History of video surveillance: from glass tubes to artificial intelligence, part 3
World under surveillance
The next stage in the history of video surveillance systems began with the invention of household video recorders. The price of recording devices fell greatly, VCRs began to appear in regular houses, and not just in large institutions. In addition to this, the rapid spread of CCTV systems began. Cameras appeared in stores, educational institutions and government agencies. These changes turned out to be especially important in the judicial practice of the United States, because now the video cassette with the recorded fact of the crime became the indisputable evidence.
Engineers managed to achieve significant miniaturization in the creation of new video cameras. They were no longer based on a cathode ray tube (the heir to that same Zworykin iconoscope), but a CCD matrix. CCD (charge-coupled device) is a silicon-based analog integrated circuit. The first cameras with CCD matrix had low resolution, but their photosensitivity was several times better than their counterparts with CRT.
The next jump in the development of video surveillance occurred in the nineties. By that time, fully digital broadcast and video recording systems had appeared. The size of cameras and VHS players became even smaller, and the devices themselves were even cheaper. Various CCTV systems were already recording the footage on drives, and recording could be carried out continuously. If the storage space ran out, the system automatically deleted the old clips, that is, recorded what was happening “in a circle.”
In 1996, Axis introduced the first IP camera to transmit a signal through an Ethernet cable. Initially, the device was not widespread, but over the years its popularity had only grown. Gradually, megapixel cameras began to appear on the market, their resolution was several times higher than old video surveillance devices. Finally, in 2004, it was already possible to find 2-megapixel video cameras on store shelves.
Further — more: CCTV systems received many sensors that reacted to movement and even heat. Computer users got web-cameras for communication on the Internet. Large companies like Samsung, Sony and Panasonic joined the technology race, they took away the lion’s share of the market from all other manufacturers.