Full Form of CCTV:- Video surveillance is a process carried out with the use of optoelectronic devices designed for visual control or automatic image analysis (automatic recognition of faces, state numbers). CCTV is a closed-circuit television system.
History of CCTV
The forerunner of video surveillance can be considered photographing in order to ensure security. In 1913, the modern photographic observation system was used in Holloway Prison. The guards made unofficial photographs of prisoners from long distances.
The reason for such actions was the refusal to take photographs of a dossier of 18 political activists arrested for their brutal actions during demonstrations. Every time they noticed a camera aimed at them, they tried to do everything so that the result of photographing was useless.
They covered their faces with their hands, made faces, refused to stand still. The use of spoiled photos for further identification was useless. These extremists were called suffragists.
The world’s first video surveillance system was created in Germany by Siemens in 1942 to monitor the testing of V-2 missiles at the Peenemunde test site. The main developer of the system was Walter Bruch, who later, in 1963, led the development of the PAL system.
Vericon, released in the United States in 1949, is considered the first commercial video surveillance system. The main advantage of the system was the use of wires instead of radio waves, and as a result, there is no need to obtain permits.
It should be noted that in 1949 George Orwell’s science fiction novel “1984” was published, in which the author described the massive use of video surveillance long before its distribution.
In 1956, in Hamburg (Germany), the police tested an outdoor video surveillance system called the “Zauberspiegel” (“magic mirror”). The system was presented to the press during the conference.
The policeman watched a monitor on the traffic on the street and switched traffic lights with the push of a button. In 1959, the use of a video surveillance system to monitor increased street traffic began in Hanover and Munich. In 1960, the police of Frankfurt have Main put into operation the first automatic system for photographing traffic offenses at traffic lights.
In addition to the situation on the roads, automatic cameras monitored the situation in crowded places. In 1965, the Munich traffic surveillance system was expanded to 14 cameras, each of which had the function of planning.
Despite the fact that the Germans were the first to use television surveillance systems. The UK was the first country to begin an experiment in installing permanently fixed cameras in public places for security. In July 1960, the London police set up two temporary cells in Trafalgar Square to observe the crowd, which came to observe the official visit of the Thai royal family.
In September 1968, video surveillance was installed on the busiest streets in Olean, New York, in order to protect the rule of law. Installed cameras sent images to the police department 24 hours a day. They had a mechanism to turn right and left on the timer, capturing a large space in the surrounding streets, and really allowed to prevent crime.
It took 2 years and 1.4 million dollars at the rate of 1968 to design and deploy a security television system for 8 cameras. News about the new system quickly spread. During the year after the installation, 160 police department heads from across the country came to Olean. To familiarize themselves with the principle of operation and the possibilities of video surveillance.
Early video surveillance systems allowed only to view the image from the cameras. And recording was possible only in manual mode by the operator’s command. The continuous recording appeared only in the 1970s with the development of video recording technology.
In the 1980s, digital signal processing began to be actively implemented in video surveillance systems. CCD arrays have become actively used in cameras instead of cathode-ray tubes, which has led to a reduction in the size of surveillance cameras. Begin to produce color surveillance cameras.
May 10, 1997, in Brighton (United Kingdom), the first protests against mass video surveillance took place. More than 200 people participated in the protests. They were not only but also provocations.
Such as the dramatization of the fights in front of the cameras, the stealing of their own cars, the imitation of the drug trade. Also, activists blocked the cameras with balloons and posted warnings about video surveillance in the toilets and changing rooms. Several dozen cameras were damaged. Police arrested three people who damaged cells in the city center.
In the late 1990s, fully digital video surveillance systems, in particular, IP and SDI, appeared. And began to gain popularity, while analog systems began recording the signal on digital media. The cameras also began to use cheaper than CCD, CMOS matrix.
In 1998, a face recognition system was first installed in Newham, London. In the 2000s, facial recognition systems allow you to identify a person’s face with an accuracy of at least 80%.
At the moment, the most widely used camcorders based on CCD matrices. In most cases, use short-focus lenses such as fix-focus that do not require automatic control of exposure. The main manufacturers of matrices – Sony, Sharp, Panasonic, Samsung, LG, Hynix. Their use made it possible to create affordable and high-quality products of wide application.
Usually, the difference between cameras based on matrices from different manifests itself in difficult lighting conditions. In the line of each manufacturer, there are both cheap and standard matrix parameters, and high resolution and/or high sensitivity matrices.
According to the design features of the camera can be divided into the following types:
- The modular video camera is a packageless device in the form of a single-layer printed circuit board. The most common size is 32 × 32 and is intended for installation in thermocouples, hemispheres, etc.
- Mini -video camera – video cameras in square or cylindrical cases, usually used as a finished product for indoor installation.
- Case video camera – the most common form factor devices, also called the camera standard design or Box camera. The prevailing number of devices of this type is supplied without a lens. And a mounting bracket, leaving the consumer with the most flexible configuration of the final device.
- Dome camera: Dome camera – the body is a hemisphere or a ball attached to the base. It can be made of both plastic and metal.
- Controlled (rotary or high-speed video cameras) – a combined device consisting of a camera, zoom lens and rotator. The most widespread so-called integrated cameras, made in the form of a dome.
- Gyro video cameras: They are video cameras used on moving objects in order to obtain a stabilized image.
According to the type of output signal, the video camera is divided into analog and digital. Most digital cameras transmit a signal over a standard computer network such as Ethernet — the so-called IP cameras.
According to the method of data transmission camcorders are divided into wired and wireless. The latter is composed of a transmitting device and antenna. Wireless, including digital IP-cameras, transmitting the image via Wi-Fi radio network – the so-called Wi-Fi-video cameras.
Lens – a device designed to focus the light flux on the matrix of a video camera. Lenses are divided into:
- monofocal lenses with a fixed focal length;
- variofocal (zoom) lenses with a variable focal length, manually or remotely variable.
By way of controlling aperture, lenses are divided into fixed-aperture lenses, with Direct Drive aperture control, and with Video Drive aperture control.
For various operating conditions, modular video cameras are placed in various types of enclosures. For example, a dome case (traditional for indoor cameras), thermocases (case protected from rain and low temperatures. Intended for outdoor cameras), anti-vandal housing for outdoor and indoor installation), etc.
Image Output Means
- Serial video switcher (Switcher) – a device for sequential display of images from cameras on 1 monitor. (Obsolete with the advent of digital recording devices.)
- Quadrator – a device for simultaneously displaying images from cameras (usually 4 or 8) on 1 monitor. (Obsolete with the advent of digital recording devices.)
- A multiplexer is a device for simultaneously displaying images from cameras (usually 4/8 or 16) onto 1 monitor. And generating a sequence of images from all cameras for recording on an analog tape recorder. (Obsolete with the advent of digital recording devices.)
- Matrix video switcher (Matrix switcher) – a device for simultaneous display of images from any of the cameras in the system to any monitor in the system. A much more complex and efficient device than a conventional video switcher.
Image Recording Devices
- VCRs are tape recorders. As a standard, up to 24 hours of video can be recorded on an E-180 tape, with reduced requirements for recording speeds of up to 960 hours. Virtually out of use.
- Digital recorders are modern hard disk recorders (HDDs). They are divided into video servers (based either on a regular PC running Windows or Linux (with a dedicated video capture card when using analog cameras). And video recording and processing software, or on a specially assembled specialized computer that is the core of a large security system) and standalone DVRs ( DVR, non-PC or Stand-alone).
- Other specialized recorders – various types of devices are used to solve individual video surveillance tasks. For example, for recording and storing information from cameras of a video surveillance system installed. Among other devices, an explosion-proof flash- type memory is used.
Also, many IP cameras have a memory card slot to which they can record. This makes the camera a self-sufficient means of video and is also used for recording backup. For example, in case of failure of the main image recording device.
Video and audio door phones
Devices for organizing access control to premises with video recording and/or audio recording.
Thermal imagers – a device for monitoring the temperature distribution of the surface under study. For example, to detect a person in the dark by the day of its thermal radiation.
Automatic cameras – are used to enhance the capabilities of video surveillance systems.
Microphones – used for simultaneous video and sound. In some cases, a different number of cameras and microphones are used – asynchronous video surveillance and audio monitoring systems.
For the organization of video surveillance, a wide range of additional equipment is used: IR illuminators, modulators, amplifiers, etc.
Video Surveillance System
A video surveillance system is a software and hardware complex (video cameras, lenses, monitors, recorders, and other equipment) designed for organizing video monitoring both at local and geographically distributed objects. The functions of video surveillance include not only protection against criminals. But also the observation of employees, visitors in the office, in a warehouse or in a store, control of activity in any room.
Thus, the video surveillance system provides:
- visual monitoring of the situation at the protected object – providing information on the observation post in real time;
- recording video information on a digital video recorder that allows you to document events occurring at the facility;
- performing the functions of burglar alarm through motion detectors of video cameras or external security sensors. And the awareness of the system operator about the occurrence of an alarm in the controlled area.
Security cameras can be of various shapes and types.
Video surveillance in transport
Video surveillance in buses and fixed-route taxis
- recording of crimes in salons;
- control actions and driver time.
- The solution is implemented through the organization of video on each vehicle. After the vehicle arrives at the park, information from local video recording devices is transmitted to the archive video servers of the park.
Video surveillance in your car
Since 2007, a widespread growth has begun in the use of car DVRs in private cars. Digital car DVR with a video camera produces a continuous recording of the traffic situation. The recording of the DVR is taken as evidence in court and helps to prove innocence or to find the culprit responsible for the accident.
Entertainment and shopping facilities
The main task of video surveillance in a casino is to ensure the preservation of the company’s property. The duties of the operator also include tracking unfair personnel, fraudsters, monitoring of cases of theft. Ideally, the operator knows all the casino rules, basic strategies and account systems, monitors the appearance and actions of the staff, the behavior of the players, based on body language.
At large shopping sites, video surveillance is used for the following purposes:
- Opposition to the theft of visitors. Through the interaction of the CCTV operator with the shop detectives (security officers in the trading room under the guise of buyers). And the physical security team (employees of the private security company or the uniformed security service in the uniform). The tacit visual surveillance of suspicious persons through the store is carried out.
- Control over store personnel. In the absence of an access control system for magnetic keys, video surveillance helps to monitor labor discipline (time of arrival and departure of employees). The cameras also placed in the warehouse and office premises help the security service in analyzing business losses that occur in the logistics department:
- Investigation of non-inventory documents (when the goods were not actually brought, but the person in charge took it fictitiously)
- Investigation of the re-grading of the goods accepted and shipped
- Investigation of the facts of damage to the goods when moving through warehouses (incompetence or negligence of staff)
- Ensuring overall security. Since the video surveillance operator, with well-chosen placement and type of cameras, controls almost the entire hall. He can coordinate via radio station the arrival of security officers at the scene of the fire, committing unlawful actions. And providing first-aid to the visitor who felt bad. Viewing archives helps to investigate accidents with personnel (warehouses, as a rule, are mechanized with lifting and loading equipment, injuries and similar emergencies are not uncommon there)
- Since large shopping complexes are the place of crime not only for the enterprise itself. But also for visitors, the presence of a video surveillance network with data archiving helps to investigate. And in some cases prevent car thefts from parking lots, pickpockets and corsets. Often law enforcement officers turn to the Security Stores with a request to provide archival video data when such crimes occur in the CCTV field of view.
At the moment, video surveillance systems are installed in half of the county’s offices. Fixing events in the office serves to ensure the safety of employees, prevent petty theft, identify unfair employees, as well as limit the possibility of “leakage” of proprietary information.
The legality of video surveillance
The lawfulness of video surveillance is determined and regulated by the relevant laws and regulations of the country in whose territory undisclosed and hidden video surveillance will be installed. In almost all cases, the following principle applies.
The legality of video surveillance depends on whether it violates human rights and whether you have permission to carry out this activity from people whom it directly affects. Toilets and recreation areas are among the places in which the installation of video surveillance is unacceptable. Places, where cameras are installed, should be equipped with special warning signs.
For example, Video surveillance is being conducted. The corresponding changes should also be reflected in the employee’s employment contract, where the following points should be specified:
- view a video archive has the right to a limited circle of persons, mainly the head and security staff;
- the above employees must be notified of the responsibility for disclosing and using the personal data of employees;
- recordings from surveillance cameras cannot be used to stimulate employee behavior, or for educational purposes
A typical home video surveillance system includes a video camera that is connected via cable or wireless to a home local network. The kit also includes software for remote monitoring, video recording, as well as for managing recorded content. The network is built on the basis of one or several IP cameras.
High Altitude Television
Video surveillance of places of mass gathering of people, places of cultural and sports events, special operations and ground objects. These are the tasks of closed-circuit high-rise television systems. Often, information obtained from video cameras is crucial for rapid response in emergency situations. High-altitude television is also used for rescue and search operations.
Characteristics and units used in video surveillance systems
The sensitivity of the video camera is characterized by a minimum aperture diaphragm (maximum F-number), giving the video signal amplitude 1 on a test chart. The illumination which 2000lk, with a color temperature of 3200 to K. camcorder sensitivity, clearly defined in the broadcast in-circuit television is often misunderstood. It usually confused with minimal illumination.
Minimum illumination (in the characteristics of video cameras, this parameter is often referred to as sensitivity) is the smallest illumination on the object. At which the video camera gives a recognizable signal, expressed in lux on the object.
A number of manufacturers use the term recognizable signal in a broad sense and do not indicate the signal level at the output of a video camera. This level can even be 10%, which, with the automatic gain control (AGC) turned on, will seem to be significantly higher.
The dynamic range of a CCD video camera is defined as the maximum signal relative to the RMS background value of the exposure. That the ratio of dark and bright objects within a single scene. The higher this ratio, the darker elements are visible on the bright general background of the frame.
The resolution of a video camera is the maximum number of lines that fit in one frame of the monitor ( TVL – television lines, from the English. Television Lines, TVL). The horizontal resolution is usually indicated; the vertical resolution is 3/4 of the horizontal resolution.
The resolution of video processing and display devices is measured, as a rule, in pixels. This is the ability of the device to observe, fix and (or) display adjacent points of the object’s graphic image separately. Measured by the number of separately displayed points per inch of the frame surface. The first number is the number of dots horizontally, the second is vertical. Sometimes it is measured in CIF.
The signal-to-noise ratio is the excess of the signal level above the noise level at minimum illumination, measured in dB and depends on the quality of the CCD of the video camera. On the screen, a noisy image looks like grain or snow, and short colored stripes or flashes appear in the color image.
Recording speed (playback or viewing) – Frame frequency – the number of frames that a video system records (plays or transmits) per second. Sometimes manufacturers use pps – the number of half-fields displayed by the video system per second.
- Continuous recording is a constant round-the-clock video recording,
- Scheduled Recording – recording at a specific time of day,
- Alarm recording – recording starts when a certain signal arrives,
- Motion Detection Recording – recording is performed only during image modification,
- Emergency or manual recording – recording starts at the operator’s command (when a button is pressed).
Dual streaming is a property of IP video cameras and video encoding devices to provide two video streams of different quality for each video channel. The high-resolution stream is used for archiving and displaying in full-screen mode. The low-resolution stream is used to display in multi-screen mode. In general, it is possible to provide more than two streams.
Integrated Security Systems
Currently, video surveillance systems have begun to provide not only the standard playback and recording capabilities of the video stream from the camera. They allow you to automatically solve many problems without human intervention. Ranging from simple motion detection in the field of observation, ending with high-precision counting of passing cars or past people.
Integrated security systems include a set of organizational and technical measures to protect objects from any unauthorized entry to the object. From the unauthorized collection of confidential information, from theft, vandalism or sabotage.
They reduce business risks and the likelihood of business continuity. Integrated systems can and should be used in cases of the occurrence of information security events. Use in court proceedings, corporate investigations, changes in the management of the company’s information security system.
Interconnected elements of integrated security systems include:
- video surveillance systems, remote video surveillance systems, wireless, distributed and centralized video surveillance systems;
- audio monitoring, including remote audio monitoring;
- access control systems (ACS), remote access control and management systems (ACS), working time control systems, metering of information about the location of employees at the facility;
- number recognition systems in parking lots;
- protection by technical means of premises and objects from unauthorized listening, viewing. And collecting information (protection from listening using radio equipment, radio bookmarks, radio scanners, using infrared scanners, acoustic and vibro-acoustic listening devices, monitoring telephone lines, cable television lines, power grids, etc.) ;
- anti-tampering equipment during outdoor negotiations;
- protection against radio fuzes (radio-controlled explosive devices);
- radiation safety control to protect against radiation terror;
- various systems of comprehensive security and fire alarm systems (fire and security alarm systems, fire alarm systems, fire alarm systems, fire alarm systems);
- installation of barriers, turnstiles, sluice chambers, etc .;
- a complex of means for protection against violent invasion or an attack of gangster groups.
Integrated security systems can be built on different remote sites with a common control center.