CCTV Security Systems Chennai India

Posted on April 3, 2010, 8:51 am

VIDEO MONITOR Information Portal CCTV closed circuit television (CCTV) CCTV is a collection of video cameras used for video surveillance. CCTV is different from the TV that all equipment is directly connected with cables or wireless transmitters that can not be received by standard television antennae or equipment. The transmission of video signals are only intended to be accessible by the device in its closed circuit dedicated. CCTV is generally used in areas where there is a heightened need for security, such as banks, airports and city centers. CCTV was initially developed as a means of increasing security for banks, but over time it became a profitable way of general video surveillance and home security. A basic system includes the following CCTV, camera, lens and power. recording device, a VCR or DVR. Monitor. Cabling CCTV Cameras CCTV Cameras are available in color, monochrome cameras which have the ability to switch between color and monochrome (day / night CCTV cameras). The surveillance cameras that switch between color and monochrome are intended for low light environments on several occasions. There are 2 reasons for using a surveillance camera that can switch between color and monochrome, monochrome CCTV cameras are much more sensitive to low light environments and monochrome CCTV cameras can also be used with Infrared Light red. When there is sufficient light available, there is the advantage of using a color video camera to record color information, such as the color of a car or person, clothing AA. The primary function of a surveillance camera is to convert the light into a video signal, all cameras require a lens to focus light on an image sensor located directly behind the lens inside the camera cameras. There are two types of image sensor available, a surveillance camera of a CMOS (Complementary Metal-Oxide Semiconductor) image sensor chip and the other most common type that uses a CCD (Charge Coupled Device) image sensor chip. The majority of CCTV cameras and camcorders use a CCD image sensor, while the CMOS imaging sensors are commonly used in webcams, security cameras and home budget camera digital photography. CCD cameras are capable of creating an image resolution much clearer and more. Different types of CCTV cameras are cameras on board, C-mount cameras, IR cameras, IP cameras, zoom cameras, speed dome cameras. All cameras require power, it is usually 12 volts DC, 24 volts or 240 volts AC. CCTV Lenses As mentioned in the section on video surveillance cameras, all cameras require an optical lens. The work aims to limit and focus the light on the image sensor of the camera. A goal can also automatically control the amount of light reaching the image sensor, these lenses are called Auto Iris (AI) and the lenses are usually used outdoors where the light is constantly changing during the day, night and also in varying weather conditions. It is also the use of objective control depth of field of the image, whether for a wide-angle or closed angle image based on the distance to the object in question from the camera monitoring. When mobile speed cameras are used to zoom is usually installed to allow different points of a monitored area to be viewed. Zoom lenses are usually controlled by the CCTV operator. CCTV Recording Devices The recording device receives and stores images from the surveillance camera, time elapsed before VCR, AO and video multiplexers are typically used in video surveillance systems, but because of changing technology DVRs are now more commonly used. Time Lapse VCR, SOA enables CCTV camera images to be stored for varying periods on a single video cassette 3 hours, from lengths of 3 hours to more than 960 hours. The problem with the time elapsed video recorders is that the more they will have to record information unless they can save videos per second, similar to taking a photo of 25 per second for a photo every 4 seconds for example . Digital video recorders use hard drives for storing recorded information and can save however much longer depending on the hard disk size and the codec used. A DVR combines and improves the recording capabilities of a time a VCR and a multiplexer. CCTV Switchers CCTV camera and VCR When there is a requirement for registration of more than one camera and surveillance camera video switch can be used, the cameras are connected to the switch and the switch automatically switches the image being fed screen and video. The disadvantage of using a switch is that if an incident occurs, it is possible that the image of the CCTV camera will change the origin of the incident to be missed. CCTV CCTV video multiplexer video multiplexer is a device that supports multiple video images and place them on a VHS tape, it uses the properties of the PAL signal to save as many images from multiple video surveillance cameras every second as possible. The video information recorded is limited by the amount of CCTV cameras on the system and the length of time the VCR is set to record. CCTV standalone DVR Video A stand alone DVR is specifically designed for CCTV systems. It uses hard disk drives to store video information and an embedded operating system to control the DVR functions, this type of recording device is the most commonly used with existing CCTV systems. CCTV digital video recorders have various settings to allow more video information to be recorded at once using the technology needed such as video motion detection, this means that the camera images from closed circuit television are only recorded information when the image changes, eg a person walking in front of the camera. As mentioned previously, the DVR CCTV integrated multiplexer allows the user to display multiple images on the screen at one time by separating the image. Many DVRs can also be connected to a network or modem to allow remote access. CCTV DVR Comes with high contrast LCD is called Media DVR. DVR CCTV PC based DVR CCTV PC based programs operate much like the CCTV DVR standalone, but to use video capture cards and additional software to perform the operations of the DVR, DVR can these types of be easily upgraded to accept additional cameras by adding more capture cards. As with standalone DVR, AOS, PC based recorders can also be connected to the Internet for remote access to the DVR. CCTV network video servers network video server designed for IP CCTV cameras on WAN or LAN computer networks where each camera has its own unique IP address. CCTV Monitor There are two main types of screen, the monitor called analog CRT (Cathode Ray Tube) and the digital monitor that is commonly used to follow the PC known as TFT (Thin Film Transistor) monitor. There are advantages and disadvantages for both screens, TFT screen uses less space than a CRT. A CRT monitor displays a better picture of the cameras at low and medium resolution of a TFT. For high resolution camera, a TFT can be more cost effective than using a high resolution CRT monitor. CRT monitors are generally designed for systems closed circuit television and are equipped with a composite video input BNC (Bayonet Nut Coupling) sheet. CCTV monitors are also designed for long-term use compared to standard televisions and respond to higher screen resolutions. Developed in the late 1940s, the AM as a miniature version of C-type connector, Bayonet Neil-Concelman (sometimes mistakenly called British Naval Connector or Bayonet Nut Connector). A connector widely used in the television industry closed circuit, usually coaxial cable. Easy to install and reliable with little video signal loss. A rotating ring outside the tube locks the cable to any female connector. All lighting CCTV surveillance cameras must have a degree of light must be able to take a picture, monochrome cameras generally work well in dark environments that cameras CCTV color. Infrared light can also be used with CCTV cameras monochrome. There are different types available or infrared light, light bulbs or LED (Light Emitting Diode) types. Infra red lighting can illuminate areas at different frequencies, although invisible to the naked eye, surveillance cameras can see the light emitted. According to the range of frequencies that the infrared lights, depends on how visible the light of the lamp is to the naked eye. Note, however, not all devices are sensitive enough to pick up all the frequencies of infra red. CCTV Hidden Camera Covert CCTV is the practice of using video cameras in places that are not obvious to those under supervision in the CCTV camera coverage area specific, but it is recommended that there be a reasonable for purposes of covert surveillance and that its main objectives are clearly stated, used only for purposes of crime prevention and are used for longer than expected. Remote CCTV Remote CCTV is the way to access CCTV images on a computer network or standard telephone networks. The software is used on the local PC which provides access to the digital video recorder. CCTV CCTV IP CAMERA IP refers to Internet Protocol Television closed circuit systems use traditional analog CCTV cameras using digital or analog cables that connect to a recording device like a DVR. IP video cameras are designed to plug into any existing wired or wireless computer network TCP / IP, or directly on a broadband connection so that the surveillance camera can be accessed by any computer connected to the network, including on the Internet. Computers are used on the network to store the images of CCTV cameras, but with the flexibility of IP CCTV surveillance cameras could be located on opposite sides of the world. Although IP CCTV cameras can be connected directly to an existing network, bandwidth is always a consideration that the data sent by the surveillance camera is likely to be much larger than the data transferred over existing standard normal business, which if not planned correctly can slow the entire network. CCTV video signal the video signal is known as the information signal on a moving image produced from a video camera, we use a standard video signal called PAL (Phase Alternate Line) there is a color or monochrome video signal that contains 25 pictures or frames per second. A new breed of cameras called IP CCTV Cameras Internet Protocol (CCTV) uses a data signal that includes a series of computer-readable images. These CCTV cameras are typically connected directly to a computer or computer network and accessed by the software to enable live viewing, recording and playback of video images. A format of the motion video is called MPEG (Moving Pictures Experts Group). CCTV Video Transmission video transmission is the way to capture the video signal from the camera to the recording or monitoring device. The transmission can be transmitted by the son or via radio waves. The cable most commonly used for transmission by cable is a coaxial cable RG6. cable network is used more often than the video is able to travel farther than the standard twisted-pair cables coax. Other forms of video transmission cables include fiber optic, microwave transmission and a transmission license free radio. CCTV Resolution Resolution refers to the number of definable parts of the image produced by a horizontal camera, recorded by video or digital video recorder and displayed on the monitor. CCTV equipment manufacturers refer to this as TVL (TV Lines). Minimum 420 TVL is recommended. The TVL of the analog PAL video information is closely relative to the pixels of a digital image. VHS (Video Home System) recorders are capable of recording 300 lines of 240 lines monochrome image or color image, SVHS (Super Video Home System) is capable of recording 400 lines of the monochrome image to 340 lines a color image. The recording device shall be the determining factor when choosing the resolution of a camera as a camera 520 TVL being recorded on a VHS recorder will only record 240 lines out of 520 available lines. Digital Video Recorders (DVR) have the advantage of being able to convert the PAL analog signal into a digital signal at different resolutions, the disadvantage is that the higher the resolution of the recorded image, the larger the digital image file. The conversion of the analog PAL signal to a digital image is done using a codec (compressor-decompressor). CCTV Codec A codec is used to convert an analog video signal to a digital video signal, either using hardware or software. Codec play an important role in digital video recorders, they are not only used to convert the analog signal into a digital signal but also to produce information for the best video quality for small file size. It makes a big difference in the amount of video that can be stored on a hard drive DVR. There are many standards CODEC, those used for video compression that you may encounter are MPEG-2, MPEG-4, JPEG 2000, AVI and H. 264 H. 264 is the latest codec being introduced on the market for CCTV, arising from video conferencing equipment.