CCTV Closed Circuit Television

 It is a video cameras that transmit a video signal to a specific place, on a limited set of monitors

This term is mostly applied to those used for surveillance in areas that may need monitoring such as Institute, casinos, airports, military installations, and stores.

 CCTV, utilizing digital video recorders, (DVRs), with a variety of quality and performance options and extra features (such as motion detection and email alerts).

 More recently, decentralized IP cameras, some equipped with megapixel sensors, support recording directly to network-attached storage devices, or internal flash for completely stand-alone operation.

 

 

 

 

IP cameras

    Internet Protocole Camera (IP cameras).

  IP cameras use the Internet Protocol (IP) used by most Local Area Networks (LANs) to transmit video across data networks in digital form.

 IP can optionally be transmitted across the public internet, allowing users to view their cameras through any internet connection available  through a computer or a phone, this is considered remote access.

 IP video is restricted to within a private network or VPN or can be recorded onto a remote server.

IP cameras Advantage

  • Remote accessibility which allows live video from selected cameras to be viewed from any computer, mobile smartphones and other devices (with sufficient access privileges).

  • Two-way audio via a single network cable allows users to listen to and speak to the subject of the video (e.g. gas station clerk assisting a customer on how to use the pay pumps)

  • The use of a Wi-Fi or wireless network.

  • Distributed intelligence such as video analytics can be placed in the camera itself allowing the camera to analyze images.

  • Transmission of commands for PTZ (pantiltzoom) cameras via a single network.

  • Secure data transmission through encryption and authentication methods such as WPAWPA2TKIPAES.

  • PoE Power over Ethernet to supply power through the ethernet cable and operate without a dedicated power supply.

 

 FRS -Facial recognition system is a computer application for automatically identifying or verifying a person from a digital image or a  video frame from a video source. One of the ways to do this is by comparing selected facial features from the image and a facial database.

The combination of CCTV and facial recognition has been tried as a form of mass surveillance, but has been ineffective because of the low discriminating power of facial recognition technology and the very high number of false positives generated.

 This type of system has been proposed to compare faces at airports and seaports with those of suspected terrorists or other undesirable entrants.

 Computerized monitoring of CCTV images is under development, so that a human CCTV operator does not have to endlessly look at all the screens, allowing an operator to observe many more CCTV cameras.

 

VCA - Video Content Analysis is the capability of automatically analyzing video to detect and determine temporal events not based on a single image. As such, it can be seen as the automated equivalent of the biological visual cortex.

  A system using VCA can recognize changes in the environment and even identify and compare objects in the database using size, speed, and sometimes color. The camera's actions can be programmed based on what it is "seeing". For example; an alarm can be issued if an object has moved in a certain area, or if a painting is missing from a wall, or if a smoke or fire is detected, or if running people are detected, or if fallen people are detected and if someone has spray painted the lens, as well as video loss, lens cover, defocus and other so called camera tampering events.

 VCA analytics can also be used to detect unusual patterns in an environment. The system can be set to detect anomalies in a crowd, for instance a person moving in the opposite direction in airports where passengers are only supposed to walk in one direction out of a plane or in a subway where people are not supposed to exit through the entrances.

VCA can track people on a map by calculating their position from the images. It is then possible to link many cameras and track a person through an entire building or area. This can allow a person to be followed without having to analyze many hours of film. Currently the cameras have difficulty identifying individuals from video alone, but if connected to a key-card system, identities can be established and displayed as a tag over their heads on the video.

Network Video Recorders (NVR)

A Network Video Recorder (NVR) is a software that records video data on the hard disk. Like a DVR, it usually record digitally so the user can  instantly search by time, data and camera. It collect video from IP camera, network video server or DVR over the network. It collect no  analog data input.

All the decisions that need to be made regarding DVRs apply to an NVR.

NVR can be securely positioned anywhere on the network,whereas DRS and VCRs reside where the camera coax terminates.

    

 

 

 

 

Video Surveillance artificial intelligent

  Using computer software programs that analyze the images from video surveillance cameras in order to recognize humans, vehicles or objects.

Security contractors program the software to define restricted areas within the camera's view (such as a fenced off area, a parking lot but not the sidewalk or public street outside the lot) and program for times of day (such as after the close of business) for the property being protected by the camera surveillance. The artificial intelligence ("A.I.") sends an alert if it detects a trespasser breaking the "rule" set that no person is allowed in that area during that time of day.

  The A.I. program functions by using machine vision. Machine vision is a series of algorithms, or mathematical procedures, which work like a flow chart or series of questions to compare the object seen with hundreds of thousands of stored reference images of humans in different postures, angles, positions and movements.

  The A.I. asks itself if the observed object moves like the reference images, whether it is approximately the same size height relative to width, if it has the characteristic two arms and two legs, if it moves with similar speed, and if it is vertical instead of horizontal.

Many other questions are possible, such as the degree to which the object is reflective, the degree to which it is steady or vibrating, and the   smoothness with which it moves.

  Combining all of the values from the various questions, an overall ranking is derived which gives the A.I. the probability that the object is or is not a human. If the value exceeds a limit that is set, then the alert is sent. It is characteristic of such programs that they are self-learning to a degree, learning, for example that humans or vehicles appear bigger in certain portions of the monitored image – those areas near the camera – than in other portions, those being the areas farthest from the camera.