【正文】 ndreds around the general, occupied bandwidth depending on the specific exercise how many different picture. Deficiency is relatively poor quality of some, occupied bandwidth screen with movement and the plexity of substantial change. In short, this is a closedcircuit television monitor so that the item highly automated, highly efficient elegant fortable, convenient and speedy, highsecurity environment of space. System mainly consists of three parts: frontend monitoring。 workstation (client). The installation of video surveillance point: Color night vision cameras and color of high illumination cameras and other equipment installed in the designated location, providing 12 VDC power supply and video interface. Monitoring Centre According to specific requirements of schools, teaching areas (of nine school buildings), by Information Centre and the Centre set up a control extensions, the clinic, teachers dormitory (a total of two dormitory) and garage, the living quarters of students (total 12 dormitory) to install a control extensions, canteens, supermarkets, sports centre, student activity centre, Training Center, the south gate, Simon and the North have set up a control extensions, in the host control centre set up to monitor the entire campus that in turn control the first time police information and criminals every move in the room were Baoweichu president and the establishment of a control center. DVR control center through the control system can be arbitrary view the full image (to authority), and a monitoring point for the implementation of cloth Chefang, video playback 3 operations (to access). Control centers are located in the President39。s time. Server software installation is plete, the system automatically configures the video data storage path, users may need to use the serverside management software to change configuration, the system supports distributed video storage for largecapacity storage may be provided. Monitoring center can be set up in a monitoring station, monitoring workstation as a system administrator user of the system in equipment and user management, including video data maintenance and management. Workstations can be connected with the projector system can be used to monitor or demonstration. monitoring workstation (client) Network puter users to install DVR client software, landing by the system administrator to provide legal status and server access rights, can bee a monitoring station. Client software, including: system configuration tools, control software, and audio and video playback software enquiries. System configuration tool: video can be set to undertake the lens division, video server settings, among others. Monitoring Software: 19 frame to provide the realtime monitoring, Haeundae or ball machine control. Enquiries playback software: According to the lens name, date / time, video and other types of enquiries, and intervals for the results. Monitoring centre is just a puter as a server (under video server configuration corresponding amount of demand for hard disk), can be configured as a workstation monitoring systems management and settings to use, when necessary can be configured a projector and workstations connected to peacetime surveillance or system demonstration. Implementation of the system The system of cameras and lenses, Haeundae, protective enclosures, monitors, and other traditional products can basically part of the optional, but it should be used costeffective products. The system used in highdefinition color Huamianbangeqi 16 Huamianbangeqi, automatic image switch selectable switching time, a functional image freeze. Video switch matrix by the Chengdu Branch of the MJ516 video switch matrix, and the ways for its 16way input, the output of five trade unions Road. It is Chinese characters superimposed clock system uptime enquiries, a powerful builtin functions such as Chinese Character Library. It is critical to provide the relevant 4 agreements for secondary development. The software is to use some of the major video capture card provided by the API function and video switching matrix provided by the munication protocol software and services produced receive software, which is oneway video signals and control signals are twoway. Through LAN control mands can be issued. Conclusion This paper illustrates how the present technological conditions, assembled into one economical and reliable, and patible with the advanced monitoring system. This system suited to the local area work (10/100 M) on the realtime transmission of digital video images. Multimedia is a simple monitoring system (including video only). Believe that with puter technology, video technology, control technology, munications technology development, work monitoring will also enjoy broad prospects. An analogtodigital converter An analogtodigital converter(ADC) is used to convert a continuously variable signal to a corresponding digital form which can take any one of a fixed number of possible binary values. If the output of the transducer does not vary continuously, no ADC is necessary. In this case t