Peace city construction is a huge and complicated system engineering, especially for the peace of the city core, video monitoring system, due to business needs, platform scheme selection within the region difference, and do not have a unified standard, protocol, to create a unified comprehensive city level security monitoring platform, to realize interconnection and transparent to users of video resources, system integration is difficult. Especially for local video monitoring system has been built, how to realize the integration of the analog and digital technology, realize the comprehensive monitoring platform, be in peace city security system construction in a more difficult problem.
One, mold, several of the characteristics and present situation of monitoring system
In the development of video surveillance technology, video monitoring system has experienced a from the analog signal monitoring system, to the analog combining ways of remote video monitoring system, to fully digital network video monitoring system development process. Different stages of technology development each form has its typical characteristics of security video surveillance solutions, and with their own characteristics and is widely applied in all kinds of security monitoring field. Here are several kinds of common video monitoring construction scheme:
1, it is a delegate with analog matrix a strong response, link exclusive dedicated analog monitoring system, mainly used for the control of image quality, real-time response to demand higher places, mature technology, good real-time performance. It is worth mentioning that with the development of security technology, most mainstream brands of analog video matrix, the system has better solved itself multi-stage networking, using multiple transmit video from video light end machine networking of images of simulated images. However, due to its own technical characteristics restrictions, simulation monitoring in networking link cost, image call controls on the number of concurrent there is difficult to break through the bottleneck. Application is common in a certain area, therefore, the class system independent monitoring system, or is the medium and small video networking system.
2, it is part of the digital system (DVR), mainly in digital video monitoring, storage, transport developed digital monitoring system, the system breaks through the aspects of the limitations of simulation in video matrix system network, through the front-end digital video signal after storage and processing, and based on the TCP/IP network for video streaming transmission forwarding, realize the video multi-tiered remote networking call function, reduce the link cost video networking system, and through the media streaming forward, virtual digital matrix switching technology implementation and improve the video networking on the number of concurrent users. In today's application, the system is relatively common case is small system or a separate area coexist with analog matrix monitor video networking system of medium and small area.
3, it is the third generation of fully digital video monitoring system. This system, which is based on TCP/IP network, through the adoption of IP camera, transmission, storage of NVR megapixels hd treatment, emerging digital video technology, such as network multicast protocols from the front end is the digital signal, the output of the image acquisition device based on TCP/IP protocol, streaming media, network multicast technology was adopted to realize video multiplexing transmission on the Internet, and through the network virtual host (digital) matrix control (IPM) to implement of the whole monitoring system of command, scheduling, storage, authorization control, and other functions. Fully digital video monitoring system in video processing and application of intelligent monitoring areas there is a huge advantage, is considered to be in the future the trend of the development of the video monitoring system, the industry has also been a part of a mature platform product, however, the fully digital system also has the construction cost is still on the high side, some problems such as transmission link security remains to be further improved.
In the construction of safe city, the above three kinds of system often co-exist, and within the scope of their respective regional form a relatively independent system of regional autonomy or connected to the Internet. And in peace the city's video monitoring network system, to achieve the above all kinds of independent or local area network video monitoring system connected to the Internet, realize transparent to the user's city level security network unified platform, is a key problem in the construction of safe city.
Second, mold, several mixed monitoring system's basic architecture and implementation
To establish a unified, comprehensive city level video monitoring platform, implement platform, different regions of local solution between the Internet and video resources, must according to the above the different characteristics of the common types of video networking system breakthrough technology, the differences between the agreement between the existing scheme, implementation of each system under the digital platform scheme compatible. Solution is an ideal of architecture, by control code with the video stream flow distribution processing, transmission, combining with the authority to establish the multiple levels of allocation and certification system, and the hierarchical level of concurrent video streaming multiplexing forwarding call layer, thereby finally realize video monitoring network platform for transparent to users. Here in this paper, the video stream and control flow diversion, the establishment of the authority distribution and certification, and multiple levels of several key aspects, such as the concurrent load balancing mode of the basic framework of video monitoring platform, to introduce respectively.
1, the video streaming transmission architecture
Source video stream in the front-end digital communication is typical of the way there are mainly three kinds: one is for all access to the front end video, through video distributor in two, all the way into the matrix as the source of the local video call control monitoring system, all the way through the DVRS or other digital video storage transmission on the encoder, and through the video monitoring platform for software integration of DVR and encoder to realize the video streaming on demand, switch and playback; Later, the second is for the front-end video access matrix in reserve a multiplexed output video switching matrix as a source of video coding, controlled by the monitoring platform through video gateway (VRT) implementation of video matrix to take over the local area and the remote control, realize image source selection and switch; Three is for pure digital video stream of the system, and generally taken from video system of streaming media server or video multicast stream, through the control of the pure digital monitoring system, called agreement, realizing the SDK integration stream for decoding controls.
2, control the implementation architecture
To the resources of different technology platforms interconnected control, call, is one of the difficult points of setting up a comprehensive city level image monitoring platform, the different control scheme adopts control technology, great differences of the agreement, even in the same platform, different brands of equipment control is implemented also have individual differences, in order to realize the unification of the transparent to the user interface, unified terminal one-click front-end video resources without differentiation call, control is a big challenge. To achieve this goal, we adopted a unified image method to control the gateway (VRT) devices, form a unified monitoring control flow level, through the image control gateway (VRT) on different platforms and products control protocol translation and expansion of compatibility, finally realizes the transparent to users of front-end video calls and control of resources.
