Software large-scale urban
[Product Overview]： 1, system structure
1.1 system architecture components
City Surveillance System composition can be divided into front-end equipment, lines, and
communications facilities, back-end equipment, servers and other
components.
Front-end and from front-end data acquisition equipment, data
compression equipment, relay transmission equipment components.
Front-end data acquisition equipment which is generally the ball
machine, Haeundae, ordinary cameras, bolt, probes and other
equipment, while the data compression equipment from the general
network video servers, digital hard disk video recorders,
PC-embedded hard disk recorders, and other components, Relay
transmission equipment, including routers, switches, and so on
network transmission equipment.
Comprehensive equipment reasonable structures from the city
structure of the monitoring system described as follows:
Figure 1 Monitoring System network topology
From the network video server group composed of front-end
equipment, to fully meet the requirements of modern network,
because the network is becoming more and more sound, audio and
video transmission network than traditional local storage devices
have many more advantages.
Can be seen from the figure, the entire system is divided into
control of the data acquisition, processing of data exchange, data
application layer, which every level of the corresponding function
independently. Every level technically completely independent and
interrelated with complete data from the bottom, it could simply
mean that for the next level, a level for the provision of data
services, on a level of control or controlled in the next level.
The system can be used Distributed Management (according to
different area, the establishment of a control center), centralized
management can also be used (only the establishment of a Centre),
is modular in design, no matter what kind of way, the management
and operation are Like, no essential difference between, the only
difference is: the former equipment subregional placed to take full
advantage of network resources; Monitoring Centre on the latter
network resource requirements higher.
1.1.1 Data Acquisition layer
Data acquisition layer is the only field data collection equipment
group, the core of the network video server equipment (Network
Video Server, acronym: NVS, the paper after the short NVS).
Primarily responsible for on-site audio and video data collection,
and can switch output signal on the scene to control external
equipment to the scene to collect real-time data and the purpose of
resolving crisis situation. From the map can be seen in the data
acquisition of the main functions:
Figure 2 of the Data Acquisition
NVS can be seen from the above figure, the main function:
① scene video (cameras), audio (pickups, microphone) for
high-quality audio and video compression;
② acquisition Alarm (alarm sensors), and other analog or switching
of signals acquisition and processing;
③ in accordance with international standards will be the signal
into a digital signal and digital compression, transmission;
④ case of the police, in accordance with the user's settings will
be necessary control signal output control lighting, alarm and
other equipment;
⑤ such as user needs, offer high-definition scene grasping fear
function;
⑥ if necessary, and can control centers or other long-distance
voice speaking at the scene.
1.1.2 handling of the data exchange
EDI processing layer is the core of the whole monitoring system,
the core equipment of a number of large-scale digital video
network-management server (central server), database servers, data
storage and forwarding server, alarm server multiple servers. The
graph of a simple description of the data-exchange deal with the
main equipment, the paper will be devoted to follow-up the use of
all equipment and the mutual relations.
Figure 3 handling of the data exchange
Can be seen from the above figure, data exchange layer is mainly
responsible for handling data processing system as a whole. Its
main function is to collect data on the scene of the collected data
can be stored, transmitted and alarm information processing. Major
equipment includes central server, database server, forward /
storage server, display server and alarm servers.
Its main tasks are:
① through the network to all audio and video data at the scene
centralized storage, a specialized data storage servers and disk
arrays for data preservation, to ensure the reliability of data.
② all the audio and video information transmitted data, audio and
video information needs of the site users can be authorized remote
Show at the scene, as well as remote download / playback has been
recorded audio and video data. Generally speaking, the server can
be t
