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IIStudyofanEmbeddedImageMonitoringSystemBasedonARMDiscipline:ControltheoryandcontrolengineeringStudentsignature:Supervisorsignature:ABSTRACTWiththerapidevolutionofdigitalimage,embeddedcomputerandcommunicationtechnique,embeddedimagemonitoringsystembecomesanewresearchinginterest.However,alargenumberofpointlesspicturesaretransmittedbacktothemonitoringcenter,whichincreasescommunicationquantityandsurveillanceload;generally,theimage’sdefinitioninremotesurveillanceislowbecauseofitslimitedtransmissionchannel.Animprovingwayismovingobjectdetectioninthefrontofsystem,andsnatchingahighdefinitionpicturewhenmotionhappensandthentransferringbacktothemonitoringcenter.Thismethodcansettlethecontradictionbetweendefinitionandtransferringspeed.Inthedissertation,akindofembeddedimagemonitoringsystembasedonARMisdiscussed.ThesystemhasthefunctionsofmotiondetectionandpicturetransmissionbasedonGPRS,andimprovestheflexibilityofsettingandthedefinitionofabnormalpicture.ThesystemtakesLPC2210basedonARM7coreasitscentralprocessor,andembeddedOSµC/OS-IIasitssoftwareplatform.Movingobjectdetectionadoptsamethodofdynamicdifferencebackgroundimage,whoseprincipleistocalculatedifferencepictureamongthecurrentframesandbackgroundimagesandtakethemotionadjudgingthresholdwhichownsmaximuminformationentropytodeterminemovingarea;anddynamicallyupdatesbackgroundbyusingKalmanfilter.Thus,thesystemrealizesthejudgmentofthemovingareaunderthecomplicatedchangingbackground.ThemonitoringsystemadoptsembeddedWebservertechnologytosendwarninginformationandon-the-spotpicturetotheremotemonitoringcenter.Thewiredorwirelessremotetransmissionchannel(EthernetorGPRS)canbeadoptedbetweenthecenterandthefrontcontrolpoint,andhasthefeaturesofmutualsupplement,convenienceandflexibility.AndGPRScommunicationterminaladoptsWavecomwirelessmoduletotransmitmonitoringimagethroughwirelesscommonnetwork.Inthedissertation,theprincipleandimplementationofembeddedimagemonitoringsystembasedonARMarediscussed.Experimentalresultsshowthattheimplementedsystemperformswellinaccuratelydetectingmotionandlow-levelFAR；andtheGPRSIIItransmissionissosteadythattheshutdownmomentisfew.Meanwhile,therealizationoftheimagemonitoringsystemprovideainitialplatformforthesubsequentresearch,suchasobjectsorting,objecttracking,remotetransmitting,scenecontrollingetc..KeyWords:imagemonitoring;embeddedsystem;ARM;µC/OS-II;motiondetection;TCP/IP;GPRS;embeddedwebserverI基于ARM的嵌入式图像监控系统研究学科：控制理论与控制工程研究生签字：指导教师签字：摘要随着数字图像技术、嵌入式计算机技术和通信技术的飞速发展，嵌入式图像监控系统己成为当今监控领域的一个新的研究热点。然而，大量无意义画面的回传在增加通信量的同时，并没有减轻监控图像判读的工作量；而受有效传输速率的限制，远程图像监控系统的清晰度一般较低。在前端对图像进行运动检测和分析，并在符合规则时抓拍高清晰度图片传回监控中心，可有效解决清晰度和传输速率间的矛盾。本文提出了一种基于ARM的嵌入式图像监控系统，它在前端实现了运动检测，并采用GPRS无线信道进行远程图像传输，提高了监控系统的布站灵活性和特异图像的清晰度。系统以基于ARM7内核的嵌入式微处理器LPC2210为核心，嵌入式实时操作系统µC/OS-II作为软件开发平台。运动目标检测采用动态差分背景图像法，其原理是利用序列图像中当前帧图像减去背景图像，并采用使信息熵最大化的运动判决门限判定运动区域；采用Kalman滤波动态背景生成实现了背景的动态更新；从而实现了复杂变化背景下图像运动区域的判决。监控系统采用嵌入式Web服务器技术将报警信息及现场图像发送至远程监控中心；中心与前端监控点间可以采用有线（以太网）或无线（GPRS）的远程传输信道，这两种传输方式具有互相弥补、方便灵活的特点。远程传输采用GPRS通用无线分组协议，并采用Wavecom通信模块实现了利用现有的无线公网传输实时远程监控图像。文中给出了系统设计及实现的全过程。实验结果表明，所提出的运动检测算法具有较高的检出率和较低的虚警率；所实现的GPRS传输运行可靠、掉线率较低。同时，该图像监控系统的实现也为后继的目标分类、目标跟踪、远程传输和对现场的控制等研究工作，提供了一个初步的平台。关键词：图像监控；嵌入式系统；ARM；µC/OS-II；运动检测；TCP/IP；GPRS；嵌入式Web服务器ii4.4.2运动目标检测实验.................................................................................................395ETHERNET的图像传输......................................................................................................415.1嵌入式TCP/IP协议栈................................................................................................415.1.1ZLG/IP简介[47].........................................................................................................415.1.2ZLG/IP的SocketAPI函数介绍.............................................................................435.2嵌入式WEB服务器..................................................................................................455.2.1HTTP协议简介[48]...................................................................................................455.2.2嵌入式Web服务器设计........................................................................................465.2.3HTML网页设计......................................................................................................475.3图像传输的实现..........................................................................................................486GPRS远程无线传输的设计与实现..................................................................................506.1GPRS简介.....................................................................................................................506.1.1GPRS特点...............................................................................................................506.1.2GPRS系统结构.......................................................................................................516.1.3GPRS业务解决方案...............................................................................................526.2GPRS传输模块方案设计..............................................................................