Video control systems are used to control and monitor the main sections of the building and areas where there is less access to the viewing in those areas. Today, CCTV systems are widely used in industrial and administrative centers to fully monitor physical environments and monitor the performance of employees and workers in order to better control and manage more efficiently and efficiently.
Evolution of video surveillance systems:
Part of the benefits of the CCTV system
Capture images with maximum image resolution
Save and review images with image compression format
Control and monitoring system and network communications
Integration with BMS system
In this section, we will briefly review the evolution of video surveillance systems.
First generation Analog CCTV system using VCR:
Analog video cassette recorders (VCRs) with CCTV were used in these systems. Which in fact includes a completely analog and Yamolta system of splitter between the camera and the quad. These systems allow the VCR to be recorded, but this can be done at a lower pace of several cameras on the package. To see the screenshot of the monitor The analogue was used, as shown below under the general arrangement of the system.

The problems of this generation can be summarized as follows:
● Limit distance and low image quality on coaxial cables
● Restrictions on the storage of stored images
● Unable to view images from multiple locations

Second Generation Analog CCTV System Using DVR:
In this system, the video is replaced by a hard drive. Therefore, the video information needs to be digitized first and compressed and then stored on the hard drive.
The following is the second-generation makeup of video surveillance systems.

Third-generation Analog CCTV systems using a network DVR:
This system is in fact a semi-digital system with a digital and compressed port, an Ethernet DVR. When images can be sent internally to a remote computer on a computer network, some systems can also display images Saved and display live images. Some late, however, can only playback information that is stored. Especially to see the Client, in addition, some systems require images. But some other standard browsers use it.
One of the advantages and disadvantages of this generation is the following:
benefits:
Digital image storage capability
Search pictures from around the world
Difficulties:
Limit distance and low quality image on coaxial cables