Comparison of the hottest analog and digital monit

Comparison between analog and digital monitoring systems

with the rapid development of economic level and science and technology, people have higher and higher requirements for security. In order to deal with all kinds of economic criminal crimes, protect the safety of life and property of the state and the people, and ensure the normal operation of all walks of life and national key departments, the use of high-tech means to prevent and stop crimes has become a consensus in the field of security

from the late 1980s to the mid-1990s, with the introduction of various new security concepts abroad, all walks of life and residential areas have established their own independent closed-circuit television monitoring systems or alarm systems, especially in the banking and financial system, a key national department. The alarm network has been basically formed, which has played a great role in preventing and stopping crime and maintaining social stability

however, the traditional analog video monitoring and alarm system was limited by the technical development level at that time. Most TV monitoring systems can only monitor on site. Although the alarm network can carry out long-distance alarm information transmission, the existing alarm information transmission is simple, unable to transmit video images, unable to timely and accurately understand the situation of the scene, difficult to confirm alarm events, and low system efficiency, Virtually increased the workload of security personnel

in industries with distributed management such as banking and finance, remote monitoring is a necessary means of industry management. In the traditional analog monitoring, the long-distance transmission of images usually adopts special optical cables or microwave transmission, which is easily limited by terrain and lines, and the cost is very high, which is difficult for general users to accept, so it is not easy to promote and apply

at present, in the banking financial system, the existing analog monitoring system can no longer meet the actual application needs. The main reasons are as follows:

★ in the banking system, the existing monitoring system is generally the analog monitoring system installed years ago, its service life has basically expired, and the replacement of monitoring equipment is being considered

★ the clarity of the existing analog monitoring system is not high enough, making it difficult to identify criminals or determine the counting action through the existing analog monitoring system in case of events or errors, such as robbery, money counting errors, etc

★ the existing analog monitoring system has insufficient adaptability in dealing with sudden malignant events. Experienced criminals will destroy the local monitoring system (including video recorders and videotapes) when committing robbery, making it very difficult to trace criminals

★ the existing analog monitoring system is difficult to achieve centralized monitoring, centralized control and centralized data backup. Each business point is independent of each other, and management is very difficult

so how to organically combine the remote image monitoring and alarm system, so that it can not only carry out remote monitoring and image transmission, but also have the function of usually connecting the alarm network, and the cost is reasonable, which can more effectively prevent and combat crime, and improve the security technology to a new level, has become a direction of the current technical prevention work. With the popularization and application of computers and the rapid development of network communication technology and image compression processing technology, digitization and networking is a trend in the field of monitoring. Using the latest computer, communication, image processing technology, and transmitting digital images through lines or other network lines can provide an efficient, feasible and low-cost solution for realizing joint alarm and remote image monitoring

at present, the public has been popularized all over the country. A simple and practical remote monitoring video alarm system can be obtained by connecting the digital remote monitoring video alarm transmission system with general lines. As for the bank financial system with existing network foundation, using its established network system and giving full play to the advantages of computer network, an efficient and reliable video link alarm system can be built, which provides a new high-tech means for bank security and efficient management

II. Analog and digital monitoring a community in Japan is considering accepting the comparison of the project control system

2.1 analog monitoring system

analog monitoring system is an analog series with video matrix, splitter, video recorder as the core, supplemented by other sensors. The traditional analog closed-circuit television monitoring system has its limitations:

first of all, the traditional video signal is analog signal, and the transmission of video signal is usually through coaxial cable. In a short distance, such as meters, the attenuation of video signal is very small; If it exceeds a certain distance, a video amplifier is required to amplify the video signal. Usually, adding a primary amplifier can extend the transmission distance by about 200 meters. However, in engineering, if the video signal is amplified at two levels, the image will be obviously distorted, and in serious cases, the image will be distorted and even appear black stripes. Therefore, the conventional video monitoring system is only suitable for use in a building or a certain range

second, the analog monitoring system can only transmit one video signal on one coaxial cable. If it needs to transmit data signal, control signal or audio signal, it must lay another cable separately. At the same time, with the change and increase of monitoring points and monitored points, additional cables must be laid, which is expensive. Moreover, the image quality of analog monitoring in long-time video recording is poor, which is not conducive to retrieval

third, the advantages of the analog monitoring system can be eliminated by further verification. That is, the image quality can be maintained well within a certain distance. To transmit multiple video and audio signals in a long-distance, high-definition and synchronous manner, the most economical and feasible method is to digitize the analog signals, compress and encode them, and transmit them using public or special communication lines

fourth, from the category of transmission devices, the transmission of video image signals can be divided into two categories: special transmission equipment and computer network transmission. The former includes video transmission equipment connecting private lines or public communication lines, including coaxial cable, line or optical fiber, special video image transmitter and image receiver, microwave and satellite communication equipment, etc. this method was developed in the late 1970s and early 1980s; The latter is to transmit video images through the existing widely distributed computer network and digital multimedia technology. With the rapid popularization of Internet technology in the world, this method is currently developing rapidly. This method will also become a standard of video surveillance system in the future. Mechanical and electrical rotation automatically stops after one week

finally, wired analog video signals can only use special mechanical video recorders and magnetic video tapes. These devices need professional repair and maintenance. The tapes have limited use times, short storage period, easy to magnetize, deform and mildew. One year's data storage and inquiry takes up a lot of space and time. If it is used for a long time, it will bring a heavy burden to customers, and the inquiry and evidence collection is very cumbersome

2.2 digital monitoring system

first of all, compared with analog monitoring, digital monitoring has obvious technical advantages. As a high-tech product that applies computer digital video compression and transmission technology to the field of image monitoring, the working principle of digital monitoring equipment is that the computer converts analog video signals into digital information, and completes the functions of video information acquisition, browsing, transmission, storage and playback. In addition, the computer can also accept various alarm information, output relay control information Automatically execute various alarm linkage operations according to the pre programmed program. The digital monitoring system manages the video monitoring, pan tilt control, image change detection, alarm signal input, relay control signal output, alarm linkage operation and other contents, and has a good human-computer interaction interface. Digital monitoring also supports PSTN, ISDN, DDN, microwave and internal local area access. Any workstation in the network can be authorized to become a sub control station, realizing multi-level sub control, which effectively improves the comprehensive processing ability of emergencies

secondly, the monitoring system makes the alarm layout more reasonable through computer intelligent management. The computer has done the security work in an orderly manner, avoiding any omissions. On the basis of making full use of the characteristics of multimedia, combined with real-time capture, video alarm and other technologies, the prevention work is safer and more thorough, which has produced a great deterrent to criminals and can prevent crimes more effectively. Strict computer monitoring, real-time tracking and recording of each scene of the incident, which is convenient for evidence collection and can fight crime more effectively

finally, the use of digital monitoring system can reduce the intensity of security. The security work seems simple, but it is cumbersome, arduous and significant. The high intelligence of the digital monitoring system further liberates the security personnel from the boring work, and reduces the work intensity while improving the safety; At the same time, it has a powerful function of driving the new output value of relevant industries (excluding medical treatment) by about three times, eliminating the labor of leading safety inspection; Combined with advanced programming theory, a good and friendly operation interface is more conducive to man-machine cooperation and monitoring, and improve safety

2.3 performance comparison between digital monitoring system and analog monitoring system

digital monitoring is the latest and leading leading leading product in the world today. It makes the monitoring field take a big step from analog to digital, which is an irreversible trend and a revolutionary leap in the monitoring field. (end)