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附录一 外文译文视频监控系统是安全防范系统的重要组成部分，是一种防范能力较强的综合系统。视频监控以其直观、方便、信息内容丰富而广泛应用于许多场合。近年来，随着现代科学技术的不断发展特别是网络带宽、计算机处理能力和存储容量的迅速提高一级各种实用视频信息处理技术的出现，视频监控技术也有长足的发展，视频监控进入了全数字化的网络时代，日益受到人们的重视和关注。视频监控系统的发展基本上是从早期的模拟闭路电视监控系统向数模结合的视频监控系统和现在的数字视频监控系统演变的过程，而现在的数字视频监控系统根据技术的发展又分为三个阶段：数字监控的多媒体阶段、数字监控的DVR阶段和数字监控的网络阶段。1.模拟视频监控系统：模拟视频监控系统分为基于微处理器的视频切换控制加PC机的多媒体管理和基于PC机实现对矩阵主机的切换控制及对系统的多媒体管理两种类型。模拟闭路电视监控系统实际上就是许多模拟监控设备的组合，系统主要由“前端设备”和“终端控制设备”以及“信号传输介质”三个部分组成，其中：前端设备主要由摄像机、云台、解码器等，控制设备主要由切换矩阵、画面分割器、监视器、控制键盘、录像机等、传输介质包括电缆、控制线等。随着微处理器、微机的功能、性能、可靠性、结构方式等方面都发生了很大的变化，视频监控系统的构成更加方便灵活、与其它技术系统的接口趋于规范，人机交互界面更为友好。但由于视频监控系统中信息流的形态没有变，仍为模拟的视频信号，系统的网络结构主要是一种单功能、单向、集总方式的信息采集网络，因此系统尽管已发展到很高的水平，已无太多潜力可挖，其局限性依然存在，要满足更高的要求，数字化是必经之路。模拟监控系统的主要缺点有：通常只适合于小范围的区域监控，模拟视频信号的传输工具主要是同轴电缆，而同轴电缆传输模拟信号的距离不大于1Km，双绞线的距离更短，这就决定了模拟监控只适合于单个大楼、小的居民区以及其他小范围的场所。系统的扩展能力差。对于已经建好的系统，如要增加新的监控点，往往是牵一发而动全身，新的设备也很难添加到原有的系统之中。无法形成有效的报警联动，由于各部分独立运作，相互之间的控制协议很难互通，联动只能在有限的范围内运行。2.数字视频监控系统：随着多媒体技术、视频压缩编码技术、网络通讯技术的发展、数字视频监控系统迅速崛起，现今市场上有两种数字视频监控系统类型，一种是以数字录像设备为核心的视频监控系统，另一种是以嵌入式视频Web服务器为核心的视频监控系统。数字视频压缩编码技术日益成熟，计算机的普及化，为基于PC机的多媒体监控创造了条件。这种新型视频监控系统迅速崛起，部分地取代了以视频矩阵图像分割器、录像机为核心，辅以其他传送器的模拟视频监控模式，其优越性主要表现在：PC机的多媒体监控主机综合了视频矩阵、图像分割器、录像机等的众多功能，使系统结构大为简化。由于采用计算机网络技术，数字多媒体远程网络监控不受距离限制。由于采用大容量磁盘阵列存盘器或光盘存储器，可以节省大量的磁带介质，同时有利于系统实现多媒体信息查询。但随着基于PC机的视频监控录像系统的发展，在实际工程使用过程中，也暴露出一些不足，主要是系统工作的不稳定性。基于PC的视频监控录像系统的组成结构为：兼容/工控PC机+视频采集卡+普通/较可靠的操作平台+应用软件。从系统的组成结构来分析：PC机用于24小时不间断工作时，其性能是不很稳定的，工控PC机相对兼容PC机的稳定性有一个档次上的提高，使用于较复杂的工作环境。操作系统：以Windos 98为操作平台的系统，业内人士都知道，Win 98的稳定性是有一定问题的，如果同时应用软件又不是很规范，这样就容易在使用过程中出现工作不稳定、死机等问题，而基于PC机的视频监控录像系统其软件的实现是在Windos 95/98/NT、Unix、Linux等通用操作系统上，同时系统文件、应用软件和图像文件都存储在硬盘上，视频处理必须高密度输入大量数据，同时硬盘要进行多工作，普通的硬盘逻辑已无法适应，以致极易产生系统的不稳定性，造成死机的现象。应用软件：采用简易应用软件的系统是不能够用于安防领域的，视频监控系统的应用软件能力上应支持多任务并发处理，如见识、录像、回访、备份、报警、控制、远程连接等的多工处理能力。视频采集卡：视频监控录像系统通常均为多路输入系统，视频采集卡可采用多卡方式，也可采用单卡方式。一般说，单卡方式集成度高，稳定性会优于多卡方式，很多采用一路一卡的方式很容易形成硬件冲突，其稳定性会有较大的影响。嵌入式系统是以应用为中心，软硬件可裁剪的，适应应用系统对功能、可靠性、成本、体积等综合性严格要求的专用计算机系统，亦即为监控系统量体裁衣的专用计算机系统。嵌入式系统主要由嵌入式处理器、相关支撑硬件、嵌入式操作系统及软件系统等组成，它是集软硬件于一体的可独立工作的“器件”。嵌入式操作系统是一种实时的，支持嵌入式系统应用的操作系统软件，它是嵌入式系统极为重要的组成部分，通常包括与硬件相关的底层驱动软件、系统内核、设备驱动接口、通信协议、图形界面、标准化浏览器等，嵌入式曹组哟系统在系统实时高效性、硬件的相关依靠性、软件固态化及应用的专用性等方面具有较为突出的特点。嵌入式系统的优缺点：系统为专用系统，所以系统小，指令精简，处理速度快。系统数据置于ROM/FLASH/MEMORY。调用速度快，不会被改变，稳定性好。系统处理实时性好，性能稳定。文件管理系统更适合于大量的视频数据。在网络功能、音视频同步等方面也难令人满意。嵌入式视频Web服务器方式，服务器内置一个嵌入式Web服务器，采用嵌入式实时多任务操作系统。摄像机送来的视频信号数字化后由高效压缩芯片压缩，通过内部总线送到内置的Web服务器，网络上用户可以直接用浏览器观看Web服务器上的摄像机图像，授权用户还可以控制摄像机、云台、镜头的动作或对系统配置进行操作。由于把视频压缩和Web功能集中到一个体积很小的设备内，可以直接连入局域网，达到即插即看，省掉多种复杂的电缆，安装方便，用户也无需安装任何硬件设备，仅用浏览器即可观看。嵌入式视频Web服务器监控系统与其他的监控系统的比较有如下特点：不空区域广阔，嵌入式视频Web服务器监控系统的Web服务器直接连入网络，没有线缆长度和信号衰减的限制，同时网络是没有距离概念的，彻底抛弃了地域的概念，扩展布控区域。系统具有几乎无限的无缝扩展能力。所有设备都以IP地址进行表示，增加设备只是意味着IP地址的扩充。可组成非常复杂的监控网络。采用基于嵌入式Web服务器为核心的监控系统，在组网方式上与传统的模拟监控和基于PC平台的监控方式有极大的不同，由于Web服务器输出已完成模拟到数字的转换并压缩，采用统一的协议在网络上传输，支持跨网关、跨路由器的远程视频传输。性能稳定可靠，无需专人管理。嵌入式Web服务器实际上基于嵌入式电脑技术，采用嵌入式实时多任务操作系统，又由于视频压缩和Web功能集中到一个体积很小的设备内，直接连入局域网或广域网，即插即看，系统的实时性、稳定性、可靠性大大提高，也无需专人管理，非常适合于无人值守的环境。当监控中心需要同时观看较多个摄像机图像时，对网络带宽就会有一定要求。视频监控系统的发展1.视频监控系统的发展方向前端一体化、视频数字化、监控网络化、系统集成化是视频监控系统公认的发挥在那方向，而数字化是网络化的前提，网络化又是系统集成化的基础，所以，视频监控房展的最大两个特点就是数字化和网络化。2.数字化数字化是21世纪的特征，是以信息技术为核心的电子技术发展的必然，数字化是迈向成长的通行证，随着时代的发展，我们的生存环境将变的越来越数字化。视频监控系统的数字化首先应该是系统中信息流从模拟状态转为数字状态，这将彻底打破“经典闭路电视系统是以摄像机成像技术为中心”的结构，根本上改变视频监控系统从信息采集、数据处理、传输、系统控制等的方式和结构形式。信息流的数字化、编码压缩、开放式的谢意，使视频监控系统与安防系统中其他各子系统间实现无缝连接，并在同一的操作平台上实现管理和控制，这也是系统集成化的含义。3.网络化视频监控系统的网络化将意味着系统的结构将由集总式向集散式系统过渡。集散式系统采用多层分级的结构形式，具有微内核技术的实时多任务、多用户、分布式操作系统以实现抢先任务调度算法的快速响应。组成集散式监控系统的硬件和软件采用标准化、模块化和系列化的设计，系统设备的配置具有通用性强、开放性好、系统组态灵活、控制功能完善、数据处理方便、人机界面友好以及系统安装、调试和维修简单化，系统运行互为热备份，容错可靠等优点。系统的网络化在某种程度上打破了布控区域和设备扩展的地域和数量界限。系统网络化将使整个网络系统硬件和软件资源的共享以及任何和负载的共享，这也是系统集成的一个重要概念。从以可以看出，视频技术的发展大致经历了模拟视频、PC视频、网络视频三个阶段，并以网络、通信技术为依托和传输平台。10附录二 外文原文Video surveillance system is an important part of the security system, and it is a comprehensive system with strong prevention ability. Video surveillance is widely used in many occasions for its intuitive, convenient, and informative content. In recent years, with the continuous development of modern science and technology, especially the rapid increase in network bandwidth, computer processing capacity and storage capacity, the emergence of various practical video information processing technologies, video surveillance technology has also made great progress, video surveillance has entered the whole The digital network era has received increasing attention and attention from people. The development of video surveillance systems is basically the evolution from the early analog CCTV surveillance system to the digital-analog video surveillance system and the current digital video surveillance system. Now the digital video surveillance system is divided into three according to the development of technology. Stages: Digital stage for multimedia surveillance, DVR stage for digital surveillance, and network stage for digital surveillance.1. Analog Video Surveillance System: The analog video surveillance system is divided into two types: microprocessor-based video switching control plus PC multimedia management and PC-based matrix host switching control and multimedia management of the system. Analog CCTV monitoring system is actually a combination of many analog monitoring equipment. The system is mainly composed of three parts: “front-end equipment”, “terminal control equipment” and “signal transmission medium”. Among them: the front-end equipment is mainly composed of cameras, heads, Decoder, etc., control equipment mainly consists of switching matrix, picture divider, monitor, control keyboard, video recorder, etc., transmission media including cables, control lines, etc. With the great changes in the functions, performance, reliability, and structural methods of microprocessors and microcomputers, the composition of video surveillance systems is more convenient and flexible, the interface with other technical systems tends to be standardized, and human-computer interaction interfaces More friendly. However, because the form of information flow in the video surveillance system has not changed, it is still an analog video signal. The network structure of the system is mainly a single-function, one-way, lumped-based information acquisition network. Therefore, although the system has developed to a very high level, The level has not had much potential to be tapped, and its limitations still exist. To meet higher requirements, digitization is the only way to go. The main disadvantages of the analog monitoring system are: usually only suitable for small-scale area monitoring. The transmission tool for analog video signals is mainly coaxial cables, and the distance for analog signals transmitted by coaxial cables is less than 1Km. The distance between twisted-pair cables is shorter. This determines that analog surveillance is only suitable for individual buildings, small residential areas, and other small-scale locations. The system has poor scalability. For a system that has already been built, if new monitoring points are to be added, it is often the case that the new equipment is difficult to add to the original system. No effective alarm linkage can be formed. Since each part operates independently, the control protocol between them is difficult to communicate with each other, and the linkage can only be operated within a limited range.2. Digital Video Surveillance System: With the development of multimedia technology, video compression coding technology, network communication technology, and the rapid rise of digital video surveillance systems, there are currently two types of digital video surveillance systems on the market. One is digital video equipment. The core of the video surveillance system, the other is the embedded video Web server as the core of the video surveillance system.Digital video compression coding technology has become more and more mature, and the popularity of computers has created conditions for multimedia monitoring based on PCs. The rapid emergence of this new type of video surveillance system partially replaced the analog video surveillance mode with the video matrix image segmenter and recorder as the core, supplemented with other transmitters. The superiority of the new video surveillance system mainly manifested in the following: Many functions such as video matrix, image segmentation, and video recorder greatly simplify the system structure. Due to the use of computer network technology, digital multimedia remote network monitoring is not limited by distance. Due to the use of a large-capacity disk array storage device or optical disk storage, a large amount of tape media can be saved, and at the same time, the system can facilitate multimedia information query.However, with the development of PC-based video surveillance video recording systems, some deficiencies have also been exposed during the actual project use, mainly due to the instability of the systems work. PC-based video surveillance video recording system is composed of: compatible / industrial PC + video capture card + ordinary / more reliable operating platform + application software. Analysis from the systems structure: When the PC is used for 24 hours, the performance is not very stable, and the PC-based PC is relatively compatible with the stability of the PC. It is used in more complex work. surroundings. Operating system: Using Windos 98 as the operating platform system, people in the industry all know that the stability of Win 98 has certain problems. If the application software is not very standardized at the same time, it is easy to work instability and crash during use. Other issues, and PC-based video surveillance video system, the software is implemented in Windos 95/98/NT, Unix, Linux and other general operating systems, while system files, application software and image files are stored on the hard disk, video The processing must input a large amount of data at a high density. At the same time, the hard disk needs to perform more work. The ordinary hard disk logic can no longer be adapted, so that the instability of the system can easily occur, resulting in a crash. Application software: The system with simple application software cannot be used in the security field. The application software capacity of the video surveillance system should support multi-task concurrent processing such as knowledge, video, return visit, backup, alarm, control, remote connection, etc. Multiplex processing capacity. Video capture card: Video surveillance video systems are usually multiple input systems, video capture card can be multi-card mode, can also be a single card. In general, the single-card mode has a high degree of integration, and the stability will be better than the multi-card mode. Many methods that use the one-card and one-card method are easy to form hardware conflicts, and their stability will have a greater impact. The embedded system is an application-centric, special-purpose computer system that can be tailored to suit the application systems strict requirements for functions, reliability, cost, and volume, and is a special-purpose computer system tailored for the monitoring system.The embedded system is mainly composed of an embedded processor, related supporting hardware, an embedded operating system, and a software system. It is an operational device that integrates software and hardware into one body. The embedded operating system is a real-time operating system software that supports embedded system applications. It is an extremely important component of an embedded system and usually includes hardware-related underlying driver software, a system kernel, a device driver interface, and a communication protocol. , Graphical interfaces, standardized browsers, etc., embedded Cao system has more prominent features in terms of system real-time efficiency, hardware dependencies, software solid-state and application specificity. Advantages and disadvantages of embedded systems: The system is a dedicated system, so the system is small, instructions are streamlined, and the processing speed is fast. System data is placed in ROM/FLASH/MEMORY. Call speed is fast, will not be changed, and stability is good. The system handles real-time performance and stable performance. The file management system is more suitable for a large amount of video data. In the network function, audio and video synchronization and other aspects are also difficult to satisfy.Embedded video web server mode, the server has an embedded web server built-in, using an embedded real-time multi-tasking operating system. The video signal sent from the camera is digitized and compressed by an efficient compression chip. It is sent to the built-in Web server through the internal bus. Users on the network can directly use the browser to view the camera image on the Web server. The authorized user can also control the camera, PTZ, The action of the lens or operation of the system configuration.Since the video compression and Web functions are centralized in a small device, they can be directly connected to the LAN to achieve plug-and-play, eliminating a variety of complicated cables, easy installation, and users do not need to install any hardware devices. Browser to watch. Compared with other monitoring systems, the embedded video Web server monitoring system has the following characteristics: wide area is not empty, Web server of the embedded video Web server monitoring system is directly connected to the network, there is no limitation of cable length and signal attenuation, and the network There is no concept of distance, completely abandoning the concept of territory and expanding the area of control. The system has virtually unlimited seamless expansion capabilities. All devices are represented by IP addresses. Adding devices only means the expansion of IP addresses. Can form a very complex monitoring network. The monitoring system based on the embedded Web server is very different from the traditional analog monitoring and PC-based monitoring methods in the networking mode. Since the Web server output has been converted from analog to digital and compressed, it adopts The unified protocol is transmitted over the network and supports remote video transmission across gateways and routers. The performance is stable and reliable, without special management. The embedded Web server is actually based on embedded computer technology and uses an embedded real-time multitasking operating system. Since the video compression and Web functions are concentrated in a small device, they can be directly connected to the LAN or WAN. The systems real-time performance, stability, and reliability are greatly improved, and no special personnel management is required, making it ideal for unattended environments. When the monitoring center needs to view more than one camera image at the same time, there is a certain requirement for the network bandwidth.The development of video surveillance system1. The development direction of video surveillance systemFront-end integration, video digitalization, network monitoring, and system integration are all recognized as the direction of video surveillance systems. Digitalization is the premise of networking, and networkization is the foundation of system integration. Therefore, the largest video surveillance room is available. Two features are digitization and networking.2. DigitizationDigitization is a feature of the 21st century. It is the inevitable development of electronic technology with the core of information technology. Digitization is the passport to growth. With the development of the times, our living environment will become more and more digitized.The digitization of the video surveillance system should first be the transition of the information flow from the analog state to the digital state in the system. This will completely break the structure that the “classic closed-circuit television system is based on the camera imaging technology” and fundamentally change the video surveillance system from information acquisition. Data processing, transmission, system control and other methods and structures. Digitalization of information flow, encoding compression, open gratitude, seamless connection between the video surveillance system and other subsystems in the security system, and management and control on the same operating platform, which is also the meaning of system integration .3. NetworkingThe networking of video surveillance systems will mean that the structure of the system will transition from a lumped to a hub-and-spoke system. The distributed system adopts a multi-level hierarchical structure and has a micro-kernel real-time multi-tasking, multi-user, distributed operating system to achieve rapid response of the preemptive task scheduling algorithm. The hardware and software of the distributed monitoring system are standardized, modularized and serialized. The configuration of the system equipment has strong versatility, good openness, flexible system configuration, complete control function, convenient data processing, and friendly man-machine interface. And the system installation, debugging and maintenance are simple, the system operation is mutual hot backup, fault tolerance and reliability. The network of the system breaks the geographical and quantitative boundaries of deployment areas and equipment expansion to some extent. Networking of the system will enable the sharing of hardware and software resources of the entire network system and any sharing with the load. This is also an important concept of system integration. From the above, we can see that the development of video technology has gone through three stages: analog video, PC video, and network video, and is based on network and communication technologies and a transmission platform.
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