能节点设计

针对现有视频监控系统无效信息多造成存储资源严重浪费的现象,提出了基于动目标检测的视频监控智能节点设计方案;利用微波移动传感器检测运动目标多普勒信号,通过微控器采集调理后的多普勒信号完成运动目标识别,并控制传输设备将含有动目标的视频监控信息和多普勒频率数据传输到监控中心进行实时处理;实验结果表明,视频监控智能节点最大探测距离可达15m,该设计有效提高了视频监控的有效信息,减少了存储资源,具有广泛的应用前景。     

视频监控中人的运动检测方法研究与实现

为了提高视频监控的实时性、准确性和可靠性,引入运动目标检测非常必要,而在此基础上的人运动检测更是后续各种高级处理的基础。根据视频监控的特点,采用一种基于自适应背景图像估计与当前多帧图像的混合差的算法来实现快速精确地检测和提取运动目标区域,并充分利用视频图像的时域连续特性和人脸肤色信息,实现快速可靠的人脸定位,从而准确定位人运动区域。实验表明,该算法对人的运动检测在光线、姿势变化等情况下具有良好的鲁棒性,适于实时监控系统的应用。     

Models for Image Interpolation Based on the Optical Flow

Optical flow is the 2D motion that needs to be recovered from a video sequence. In this paper we study variational principles for the generation of interpolating sequences between two images. The basic assumption is that there exists an underlying video sequence that solves the optic flow equation and interpolates the two images. The numerical solution of the interpolation problem is reduced to the solution of a system of coupled partial differential equations. Some numerical simulations are presented. Received June 29, 2000; revised November 29, 2000     

基于运动筛选和3D卷积的视频早期烟雾检测

To solve the problem of high false alarm and high missed detection in the complex environment of early smoke detection based on video, a method based on motion extraction of suspected areas is proposed and a multi-scale 3D convolutional neural network with input of 6 frames（6M3DC） is designed for video smoke detection. Firstly, the motion regions are obtained through the background difference model after average filtering and the positions of the block in which the motion regions are located are calculated, and then the motion blocks are extracted by color judgment and mean HASH algorithm and the nonconforming blocks are updated to the background image. Finally, by combining the suspected blocks of the same region of 6 consecutive frames as the input for the 3D convolutional neural network for detection, blocks detected as smoke are marked and non-smoke blocks are updated to the background image. The experimental results show that the algorithm is adaptive to slow moving smoke and can detect smoke in complex environment.     

基于音频分析的视频场景检测

目前场景检测的研究,主要是基于图像和视频。但音频同样具有丰富的场景信息,基于音频分析的计算量是比较少的,对自动或者半自动的场景检测,基于音频分析的方法也是更为让用户接受的。可以把基于音频分析的方法作为视频场景检测的辅助手段,以获得更为准确的场景检测和分割。该文提出了一个基于内容的音频分析系统,对视频序列实现基于音频分析的场景检测和分割。该系统能有效的解决许多诸如图像变化了,而实际场景并未变化的情形。且本系统整体运算复杂度较基于视频／图像的场景检测与分割系统要低。     

室内人体运动目标的自动跟踪方法

针对人体运动目标的自动实时跟踪,设计一种新的基于P89v51内核的运动摄像头云台控制系统.对人体运动的图像检测与跟踪,提出一种快速的模板匹配方法.用改进Surendra算法自适应地获取背景图像以提取匹配模板,通过摄像头运动前后帧相同的运动区域来缩小匹配区域,进行快速目标匹配,达到实时性要求.该系统已应用在视频教学及会议中,实现自动人体运动目标跟踪与摄像.     

模拟初级视皮层注意机制的运动对象检測模型

视频监控的广泛应用使运动对象检测成为研究热点,但运动的不确定性增加了检测难度。鉴于人类视觉系统能高效地感知运动对象,研究者从神经生理学和心理学的角度提出了运动检测的生物学模型。根据上述研究成果,提出模拟初级视皮层的运动对象检测模型。使用三维Gabor时空滤波器模拟人类初级视皮层中简单细胞的经典感受野,通过非线性组合获取复杂细胞对运动对象刺激响应的运动能量,应用细胞的中心环绕作用及相关性运动检测增强运动信息并抑制环境干扰,采用信息融合获取运动对象的显著性图,并利用WTA神经网络模型实现对运动H标的感知。实验结果表明,该模型能有效检测到视频中的运动目标,运算速度较其他仿视神经加工的视觉注意模型更快。     

视频监控系统中运动检测算法的研究

运动检测是现代视频监控系统的核心.在分析和探讨了几种运动检测算法后,提出了一种新的应用于视频监控系统的运动检测算法,该算法结合统计法和边缘检测筛选出运动边缘点,对运动边缘点逐个进行块匹配最优搜索,估算出运动矢量.该算法的应用有效地压缩了存储的视频数据,改善了系统性能,有很好的实用价值.     

Head pose estimation in solving human-computer interaction problems

A system that estimates a user’s head pose by its video image is described. The system includes three basic algorithms, that is, segmentation, landmark detection, and motion direction estimation. The dynamics of change in geometric relations between facial landmarks on a sequence of frames is used to determine the direction of head motion. The change in the angle between the lines that connect the corners of the eyes and the tip of nose is shown to be similar to the yaw angle in their dynamics of change. The described system operates in real time (7 frames per second) and ensures a high precision estimate of motion direction (p = 0.95).