Analyze the current status and development trends of "safe city" construction

[Smart City Network] The concept of "safe city" is not only a content of social security, but also includes urban traffic conditions and urban fire services, as well as various man-made disasters (including wars, terrorist attacks, major fires that threaten urban security, Environmental pollution, etc.) and early warning and warning of natural disasters. As a very large and comprehensive management system, the safe city construction project not only needs to meet the needs of public security management, urban management, traffic management, emergency command, etc., but also takes into account image monitoring in disaster accident early warning, production safety monitoring, etc. needs, and at the same time, the integration of supporting systems such as alarms and access control and the linkage with the broadcast system must also be considered.
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As an important part of the public safety technical prevention system, safe city construction is closely connected with the security industry. The safe city alarm and monitoring system is a huge system that integrates security prevention technology, computer application technology, network communication technology, video transmission technology, access control and other high and new technologies. It has a large overall investment, high technical requirements, a wide range of users, and many links. systems engineering. The purpose of its construction is to further enhance the important means and reliance of public security organs in managing society, public security prevention and control, combating crime, maintaining stability, and ensuring security by building an integrated, multi-functional, comprehensive public security prevention and control network covering the entire city. It plays a role that other preventive facilities cannot play in traffic management, preventing and stopping crimes, resolving disputes, handling public security and criminal cases, and providing clues and evidence for public security investigation and solving cases.
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As a project promoted by the government, Safe City has a clear driving role in the development of the security industry. In the past two years, with the popularization of information technology, Safe City construction has put forward new requirements for security products and technologies, gradually promoting the traditional security concept. With the shift to the concept of maintaining public safety and "comprehensive security", safe city construction has become part of urban infrastructure construction. With the application of new technologies such as the Internet of Things and cloud computing, safe city construction is gradually being integrated into smart city construction. This article will focus on the application of security products and technologies in safe city construction and the development trends of safe city construction to elaborate on the current situation and development of safe city construction.
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1. The origin and current situation of “safe city” construction
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The construction of safe cities originated from two major projects: the "Technology-based Police Strengthening" strategy and the construction of urban alarm and monitoring systems, the "3111" pilot project. Pilot projects were first launched in four cities: Xuanwu District in Beijing, Jinan in Shandong Province, Hangzhou in Zhejiang Province, and Suzhou in Jiangsu Province.
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In June 2004, in order to comprehensively promote the implementation of the strategy of strengthening police through science and technology, the Ministry of Public Security and the Ministry of Science and Technology launched the first batch of demonstration cities for strengthening police through science and technology in 21 cities including Beijing and Shanghai. Subsequently, the General Office of the Central Committee of the Communist Party of China and the General Office of the State Council required all departments and localities to actively promote various forms of safety in "safe communities", "safe families", "safe campuses", "safe hospitals", "safe markets" and "safe oil areas" Create an event.
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In order to lead from one point to another, the Ministry of Public Security further proposed the "3111 Pilot Project" for the construction of urban alarm and monitoring systems, selecting 22 provinces to carry out pilot projects for the construction of alarm and monitoring systems at the provincial, municipal and county levels, that is, each province determines one city. A city that has the conditions will designate a county, and a county that has the conditions will designate a community or block as a pilot project for the construction of alarm and monitoring systems. So far, the construction of urban alarm and monitoring systems has been rapidly carried out across the country, and has gradually become a key project for safety construction in various places.
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Currently, with the gradual advancement of the network construction of video surveillance systems and the integration and sharing of video image information, in February 2012, the Ministry of Public Security issued the "Task Statement for the Integration and Sharing of Video Image Information of National Public Security Agencies" (hereinafter referred to as the "Task Statement") , clearly stipulates the work tasks of the national public security agencies on the integration and sharing of video image information in the next three years.
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With the release of the "Mission Statement", the construction of video image sharing in various places has begun. This also means that the future development direction of safe city alarm and surveillance system construction is to integrate social network resources, public security dedicated and social video surveillance resources. , regional alarm network system resources, community security system resources, police geographic information system resources, traffic condition monitoring system resources, traffic violation identification system resources, traffic guidance system resources, checkpoint vehicle identification system resources, disaster forecasting system resources, environment All types of resources closely related to urban security, such as pollution monitoring system resources, can build a stable, reliable and powerful urban emergency communication command system through information exchange, resource sharing, urban management mechanism innovation and business process reconstruction.
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Under the current situation, the construction of a safe city alarm and monitoring system is to comprehensively utilize and process police-related information resources such as surveillance video, geographical information, electronic police and checkpoint identification, and be oriented by the business applications of different police types. Information collection, processing and data exchange realize application services and resource sharing for different professional police services on one platform, create a standardized, universal and intelligent "urban police information comprehensive management platform" and build a "big security" system , creating a new era of "safe city" construction.

2. Application of security technology in the construction of “safe city”
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As the construction of "safe cities" continues to advance, security products and technologies have been further promoted and applied. At the same time, new requirements have been put forward for security technology innovation and product performance applications.
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Video surveillance is a core component of the construction of "Safe City". At present, as the construction of "Safe City" is advanced in depth. On the one hand, system construction is expanding from first-tier cities to second-tier and third-tier cities, and from large and medium-sized cities to districts, counties, and towns; on the other hand, although in the current safe city project, simulation systems and analog-digital combined systems are still relatively mainstream applications , and will coexist for a long time to come. However, the urban video surveillance system is transforming from an analog system to a fully digital system, and at the same time, it is a development trend to gradually upgrade and transform the previously constructed analog system into a fully digital system.
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Before the early 1990s, the construction of "safe cities" was mainly based on closed-circuit television monitoring systems based on analog equipment, which was called the first generation analog monitoring system. It takes video matrix, splitter, and tape recorder as its core, uses a video switching matrix for networking, and multi-channel video optical transceivers to upload video images. The technology is mature and has good real-time performance, but it lacks remote functions.
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In the mid-to-late 1990s, digital-analog surveillance systems appeared, and hard disk video recorders (DVR) were applied to analog surveillance systems. It is mainly transmitted through computer networks and processed using intelligent computer software. Although this mixed-mode monitoring solution can achieve remote transmission, the front-end video to the monitoring center uses analog transmission, which has limitations in distance and location.
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By the beginning of this century, fully digital video surveillance systems began to be widely used. When the video is output from the front-end image acquisition device, it is a digital signal, and the network is used as the transmission medium. Based on the TCP/IP protocol, streaming media technology is used to realize the multiplexing transmission of the video on the Internet, and through the network virtualization ( Digital) matrix control host (IPM) to realize the command, scheduling, storage, authorization control and other functions of the entire monitoring system.

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(1) High-definition network video surveillance technology
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In the early days of safe city construction, traditional analog video surveillance and alarm networking systems were limited by the level of technological development at that time. Most TV surveillance systems could only monitor on-site. Although the surveillance network alarm network can transmit alarm information over long distances, However, the existing alarm information transmitted is simple, cannot transmit video images, and cannot accurately understand the situation at the incident site in a timely manner. It is difficult to confirm alarm events, and the system efficiency is low, which virtually increases the workload of security personnel.
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With the popularization and application of computers, the rapid development of network communication technology and image compression processing technology, the construction of safe cities adopts the latest computer, communication, image, digital coding, decoding, storage processing, and intelligent analysis technologies through urban optical fiber high-speed networks. or broadband network to transmit data signals. It can not only carry out long-distance monitoring, image transmission, and network alarms, but also has the functions of intelligent control, convenient historical data query, and large data storage. The cost is reasonable, and it can more effectively prevent and combat crime, taking safe city construction to a new level.
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From the perspective of the architecture of the network video surveillance system, on the one hand, with the rapid growth in the number of front-end video collection devices and the deepening of network complexity, more and more video image processing functions are transferred to the front-end; on the other hand, the scope of monitoring It also increases the difficulty of management, and the degree of centralized management of network video surveillance systems is gradually increasing. In addition, network video surveillance systems are developing towards a surveillance network of “unified deployment + data sharing”.
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High-definition video surveillance is an important part of safe cities. Due to the application of high-definition technology, the clarity of collected images has been greatly improved, making the system innovative in recognition of license plates, facial features, clothing features, etc. The breakthrough provides powerful scientific and technological means for the police to track fugitives, thereby greatly reducing the crime rate in the city.
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High-definition video surveillance has typical cross-region, cross-industry, and cross-application characteristics. In terms of geography, the entire system involves the networking of grassroots police stations, district and county public security bureaus (bureaus), and the three-level monitoring center of the municipal public security bureau. In terms of industry, its monitoring resources cover many scenes both inside and outside the public security system, including roads, security checkpoints, important units, key locations, public places, firefighting, schools, communities, hotels, banks, industrial factories and mines, etc. In terms of application, the system must complete various functions such as image monitoring, video playback, intelligent identification, and alarm linkage.
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With the maturity of high-definition network monitoring system technology, the application of high-definition network monitoring systems in urban alarm and monitoring systems has emerged. The use of high-definition network cameras will bring a leap-forward development to the construction of urban alarm and monitoring systems. Because of its application, it will put forward higher requirements for network equipment, IP storage equipment and intelligent system management. Storage will gradually transition to IPSAN or NVR, and back-end digital matrix and display devices will be adopted accordingly, bringing the era of large data transmission, control, and migration ahead of schedule. Due to the higher image quality, the application level of video analysis technology in case analysis and judgment work has been greatly improved, overcoming the original shortcomings of low video quality and limited practical use value, thus raising the application of video in the public security industry to A new stage of "producing significant value".
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(2) Changes in storage mode
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In the construction of safe cities, the back-end storage system takes DVR as the core of development. In the early days, embedded DVR + central management server was used, and video forwarding servers were added to nodes. However, with the continuous increase of city monitoring data and the convenience of network services, the back-end Storage technology is undergoing subtle changes.
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The current construction of "safe city" is a security monitoring system with high complexity and large network integration. The purpose is to realize the network monitoring function of multi-level platforms, so it requires large-scale video network storage to be possible.
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Video surveillance data is basically stored in a process such as camera server storage device. Data from multiple cameras is sent to the data processor server for encoding and processing, and then stored in the form of data streams on the back-end storage device. For video surveillance data, since network video surveillance is based on network-based audio and video stream transmission, a large number of audio and video stream transmissions will have a great impact on the performance of the video surveillance management server. The more data there is, the harder the video surveillance management will be. The server's scheduling of I/O operations and cache management become more complex. There are often situations where multiple cameras are targeting a single server, multiple servers are targeting a back-end storage device, frequent access to storage devices and multiple The storage requirements of multiple servers for each camera require a large amount of resources, affecting its processing capabilities. At the same time, video surveillance data is streaming media all the time, and cannot be paused during transmission and storage, otherwise the video information will be lost, so it cannot be transmitted and stored as a single file.
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From the perspective of surveillance equipment, with the increase in cameras, the application of high-definition cameras, multi-angle camera technology, and increasingly higher file storage periods, it is also necessary to determine whether storage equipment can meet the growth in demand for a long time to come. problem to be solved.
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Therefore, the storage requirements of video surveillance have the following characteristics:
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First, the demand for storage capacity is relatively elastic. The storage capacity will increase exponentially with the improvement of picture quality, increase of picture size, and increase of video lines.
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Second, the storage performance requirements are not high, but it needs to be able to meet long-term continuous data reading and writing. The data traffic is large but the number of access requests is low.
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Third, the scale and radiation area are getting larger and larger. The current "Safe City" project covers many cities across the country. In some cities, there are tens of thousands of cameras, and the total storage capacity requirement is hundreds of TB.
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Fourth, the requirements for clarity are getting higher and higher. The resolution of the monitoring system has been improved from ordinary 352×288 to 704×576, and the code stream rate has developed from 300Kbps and 500Kbps to 1Mbps and 2Mbps.
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The above requirements have put forward higher requirements for the storage part of the video surveillance system. In safe city video surveillance, the stored data is no longer simple video data, but a data source for image analysis by the surveillance resource usage department. The surveillance system The application model determines that the storage system must be able to support high-level security, rich permission management functions, high data sharing, high performance of data reading and writing, and flexible scalability.
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At present, in the "Safe City" construction project, the ideas of distributed storage and centralized storage are still in fierce competition. From an objective application point of view, with the application of network front-end, the supporting storage modes in the Safe City project are distributed storage and centralized storage. They are all just technical, the key depends on how to meet the needs of users. In practical applications, what the public security industry values is not how to build a storage architecture, but how to effectively integrate a large number of video sources with business management, and how to effectively utilize these massive storages. Therefore, multiple storage forms need to coexist.