基于形式概念分析和语义关联规则的目标图像标注

基于目标的图像标注一直是图像处理和计算机视觉领域中一个重要的研究问题.图像目标的多尺度性、多形变性使得图像标注十分困难.目标分割和目标识别是目标图像标注任务中两大关键问题.本文提出一种基于形式概念分析(Formal concept analysis, FCA)和语义关联规则的目标图像标注方法, 针对目标建议算法生成图像块中存在的高度重叠问题, 借鉴形式概念分析中概念格的思想, 按照图像块的共性将其归成几个图像簇挖掘图像类别模式, 利用类别概率分布判决和平坦度判决分别去除目标噪声块和背景噪声块, 最终得到目标语义簇; 针对语义目标判别问题, 首先对有效图像簇进行特征融合形成共性特征描述, 通过分类器进行类别判决, 生成初始目标图像标注, 然后利用图像语义标注词挖掘语义关联规则, 进行图像标注的语义补充, 以避免挖掘类别模式时丢失较小的语义目标.实验表明, 本文提出的图像标注算法既能保证语义标注的准确性, 又能保证语义标注的完整性, 具有较好的图像标注性能.     

基于均值漂移和边缘检测的轮廓跟踪算法

实时的轮廓跟踪算法可以为视频监控系统提供物体的轮廓信息以供对物体类别、物体行为等进行识别.提出一种基于均值漂移和边缘检测的轮廓跟踪算法.方法中,首先利用均值漂移算法跟踪得到目标物体的中心位置,同时用高斯统计模型进行背景更新,从前景图像和背景图像中分别得到具有相同位置和大小的前景矩形区域和背景矩形区域,然后用背景分割的方法得到目标物体区域,再对目标物体区域进行边缘检测就得到了目标物体的轮廓,进而实现了对目标物体的轮廓跟踪.实验表明,可以实时、准确、稳定地对目标物体进行轮廓跟踪.     

基于背景约束机制的目标识别方法及图像语义抽取

多数图像目标识别过程只对主要目标物进行提取,再分类识别,造成图像背景信息丢失,为此提出一种背景约束机制(background restraint mechanism)下的目标识别方法。通过视觉注意模型分别提取图像的前景目标物和背景信息,实现图像的前景目标物与背景分离,通过对背景图像信息的提取识别形成对前景目标物的概率约束。将此约束机制引入分类器中形成一种BRM_GAM(background-restraint-mechanism_Gaussian ARTMAP)分类模型,对前景目标物进行分类识别。实验结果表明,该方法有较好识别效率和时效性,符合人类认知。此外,提出一种利用GAM模型提取图像语义字典直方图,进行图像语义抽取的方法。     

基于肤色模型的人耳检测系统

人耳检测是人耳识别以及基于内容的图像和视频检索的一项重要任务。本文提出了一种将背景差分和肤色模型相结合的人耳检测算法。算法首先在序列图像中自动提取运动目标并进行人体检测,然后经过肤色分割进行人耳的粗定位,产生人耳候选区域。最后利用人耳检测模块判断候选区域中是否含有人耳,以及获得它们的位置、大小等信息。实验结果表明,该算法是有效的。     

基于Mobile U-Net的多目标(行人)检测算法

目标检测是指对图像或视频进行特征提取与分析,确定目标在图像中的位置信息,并能准确进行分类的一类算法。提出的Mobile U-Net是一种新型的无锚点的多目标检测算法,将语义分割问题转换成目标检测问题,并在分割网络U-Net网络的基础上,结合MobileNetV2,既保证了精度,又在满足了实时性。实采的视频数据上测试显示,在CPU i5-82501.8GHz硬件平台上的平均速度能达到17.38fps。     

基于肤色模型的人耳检测系统

人耳检测是人耳识别以及基于内容的图像和视频检索的一项重要任务.本文提出了一种将背景差分和肤色模型相结合的人耳检测算法.算法首先在序列图像中自动提取运动目标并进行人体检测,然后经过肤色分割进行人耳的粗定位,产生人耳候选区域.最后利用人耳检测模块判断候选区域中是否含有人耳,以及获得它们的位置、大小等信息.实验结果表明,该算法是有效的.     

基于神经网络的图像弱监督语义分割算法

类别激活热度图算法是一种可以在图像中找到具体分类对应的热度图的使用弱监督样本进行训练的算法,算法提取得到的语义信息可以提供给其他的检测任务或者定位任务所使用。提出一种使用神经网络进行计算的图像语义分割的算法,仅需要使用弱监督的训练数据对神经网络进行训练,得到模型。该算法将神经网络所输出的特征图像与网络参数相结合计算得到语义分割的大致区域,再在其中使用语义信息回传的方法,从大致区域的结果中得到更为精确的图像语义分割。最后介绍了该算法在不同的数据集上进行验证的结果,并且展示了内部的实现细节。     

激光雷达引导下的红外图像中行人检测

研究了一种利用激光雷达数据引导红外图像进行行人检测与识别的方法。首先针对激光雷达数据,提出了一种利用鲁棒主成分分析进行目标感兴趣区域检测的方法,进而设计了一种窗口滤波算法对前景矩阵进行滤波处理,得到目标感兴趣区域的位置信息。在此基础上,将该位置信息投影到红外图像中获取红外图像中的目标感兴趣区域,进而在红外图像感兴趣区域内利用稀疏编码金字塔算法和支持向量机完成行人识别。实验结果表明了该算法能够有效地完成行人识别。     

基于深度学习的遥感影像语义分割研究

高分辨率遥感图像的语义分割是遥感应用领域中的重要任务之一。针对经典语义分割网络在高分辨率遥感图像语义分割中存在边缘目标分割不准确、多尺度目标分割困难等问题，提出了一种基于改进空洞空间金字塔池的编码器-解码器结构网络(SMANet)。编码部分使用带有注意力机制的残差网络，使得网络充分提取图像的特征信息，其次通过多并行空洞空间金字塔模块（MASPP）获得特征图有关类别和空间上下文的更详细.信息；解码部分以自底向上方式将深层次语义信息逐步融入到低层次高分辨率图像中。使用WHDLD公开数据集对该算法进行实验，获得了6418%的平均交并比，实验结果表明SMANet优于目前主流的语义分割网络。     

基于LLC与加权SPM的车辆品牌型号识别

针对传统车辆识别算法鲁棒性及实时性不强的问题,结合局部线性约束编码(LLC)和加权空间金字塔匹配(SPM)模型,提出一种车辆品牌型号精细识别算法。提取图像方向梯度直方图特征,通过LLC对图像特征进行编码映射,得到具有语义信息的图像表达向量,以提高识别的准确率。利用加权SPM模型将空间位置信息引入图像表达向量中,并将每个图像的最终表达送入线性支持向量机分类器进行训练与识别。使用交通监控摄像头在不同天气和光照条件下采集150种车辆类型共56 827张图像进行实验,结果表明,该算法可有效改善识别效果,提高识别速度。     

A novel unsupervised 3D skeleton detection in RGB-D images for video surveillance

In this paper we present a novel moment-based skeleton detection for representing human objects in RGB-D videos with animated 3D skeletons. An object often consists of several parts, where each of them can be concisely represented with a skeleton. However, it remains as a challenge to detect the skeletons of individual objects in an image since it requires an effective part detector and a part merging algorithm to group parts into objects. In this paper, we present a novel fully unsupervised learning framework to detect the skeletons of human objects in a RGB-D video. The skeleton modeling algorithm uses a pipeline architecture which consists of a series of cascaded operations, i.e., symmetry patch detection, linear time search of symmetry patch pairs, part and symmetry detection, symmetry graph partitioning, and object segmentation. The properties of geometric moment-based functions for embedding symmetry features into centers of symmetry patches are also investigated in detail. As compared with the state-of-the-art deep learning approaches for skeleton detection, the proposed approach does not require tedious human labeling work on training images to locate the skeleton pixels and their associated scale information. Although our algorithm can detect parts and objects simultaneously, a pre-learned convolution neural network (CNN) can be used to locate the human object from each frame of the input video RGB-D video in order to achieve the goal of constructing real-time applications. This much reduces the complexity to detect the skeleton structure of individual human objects with our proposed method. Using the segmented human object skeleton model, a video surveillance application is constructed to verify the effectiveness of the approach. Experimental results show that the proposed method gives good performance in terms of detection and recognition using publicly available datasets.

     

一种有效的运动物体检测方法

为了从监控视频中检测出较高质量的运动物体,文章提出了一种基于帧间差分和背景差分相结合的运动目标的检测方法,并且采用像素级和帧级背景更新相配合的一种背景更新策略。算法求取各像素点处的最大概率灰度,从而提取出连续视频的背景图像;相邻帧则利用帧间差分法以及背景差分法得到两幅运动区域图像;将两幅运动区域图像相与,提取出较为准确的运动目标。实验证明,该算法对光线的变化鲁棒性较高,运算速度较快,且能够及时的响应监控视频的实时变化,提高运动目标的检测质量。     

Multi-object trajectory tracking

The majority of existing tracking algorithms are based on the maximum a posteriori solution of a probabilistic framework using a Hidden Markov Model, where the distribution of the object state at the current time instance is estimated based on current and previous observations. However, this approach is prone to errors caused by distractions such as occlusions, background clutters and multi-object confusions. In this paper, we propose a multiple object tracking algorithm that seeks the optimal state sequence that maximizes the joint multi-object state-observation probability. We call this algorithm trajectory tracking since it estimates the state sequence or “trajectory” instead of the current state. The algorithm is capable of tracking unknown time-varying number of multiple objects. We also introduce a novel observation model which is composed of the original image, the foreground mask given by background subtraction and the object detection map generated by an object detector. The image provides the object appearance information. The foreground mask enables the likelihood computation to consider the multi-object configuration in its entirety. The detection map consists of pixel-wise object detection scores, which drives the tracking algorithm to perform joint inference on both the number of objects and their configurations efficiently. The proposed algorithm has been implemented and tested extensively in a complete CCTV video surveillance system to monitor entries and detect tailgating and piggy-backing violations at access points for over six months. The system achieved 98.3% precision in event classification. The violation detection rate is 90.4% and the detection precision is 85.2%. The results clearly demonstrate the advantages of the proposed detection based trajectory tracking framework.     

基于帧间差分法的动体特征速度聚类分析

针对智能视频监控中快速、准确的检测和识别运动物体的问题,提出了一种依据运动物体特征速度来检测识别动体以及解读其语义含义的算法。该方法以相对帧间差分法为基础,通过对预处理后的二值斑块图像的标记,计算斑块的像素长度作为其特征速度,并依据斑块特征速度的众数进行聚类分析,从斑块特征速度得到运动物体的特征速度语义解读和运动物体的检测识别。实验结果表明,斑块的特征速度不仅可以实现对运动物体的检测,而且通过聚类分析可以准确的得出动体特征的语义解读。用特征速度和众数聚类分析方法实现对运动物体的检测识别和语义解读相对于其他统计算法简单有效,便于智能摄像机的嵌入式开发。     

一种基于梯度方向信息的运动目标检测算法

运动目标检测是智能视觉监控系统的基本内容。在对现有算法分析的基础上提出了一种基于梯度方向信息的运动目标检测算法。首先利用方向信息提取视频图像序列中每一帧的边缘梯度图,然后通过改进传统帧差算法,采用uint8数据格式处理含有时间关系的两帧图像以此确定运动目标粗略边界,经运动目标连通域识别,最后结合梯度方向信息准确提取运动目标的完整轮廓。实验结果表明,该算法克服了传统帧差算法不能准确定位目标的缺点,在室内外复杂背景下均能准确地提取完整的目标轮廓。     

基于帧间差分和边缘差分的遗留物检测算法

遗留物检测是智能视频监控系统的核心功能,遗留物一般较小,所处环境复杂,传统的运动目标检测算法直接用于遗留物检测效果一般.提出了一种基于帧间差分与边缘差分的遗留物检测算法,首先进行帧间差分得到运动目标区域,然后将当前帧图像和前一帧的背景图像进行边缘差分运算得到运动目标的边缘,融合二次差分的结果即可得到运动目标的完整轮廓特征,最终通过判断运动目标在场景中的滞留时间是否达到或超过报警系统设置的阈值来标示遗留物,供智能视频监控系统处理.实验结果证明该算法实时性好且识别率较高.     

Multiresolution video object extraction fitted to scalable wavelet-based object coding

To enable content based functionalities in video processing algorithms, decomposition of scenes into semantic objects is necessary. A semi-automatic Markov random field based multiresolution algorithm is presented for video object extraction in a complex scene. In the first frame, spatial segmentation and user intervention determine objects of interest. The specified objects are subsequently tracked in successive frames and newly appeared objects/regions are also detected. The video object extraction algorithm includes discrete wavelet transform decomposition multiresolution Markov random field (MRF)-based spatial segmentation with emphasis on border smoothness at different resolutions, and an MRF-based backward region classification that determines the tracked objects in the scene. Finally, a motion constraint, embedded in the region classifier, determines the newly appeared objects/regions and completes the proposed algorithm towards an efficient video segmentation algorithm. The results are applicable for generic segmentation applications, however the proposed multiresolution video segmentation algorithm supports scalable object-based wavelet coding in particular. Moreover, compared to traditional object extraction algorithms, it produces smoother and more visually pleasing shape masks at different resolutions. The proposed effective multiresolution video object extraction method allows for larger motion, better noise tolerance and less computational complexity     

A novel framework for intelligent surveillance system based on abnormal human activity detection in academic environments

Abnormal activity detection plays a crucial role in surveillance applications, and a surveillance system that can perform robustly in an academic environment has become an urgent need. In this paper, we propose a novel framework for an automatic real-time video-based surveillance system which can simultaneously perform the tracking, semantic scene learning, and abnormality detection in an academic environment. To develop our system, we have divided the work into three phases: preprocessing phase, abnormal human activity detection phase, and content-based image retrieval phase. For motion object detection, we used the temporal-differencing algorithm and then located the motions region using the Gaussian function. Furthermore, the shape model based on OMEGA equation was used as a filter for the detected objects (i.e., human and non-human). For object activities analysis, we evaluated and analyzed the human activities of the detected objects. We classified the human activities into two groups: normal activities and abnormal activities based on the support vector machine. The machine then provides an automatic warning in case of abnormal human activities. It also embeds a method to retrieve the detected object from the database for object recognition and identification using content-based image retrieval. Finally, a software-based simulation using MATLAB was performed and the results of the conducted experiments showed an excellent surveillance system that can simultaneously perform the tracking, semantic scene learning, and abnormality detection in an academic environment with no human intervention.

     

基于实例分割模型优化的道路抛洒物检测算法

在交通安全领域,道路抛洒物易引发交通事故,构成了交通安全隐患。针对传统抛洒物检测方式识别率低、对于多类抛洒物检测效果不佳等问题,提出了一种基于实例分割模型CenterMask优化的道路抛洒物检测算法。首先,使用空洞卷积优化的残差网络ResNet50作为主干神经网络来提取特征并进行多尺度处理;然后,通过距离交并比（DIoU）函数优化的全卷积单阶段（FCOS）目标检测器实现对抛洒物的检测和分类;最后,使用空间注意力引导掩膜作为掩膜分割分支来实现对于目标形态的分割,并采用迁移学习的方式实现模型的训练。实验结果表明,所提算法对于抛洒物目标的检测率为94.82%,相较常见实例分割算法Mask R-CNN,所提的道路抛洒物检测算法在边界框检测上的平均精度（AP）提高了8.10个百分点。     

视频监控中一种完整提取运动目标的检测算法

提出一种视频监控中完整、精确提取运动目标前景的检测算法.首先对彩色图像建立混合高斯模型,由背景差分法得到基本准确的前景图像;然后和对称差分法图像综合,得到完整可靠的运动目标图像;再利用亮度信息消除运动目标阴影;最后利用形态学滤波和连通区域面积检测进行后处理.实验结果表明,该算法检测的运动目标前景信息完整准确,对固定场景下的视频监控系统具有一定实用价值.