When security is expressed as an obvious social demand, it is natural and inevitable to adopt the doctrine of taking, learn from and apply relevant technologies to quickly realize the basic elements of security and meet the social security demand. However, there will be some serious problems and deficiencies in this way, such as the high false alarm rate mentioned above. So people began to transform these technologies, form the research direction of security technology, and began to appear unique technologies and products of security. This is the track of the occurrence and development of security technology. The following is a summary. A technology (product) is used for the purpose of safety, so it has the characteristics of function, structure and system operation management. These characteristics are determined by the particularity of safety objectives and the particularity of detection objects of security system. It includes special function and performance requirements, specific architecture (application mode) and special evaluation standards and methods. In order to adapt to these characteristics, the research has become a direction of security technology research. Each direction constitutes the system of security technology and produces special technologies and products of security system. Video monitoring is a technology used for security. Its early application is real-time monitoring, which is a means of rechecking the alarm system, just like the general industrial TV system. Gradually, people began to develop more functions to meet special security requirements. Using video surveillance, people can obtain image information in special environment, so there are special security camera equipment with high sensitivity and suitable for harsh environment, such as day / night conversion, infrared camera and special protective device; The emergence of digital video technology has greatly promoted the application of video surveillance in security system, and produced products and systems specially used in security system, such as digital video recording equipment (DVR), video gateway, remote video surveillance system, etc. These products and application modes are unique to the security system and are produced to meet the security needs; With the in-depth application of digital video, real-time monitoring can no longer meet the needs of security. The automatic analysis, understanding and recognition of images have the functions of detection and early warning, which has become the main research direction of video monitoring technology and the leading technology driving the development of security technology. Therefore, although it can be said that the security system is an important application field of TV technology, it can also be said that video surveillance (especially the above-mentioned special technologies and products) is an important or main part of security technology. The same is true for other technologies. For example, infrared detection technology is the earliest detection means applied in the security field, but the special requirements of security system (authenticity of detection) urge security scientists and technicians to improve and professionalize the detection element structure and signal processing technology, making it a unique intrusion detection equipment and system. In addition to making full use of the foundation provided by other general technologies, it is very important to highlight their own characteristics in the development of an application technology. Everything is established in advance and abandoned without advance. If we highlight the characteristics, we will find the direction, and many topics will be put in front of us. In the past, people paid more attention to emphasizing the characteristics of security application or the importance of the purpose of security application, and hid the security technology with a sense of mystery and particularity. This will neglect to find and establish (form) technical characteristics, thus affecting the development of security technology itself.