Analog
Video Intercom System: all use analog technology to transmit audio and video signals. Generally, bus technology is used to transmit signals over common lines. This technical system has the following major problems:
1, poor anti-interference ability. Due to interference, there are often no signals or images and sounds are not clear;
2, limited transmission distance. Analog signals are apt to attenuate and distort. Amplifiers need to be added when the distance is long, and the increase in network costs is not to be said, nor can they ensure the reproducibility of signals.
3, Bus line technology is particularly busy. Because only two points can be called on the same bus;
4, a single function. In addition to supporting simple information distribution functions, it is mainly limited to functions such as calling and unlocking, and the use rate of equipment is low.
5. The limitation of product upgrade or expansion is large;
6. It is difficult to integrate with other weak electronic systems. The industry lacks standards. Products of different manufacturers cannot be interconnected and it is difficult to integrate with other weak electronic systems.
7, large-scale wiring projects, high service costs, can not be integrated into the community integrated network.
The insufficiency of the analog video
Intercom System not only seriously affects the stability and reliability of the system, but also fails to meet the different requirements of different brands of digital video intercom systems: fully using TCP/IP technology All terminal equipments such as indoor units, door machines, wall machines, and management machines adopt TCP/IP technology, combined with the latest digital audio and video compression technology, DSP technology, streaming media, and IPV6 network transmission technology. Its main advantages are as follows:
1. Compared with the analog video intercom system for bus transmission, the digital video intercom system is much more convenient for wiring and installation and debugging. Because the digital video intercom system uses the TCP/IP method to transmit signals such as sound, data, and video images, a single network cable can solve all problems, greatly simplifying the wiring project, and making the installation and debugging of the building intercom system changeable. It is simple and the construction period is greatly shortened.
2. When all signals are digitized, it is easy to meet networking requirements. Digital video intercom system indoor unit like a small computer, both high-performance CPU, DSP digital processing chip, powerful data processing capabilities make networking powerful, for integration with other security subsystem It's convenient.
3, IP networking has strong scalability, it can not only achieve video intercom, but also can achieve multimedia messaging, broadcast, security alarm, smart home, IP video phone, VOD on-demand, video surveillance, and value-added services Other functions. If you access the internet, you can configure, monitor, remotely upgrade, and remotely read the meter on any terminal (visual walkie-talkie) on the Internet. It can not only meet the needs of traditional video intercom applications, but also provide security alarm, smart home control and other functions, and become the core hub of the “digital home”.
4. Now that the development scale of the community is getting bigger and bigger, through video amplifiers and other solutions, it can also extend the transmission distance to a few kilometers, but the cost is too high. The video intercom system based on the TCP/IP method has no distance limitation and can realize low-cost long-distance transmission.
For the moment, digital video intercom is in an accelerated period of development, both in the market and in technology, and is increasingly becoming an important role for digital homes. Its own three major elements: video compression, voice processing, network transmission, making digital video intercom and other home multimedia products integration. As the demand for digital products in the market is becoming more and more prosperous, digital video intercom has become a general trend. Many manufacturers have also seen the advantages of digital video intercom products, and they all want to catch this "golden train!" Domestic intercom manufacturers also focused their attention on this earlier. Some manufacturers have already produced and sold digital video intercom products. Some manufacturers are still in the research and development stage. As a result, the market for digital visual intercom products is relatively mixed, and half-digital and fake digital products are also full of them, making digital video intercom products in the hearts of users greatly reduced, still taking a wait-and-see attitude. So, how to identify the true and false digital visual system?
1, first of all to examine whether the use of standard TCP / IP protocol, whether the audio and video signals transmitted through the encoding and compression of digital signals.
2, to see whether the middle device, networked devices are common. At present, some use dedicated switches, and some rename the switch to switches, etc. These need to be noted. In general, the true networking middleware can be purchased directly from the market. If it can only be purchased from the intercom supplier, it is certainly not a true digital product. The real digital product is standard and universal.
3, look at the interface. When purchasing the product, we must carefully observe the interface of the door machine, the center management machine, the indoor unit and the wall machine to see if it adopts the RJ-45 interface. If it is not the RJ-45 standard interface, it is certainly not a digital intercom equipment.
For a long time, there is a fixed concept in people's minds: “New technologies mean high prices, and new products are definitely more expensive than traditional products.” Well, as the leading technology of digital intercom systems, it must be better than traditional analog visual pairs. Speaking of high system cost and cost? In fact, from the point of view of installation, commissioning, and wiring, the use of TCP/IP transmission methods requires a small investment. At the same time, the construction period is shortened, personnel expenses are saved, wire and labor costs are reduced, value-added services can be brought, and maintenance is easy. Therefore, the key lies in how you choose!
