Development direction and application analysis of highway monitoring system

In recent years, due to the promotion of national policies and the constant development of expressway construction, it is predicted that in 2015, the national expressway network will be completed. The mileage of the expressway will reach 83,000 kilometers, and the local expressway network will build about 30,000 kilometers in five years. As part of the highway electromechanical system, the monitoring system naturally has to keep pace with the times. Networking, high-definition, and intelligent as the industry's development trend has become unstoppable.

Networking to build information technology highway network Although the application of the highway video surveillance system is still relatively mature analog video surveillance system, and this system is mainly based on the early highway segmented investment, sub-construction and other reasons, only one-segment independence Construction monitoring system. Judging from the system composition of the highway electromechanical engineering, the independent composition of the monitoring system, communication system, and toll system cannot meet the development plan of the national highway network in the future, both from the equipment investment and operating costs, as well as the use of management. . With the continuous expansion of traffic volume and transportation scale, the traffic and transportation security risks have also increased. In the past, the “three independent” systems—independent systems, independent use management, and analog video surveillance systems under the independent information model—were apparently unable to share resources due to their lack of resources. The status quo of the inability to centralize monitoring and management runs counter to the development goals of future intelligent modern highways and information technology. If we only pay attention to the current state of application, the disadvantages of the highway monitoring system that cannot achieve network monitoring have also emerged. For example, the current system has a short transmission distance and insufficient expansion capability. Although the current network monitoring system is not enough to replace the analog system, the advantages of the network monitoring system have gradually demonstrated.

At present, the highway network monitoring system can generally be composed of three levels of provincial monitoring centers, regional monitoring centers, and road monitoring centers. After networking, the open platform can integrate vehicle subsystems other than closed-circuit television monitoring systems, pavement status and weather detection subsystems, information dissemination subsystems, environmental detection subsystems, and alarm systems. At the same time, the open platform architecture is modular, standardized, and extensible. In addition, the highway network monitoring system can not only realize the video surveillance function of the road network, but also can perform information management and release, and establish other command functions such as emergency command system. The networked highway monitoring system can comprehensively and macroscopically monitor the road network traffic and operation conditions. In case of traffic jams, major traffic accidents, etc., the monitoring center can take active measures at the first time to link other systems and publish relevant information to each. Sub-control center will adjust the operation of road network to ensure the smooth flow of road network.

Judging from the comparison of all aspects of the monitoring system, the front-end equipment and management platform of the network video monitoring system is more development than the original analog monitoring system. In general, many manufacturers will provide SDK development kits for the development of network equipment, which will facilitate the user's future function development. For example, Jin Sanli's network front-end and management platform can meet. On the other hand, the transmission mode of the network video surveillance system is more diverse, and it can use various transmission methods such as optical fiber and wireless for data transmission.

High-definition comprehensive improvement of monitoring quality If the network is a single upgrade of the highway monitoring system, then high-definition is undoubtedly a real picture quality innovation. At present, in most highway video surveillance systems, the image resolution is only CIF, D1, and other picture quality effects. Once connected to the back-end storage display device, there may be room for improvement in the clarity of presentation. However, high-definition equipment is not the only way to look at the effects of front-end acquisition. High-definition cameras can take more detailed photographs of the passing vehicle license plate numbers and local features of the road network. For video surveillance, image clarity is the most critical and basic requirement. The clearer the video surveillance image and the more complete the picture details, the higher the accuracy of the intelligent analysis function. As we all know, the premise of recognition analysis is to identify the smallest pixel whose picture can meet the recognition conditions. When the target pixel is larger, the recognition is clearer and the analysis accuracy is higher.

In short, the use of intelligent analysis functions is based on the premise of clear image recognition. Compared with SD, HD front-end products have more effective pixels per unit area under the same focal length and distance of field of view, which means they can provide more clear target information for video analysis and processing operations, thereby improving data accuracy. . Whether it is for intelligent front-end analysis mode or back-end platform analysis and processing, high-definition picture quality is an important factor in improving the accuracy of intelligent analysis. It can be seen that high-definition image quality is not only satisfied with a single visual effect, but also provides a more useful analysis environment for intelligent analysis.

Nowadays, for the real recognition of high-definition surveillance, it refers to the concept of overall high-definition, that is, high-definition front-end devices, high-definition storage, high-definition management platform, high-definition decoding, high-definition display and other aspects of the series of high-definition. The overall high-definition system is a real restoration of the live picture. The lack of any one of the links is not sufficient to present full-definition high-definition. As shown in the display, the HD display device compares with the SD display device, which can better process the front-end captured images. The dynamic super-resolution technology of high-definition display devices analyzes and processes the data of each image frame, and processes low-resolution images into high-definition images for display. In addition, for high-speed motion object resolution in the expressway industry, high-definition display devices can be implemented using motion compensation technology. Motion compensation technology uses the previous partial images to predict and compensate the current partial images, thus eliminating the appearance of jagged and trailing images. The phenomenon makes the picture more smooth and clear. Therefore, the overall HD can achieve high-definition picture recovery from the end.

It can be seen that the existing high-definition devices on the market are already in full glory, and the overall high-definition solution is also more diverse. For the existing expressway security system, the following modes can be selected for system construction or transformation: First, the overall HD-SDI or the overall network of high-definition solutions; Second, HD-SDI and network high-definition products, mixed applications and system components; Third, analog, HD-SDI, network HD products integrated solutions. The HD-SDI system can achieve high-definition image acquisition, no-delay transmission, and distortion-free high-definition display, while the network high-definition system can be more convenient for platform construction and system management and distribution. When the distance between monitoring points in the project construction is less than 100 meters, the whole system can adopt the whole HD-SDI system and directly connect to the high-definition matrix through the coaxial cable or the optical transceiver and display the output. This mode is suitable for the high-definition reconstruction of the medium and small-scale expressway monitoring system projects. It can update the equipment while maintaining the wiring status of the original simulation system to meet the user's customary requirements. If HD-SDI is used in combination with a network high-definition monitoring system, the SDI non-compressed high-definition video signal at the front end can be compressed and encoded after the HD-SDI product is captured, transmitted, and displayed, and then packaged into an IP data transmission share and processed. storage. Under the framework of the network system, it can carry out a large and flexible system management, convenient remote access, and the establishment of a large platform. At the same time, through the use of HD-SDI high-definition video surveillance screen, the entire system of monitoring results to the extreme.

Intelligent analysis, creating a "brain" highway monitoring system Accompanied by the highway network monitoring system, the development trend of high-definition, the system brought about by massive information filtering and storage needs are urgently needed to solve, how to tap from the massive data Out of useful information, improve monitoring efficiency, I am afraid we must rely on intelligent video analysis to complete.

At present, the intelligent analysis that can be carried out for highway video surveillance includes license plate recognition, traffic event detection and analysis, and video traffic status detection. License plate recognition has been maturely applied in highway toll collection systems. It can automatically register, verify, monitor, and alarm the passing vehicles. Intelligent video analysis of traffic incidents mainly includes: object movement monitoring, object detention monitoring, sudden appearance monitoring, moving path monitoring, and object monitoring. Intelligent analysis of traffic incidents In the captured image area, real-time analysis of vehicle speeding, low speed, retrograde, and object leftovers can be performed for different lanes and traffic conditions. When a traffic accident occurs, the system can quickly link alarms and videos for traffic. Security provides protection.

Traffic condition detection is to automatically identify the traffic status of the road segment through real-time data collected by the front-end. When congestion or congestion of road traffic is detected, the system automatically alarms, and statistics of congestion data are generated, and traffic is distributed to monitoring centers at all levels through the platform. information.

Of course, the future intelligent analysis of highway video surveillance goes far beyond these, and it will become more in-depth with the complexity of traffic information. In addition, it is worth noting that the future of intelligent video surveillance is based on digital, networked video surveillance, and the networking of expressways will directly affect the application scale and application level of intelligent analytics.

Therefore, the development and construction of future freeway monitoring systems will be driven by the development of networking, high-definition, and intelligence.