Evolution of analog CCTV systems

Over time, analog CCTV systems have evolved into digital recorders known as DVRs. The acronym is original from the name Digital Video Recorder.

Digital Vídeo Recorder (DVR)

When using a DVR to record the footage from security cameras, there is a conversion of the analog to digital signals before recording and transmission over the local network or Internet.

When doing this conversion from analog to digital, the CCTV system can no longer be considered purely analog, so in fact, it is a hybrid system that uses analog security cameras but with a recorder that has digital (DVR) technology.

Modern analog security cameras

In addition to the evolution of analog CCTV systems to the hybrid version that uses DVRs for digital recording, new technologies have also emerged from analog security cameras that can provide higher resolution and thus better image quality.

These technologies are known as HD-TVI, HT-CVI, and AHD. 

 

Digital CCTV Systems (IPs)

CCTV systems continued to evolve, and so the world's first IP security camera was created to allow the video transmission over long distances through digital networks.

IP cameras are autonomous devices with the ability to communicate on the network directly without the requirement of an intermediate system as it happens in analog systems that are dependent on the VCR or DVR.

An IP camera can record video on an internal memory card and on a digital recorder known as NVR (Network Video Recorder) and still transmit the images over the network or Internet directly.

There are numerous advantages of a digital CCTV system compared to traditional analog, 

Digital CCTV Systems and the Internet

Computer and Internet networks use a protocol called TCP/IP and all devices that need to communicate on the network must use the same protocol, so computers, servers, printers, notebooks, tablets, cell phones, and IP cameras "speak" TCP/IP, so it is possible for an IP camera to communicate on the network easily.

With this ease of communicating in a computer network, an IP camera can be installed in a home or office for example and accessed from anywhere in the world through a private network or the Internet, exactly as shown in the diagram below.

Note in the previous diagram that the IP camera is installed on a local network where there is a router that connects to the Internet and allows recording and monitoring in the other location that is also connected to the Internet.

The IP camera does not need any auxiliary device to communicate on the network, simply connect it and make the correct configuration.

Digital CCTV Systems projects

With the use of digital systems, there are no barriers, because the IP cameras that connect in the network are independent and have embedded intelligence, which allows their use in various situations such as metropolitan, residential and business monitoring.

When installing cameras in a city, it is necessary to transmit images to a central station that can store and monitor them in real time.

In these cases, an IP camera becomes the ideal device to be used as it generates images already in digital (IP) format and can be connected to a fiber optic or wireless radio network to perform transmission to the monitoring station.

Any current metropolitan project is composed of IP cameras with high resolution and video analytics.

Modern metropolitan CCTV projects generally use wireless radio for the transmission of videos to a central monitoring station, and as an IP camera is prepared to connect directly to a wireless transmission system, the installation becomes much easier.

Special intelligent systems for capturing people's faces and vehicle license plates also use IP cameras.