【作者】 蔡婷；

【导师】 李鸿；

【作者基本信息】 长沙理工大学 ， 交通信息工程及控制， 2012， 硕士

【摘要】 急剧增长的机动车保有量与十分有限的路网容量之间的严重不平衡，造成了如今全世界范围内各大城市普遍可见的城市交通拥挤现象。许多实践证明，单独从交通需求或供给上试图解决交通拥挤都是很难奏效的，而且我国很多城市也面临着无地可用来新建道路设施的尴尬。此时，交通管理就显得尤为重要，完善的管理能最大限度的发挥出路网的容量，反之则会降低路网容量。近些年来，一种智能且高效的交通管理手段正应运而生----智能交通系统。IntelligentTransportation System，简称ITS。智能交通系统是将先进的信息技术、通讯技术、传感技术、控制技术以及计算机技术等有效地集成运用于整个交通运输管理体系，而建立起的一种在大范围内、全方位发挥作用的，实时、准确、高效的综合运输和管理系统。许多发达国家和地区早就已经开始了对智能交通系统的研究和使用，我国近些年来也逐渐加大了对这一领域的研究，其广泛的应用前景和经济社会价值正使得对智能交通系统的研究成为新兴热门的研究课题。智能交通系统是一个庞大而复杂的系统，本研究中提出的基于视频的城市交通拥挤检测系统就是其中一个最基础的子系统，主要实现对城市主要道路进行实时交通状态的检测和判别，并将准确的检测结果提供给交通管理部门，为其提供必要的决策依据。各国研究人员都展开了对这一系统的研究，但是目前国内成型的交通拥挤检测系统却不多。本文根据当前国内外先进的硬件和软件技术设计了一套基于视频的智能交通拥挤检测系统，并详细介绍了系统各部分及其实现过程。本文中提出的核心算法包括两个方面：拥挤判别主要交通参数的检测算法及交通拥挤检测算法。拥挤判别主要交通参数的检测基于先进的视频检测技术，首先通过简单的背景差法获得车辆目标，但是由于背景差法的局限性使得提取的车辆目标中包含车辆阴影，因此通过归一化互相关算法将车辆阴影去除以获得完整的车辆目标；再运用虚拟检测线和虚拟检测面相结合的改进虚拟线圈检测方法检测本研究中所需的三个交通参数----流量、速度和占有率。交通拥挤检测算法首先分析各国交通拥挤状态的定义并将交通拥挤状态按4个等级划分----畅通、轻度拥挤、拥挤和严重拥挤，并通过借鉴其他领域提出的蚁群算法和模糊C均值聚类算法获得交通拥挤状态的4个等级聚类中心，再通过计算当前交通参数对各等级标准的隶属度来确定当前交通参数所反映的交通拥挤状态。本文中系统实现主要包括两个部分，硬件部分主要介绍了本研究采用的处理平台----TI公司研发的高性能数字信号处理器(TMS320DM642)，以及其视频采集和回放的硬件设备配置；软件部分主要介绍了系统的软件开发环境，并重点讲述了系统各个模块具体软件实现过程，并结合一个具体实例，对本研究中提出的算法进行可靠性和可行性验证。最后对本文系统做了全面总结，并提出了本系统存在的不足及本人对于系统中有待改进部分的构想和思路。更多还原

【Abstract】 With the rapid growth of the motor vehicle and the very limited road networkcapacity unbalanced, the major cities in the worldwide all have a big problem ----urban traffic congestion. Practice has proved that it is very difficult to solve the trafficcongestion only with the traffic demand or traffic supply. In china many cities all facewith the embarrassment of no available land to create the new road facilities. At thistime, traffic management becomes particularly important, and the better trafficmanagement can maximize the network capacity, otherwise it will reduce the capacityof the road network. In recent years, an intelligent and efficient means of trafficmanagement have emerged ---- Intelligent Transportation Systems, abbr. ITS.Intelligent Transportation Systems applies the effectively integrate advancedinformation technology, the communication technology, the sensor technology, thecontrol technology and the computer technology to the entire system, and builds aall-round role, large scale , real-time, accurate and efficient integrated transportationmanagement system. Many developed countries and regions have already begun toresearch and use of intelligent transportation system, and China has graduallyincreased the research in this area in recent years, its broad application prospects,economic value and social value make the study of the intelligent transportationsystem become an emerging hot research topic.Intelligent transportation system is a large and complex system, the video-basedurban traffic congestion detection system proposed in this study is one of the mostbasic subsystem. The main fuction of this system is to detecte and discriminate thereal-time traffic status of the main roads in the city, then provide the accurate results tothe public security traffic management department and help them make the rightdecision. Many researchers have carried out many studies of this system, but the wholetraffic congestion detection system is seldom in our country. In this paper, based on theadvanced hardware and software technology design a set of intelligent video-basedtraffic congestion detection system, and introduce all the design details of the system and the implementation process.In this paper, the core algorithm includes two aspects: the traffic parametersdetection algorithm and congestion detection algorithm. The traffic parametersdetection algorithm uses the advanced video detection technology for trafficparameters detection. First, through a simple background difference method to obtainthe vehicle target, but with the limitations of the background subtraction methodmake the extraction of the vehicle target with the vehicle shadow, then the normalizedcorrelation algorithm is used to remove the vehicle shadow and then get the wholevehicle targets; Then combinate the virtual test line and the virtual test face to thevirtual coil detection method to detect the three traffic parameters---- traffic flow,traffic speed and the traffic sharing. In the part of the congestion detection algorithm,analyze the definition of the countries congestion state and then divide the congestionstate in to four levels ---- smooth, mild crowding, congestion and severe overcrowding,then refernce the classical algorithm in related areas ---- Ant Colony Algorithm andFuzzy C-means Clustering Algorithm to get the traffic congestion status of the fourhierarchical clustering center. Calculate the grade standard of membership of thecurrent traffic parameters to detemine the current traffic state of the traffic parameters.The part of the system design in this study includes two aspects. Hardware sectionmainly introduces a processing platform ----TMS320DM642, which is ahigh-performance didital signal processor developed by TI, then introduces somethingabout the hardware configuration of the video capture and the playback; Softwaresection describes the system software development environment, and focus on thesoftware implmentation process of each subsystem module. Then combined with aconcrete example, verificate the reliability and the feasibility of the algorithmproposed in this study.At last, make a comprehensive summary of the whole thesis, showing theshortcoming of this system and some ideas of some parts needed to be improved.更多还原