Solution of intelligent network video monitoring s

In recent years, with the deepening of the informatization reform of the railway system, network technology has been widely used in the daily production and management of the railway system. At present, as an important national transportation department, the daily stable operation of the railway system determines the normal operation of national production and life. In addition, there are many railway system departments, scattered locations, and complex on-site environment, which have become the main obstacles to daily maintenance

the implementation of remote network video monitoring system within the railway system will greatly solve the above contradiction. The remote network video monitoring system adopts embedded web server technology. Operators and department leaders can use the existing computer network and office computer of the railway system to realize the monitoring of all a=f squared divided by 250 multiplied by D at the dispatching center or local locomotive depot to monitor the environment at the site or local crossings, stations and along the railway, greatly reducing the workload of daily personnel patrol and facilitating the timely detection of hidden dangers, Ensure safe production

II. Demand analysis:

1. Taking advantage of the existing network conditions of the railway, in view of the scattered and difficult management characteristics of railway monitoring points, the specific functions of the railway network video monitoring system are:

2. Focus on the densely populated places such as the station square, waiting hall and passenger passage, and monitor the safety of multiple sites through the multi screen display function of the monitoring system

3. The railway freight yard has a wide range, so it is necessary to monitor the security of the freight yard at any time

4. Use proprietary communication lines to centrally monitor unattended substations, lighting and other important distribution equipment along the railway, and timely understand the operation of the equipment

5. Monitor the flow of people and vehicles at important crossings and intersections at any time to ensure the safe operation of vehicles

6. The electronic map function is used to comprehensively and intuitively reflect the operation conditions along the railway with static image display. It has the function of TV wall. The dynamic display system of the required video signals, digital signals and analog signals can connect the driving speed limit system in time according to the warning signals of the meteorological information along the way, and respond to the emergencies such as debris flow, flood, traffic accident, etc

1. Distributed monitoring and management structure:

the so-called distributed monitoring and management refers to that in a large-scale monitoring and management system, in order to avoid the management omission of the top organization due to lack of time, the whole system is divided into several blocks/groups, and multi-level management, just like a country from the central to provinces, cities, districts and counties, which is subordinate to management at all levels. A city can only govern the districts in the city, and cannot collapse the urban management, And the central organization at the top can be managed to the grass-roots level through the intermediate organizations at all levels. As shown in figure 1:

2 Duplex visual intercom:

in the structure diagram of Figure 1, the partition center and the stations under its jurisdiction can have two-way intercom calls through the ALPUS video codec; When there are two or more call requests at the same time, the system will automatically sort in chronological order and answer the intercom. Two way intercom can be carried out between the central center and any zoning center. Similarly, when there are two or more calls at the same time, intercom cannot be carried out between the zoning center and the non jurisdictional station. At the same time of two-way intercom, the center also hopes to see the image of the site, so the synchronous transmission and timeliness of image and voice are the key to the system. If the transmission bandwidth is limited, the image is only transmitted individually from bottom to top, so it is only visible individually, that is, the superior can view the image of the subordinate, while the subordinate cannot see the image of the superior. This not only conforms to the management system, but also has a relatively high cost performance

III. system composition

the remote network video monitoring system based on Embedded Web server is adopted, which is greatly different from the traditional analog monitoring and PC platform based monitoring in group mode. The whole monitoring system is responsible for the amplifier range conversion, data collection, data transmission The selection of experimental mode and LCD system are mainly composed of three interconnected parts: field equipment (or substation equipment for short), channel transmission equipment and dispatching/centralized control station, and dispatching center monitoring terminal (or master station equipment for short). Now they are introduced respectively

1. Substation equipment

is mainly composed of front-end equipment and elopsnet video codec. Front end equipment, such as monitoring cameras (color or black-and-white, fixed or movable PTZ, fixed focus or zoom), and various alarm input/output devices are completely consistent with the equipment used in traditional industrial television. Therefore, the core of the substation equipment is the elopslo video codec. This system adopts an embedded operating system, which can integrate the camera access and control, image digitization, compression coding, and network transmission into one device. It is very convenient to install and debug. At the same time, because this equipment can be set and managed remotely through the network, there is no need for on-site routine maintenance. In the actual installation and use, the real-time, stability and reliability of the system are greatly improved compared with the microcomputer platform, and the daily maintenance workload is quite small, which is very suitable for the unattended environment. After the video server is installed in the remote network video monitoring system, it can completely replace the role of video matrix. Not only is the equipment easy to install and debug, but more importantly, it can support multiple users in the network to watch or control all monitoring sites at the same time, which is of more important significance for monitoring work

2. Channel transmission equipment

this part of equipment should be selected according to the communication channel. At present, there are mainly three types: Digital dedicated line (wired or wireless), ISDN and network (wired or wireless). To achieve satisfactory image quality, the channel bandwidth is recommended to be above 384kbps

3. Master station equipment

master station equipment mainly realizes the centralized management of login users and sub station equipment, as well as video image decompression, storage and other functions. A simple master station is composed of one or several monitoring terminals, which often complete one-to-one or one to many video monitoring tasks in the form of time sharing. If alarm, video and other monitoring tasks need to be realized, the main station equipment can add alarm database server, digital video database server, multiple monitoring terminals and a large number of auxiliary monitoring terminals. In this way, users only need to establish a video system server in the Railway Bureau dispatching center. Bureau leaders, chief engineers and relevant departments can use the existing office computers to establish sub control terminals. Several monitoring terminals can also be conveniently established in the dispatching station and centralized control station. These monitoring terminals do not need to lay special microcomputers and video/control cables. They can monitor stations, crossings, business halls and other different places within their jurisdiction in the office by using Internet Explorer, and complete user management through the video system server; Locomotive depot and camera grouping; Remote control priority setting and scheduling; Video image storage, retrieval and playback functions. The electronic map module provided by the system runs together with the server software of the monitoring center. You can view images with IE browser on any client, which can easily view each monitoring site and intuitively display maps at all levels; It is worth mentioning that this set of video system adopts Web technology and standards, which can be compatible with other systems such as enterprise MIS system, and has become an important part of enterprise internal information management

the central server can transmit the video stream to the TV wall of the center, and the personnel on duty can clearly and intuitively monitor the video transmitted by each substation and make decisions in time. This system can also be perfectly integrated with GIS system, according to Zhou Guomei, deputy director of China ASEAN environmental protection cooperation center, so as to minimize the impact of various geographical environment changes

4. System function

24-hour video monitoring of key parts of the computer room in real time, and digital video recording can be used later. The system can connect a large number of alarm devices, such as door magnets, infrared, smoke detectors, glass breakers, etc. once abnormal signals are captured, the system can automatically alarm, upload alarm information, and conduct local and remote digital video recording

the access control interface can be added to the system, which can seamlessly connect the access control system and strengthen the management of personnel entering and leaving the machine room. Through audio and video monitoring, the management personnel of the computer room can see the working conditions of the equipment in the computer room and the on-site staff anytime and anywhere, and can also talk with local personnel to strengthen the interaction of the management of the computer room

combined with the local power distribution system, such as primary power distribution, secondary power distribution, ups and lightning arrester, the staff can get the power supply of the machine room anytime and anywhere

combine a large number of professional environmental monitoring equipment in the system to timely respond to the data of air conditioning system, temperature and humidity, fresh air fan, water leakage monitoring and other equipment room environmental protection equipment

the system can set the upper and lower limit of alarm for all equipment. If any equipment data exceeds this range, the system can generate an alarm signal. And it can link equipment in a certain range, such as video, backup generator, sprinkler, fresh air fan, etc

the monitoring system should have friendly man-machine dialogue interface and Chinese character support ability; The fault alarm shall have obvious acoustic optical form. 4、 System features

1 Digitalization: with the continuous improvement of science and technology, digital products are integrated with powerful functions, flexible operability, network server, remote management and other functions

2. Full Networking: through the WAN network, the network video server can transmit high-quality images, sounds and control signals, which is very convenient for managers to view any way of images and intercom anytime and anywhere

3. Perfect combination of digital technology and analog equipment

4. Reliability: the system is composed of equipment with reliable performance and mutual compatibility to ensure the long-term reliable operation of the system

5. Flexible and practical: the design of the whole system is based on user needs, user-oriented, very humanized, easy to operate and practical

6. Scalability: the selected equipment has strong compatibility and scalability, which is convenient for the enrichment, improvement and upgrading of the system

v. system topology:

topology

as an important national transportation department, its daily stable operation determines the normal operation of national production and life. In addition, there are many railway system departments, scattered locations, and complex on-site environment, which have become the main obstacles to daily maintenance. The implementation of remote network video monitoring system in the railway system will greatly solve the above contradiction. Establish a remote network video system. Operators and department leaders can use the existing computer network and office microcomputer of the railway system to realize the monitoring of all monitoring sites or local crossings, stations and the environment along the railway in the dispatching center or local locomotive depot, which greatly reduces the workload of daily personnel inspection, facilitates the timely detection of hidden dangers and ensures safe production

System Design Description:

1) first, establish a wireless network covering stations, freight yards and crossings

wireless network technology is a very mature technology, with international standard IEEE802.11 series standards. According to the needs of the railway department and the analysis of specific geographical conditions, the system design scheme takes the way of high-power base stations plus special pattern antennas as the design principle. If there are special places that cannot be covered, then consider using relay mode to achieve targeted and comprehensive coverage of wireless signals

2) monitoring point: using embedded technology