How to distinguish between network video and HD-CCTV surveillance cameras

HD-CCTV, developed from the broadcast television system SDI, looks at the system structure: it is an extension of the traditional monitoring model, and the core feature is the closed-circuit structure and the specificity of the transmission medium. It does not sub-pack or compress the video stream output by the camera. Therefore, the transmitted image is not distorted, jittered, and has good real-time performance, which provides the best image for intelligent image analysis of the background of the system.

From the media's publicity, the demand for online video seems to be high. In fact, in terms of technology maturity and image quality, HD-CCTV is advantageous, but it is limited by the transmission bandwidth and there is a certain limit in the scope of application. The network video is currently mainly used in the networking of video surveillance systems, and the focus is also on solving the problems of interconnection between networks, interoperability between systems, and interworking (decoding) of data, etc. The program.

This structure facilitates the conversion of the system from standard definition to high definition and from analog to digital smoothing. However, smooth conversion does not mean full compatibility. The so-called “plug in and use” is not correct, and it is considered to be exactly the same point of view as analog video. It is also wrong. The coaxial cable or BNC connector used in the system is completely different in performance from the products in the analog CCTV system.

The data flow of the SDI system is not a normal video compression coded signal but a digital stream in which a parallel video component signal is converted to a serial sequential system signal. Since it does not perform compression processing, the data rate is high. Normally, SDI is a 270M system while HD-SDI is a 1.5G system. Therefore, the transmission distance is greatly limited, but with the advancement and application of optical communication technology, this point will be significantly improved, and the application range of the HD-CCTV method will also continue to expand.

Network video, digital video system using network platform. It is characterized by openness, autonomous system generation, and easy system expansion and upgrade. At present, there are a lot of applications for video surveillance systems based on network transmission, but compared with analog video surveillance systems, there is no advantage in image quality.