Glossary

A feature of cameras that  enhances videos of low lights to maintain the output video signal strength. More Detail.

The unit of measure for the rate of electrical current flow characterized by the symbols l (in Ohm's law formulas) and A. One ampere is the current flowing through one ohm of resistance at one volt potential.   More Detail.

The (Camera) lens opening that controls the amount of light that reaches the image sensor. Aperture is expressed as F-stop, e.g. F2.8 or f/2.8. The smaller the F-stop number (or f/value), the larger the lens opening (aperture).   More Detail.

ATSC is a set of standards developed by the Advanced Television Systems Committee for digital television transmission over terrestrial, cable, and satellite networks.

The ATSC standard was developed in the early 1990s by the Grand Alliance, a consortium of electronics and telecommunications companies that assembled to develop a specification for what is now known as HDTV. ATSC formats also include standard-definition formats, although initially only HDTV services were launched in the digital format. More Detail.

A feature of cameras that  automatically adjusts to varying light conditions to maintain the correct white balance on the image. Proper camera white balance has to take into account the "color temperature" of a light source, which refers to the relative warmth or coolness of white light. For more detail, click here More Detail.

AWG is the U.S. standard measuring gauge for certain conductors, including copper.  The higher the AWG number the thinner the wire.  This measure stems from the fact that the original measurement represented the number of times the wire was run through a wire machine which thus reduced the diameter of the wire. More Detail.

The rate at which data is transferred. Named after Maurice Emile Baud.  The Baud rate is equivalent to bits per second in cases where each data event represents exactly 1 bit. To communicate, the baud rates of the equipment must be set the same. Note the baud rate and bit rate in a system can be different. More Detail.

The term bit rate is a synonym for data transfer rate. Bps = Bytes per second, bps = bits per second.  The digital equivalent of bandwidth, bit rate is measured in bits per second.  It is used to express the rate at which the compressed bit stream is transmitted.  The higher the bit rate, the more information that can be carried. More Detail.

Cameras with BLC feature will adjust the brightness level of the image to compensate for the bright background so that more detail of the dark objects can be seen. For an example, when a camera is directed toward a door, the bright light from outside will normally make the overall image too bright to show detail on a subject backing to the door. BLC will compensate for the bright background so foreground objects are not silhouetted.

BNC (Bayonet Neill-Concelman) connector is a type of RF connector used for terminating coaxial cable. It is used for professional video connections. It is an alternative to the RCA connector. See also RCA Connector More Detail.

Cine mount.  The first standard for CCTV lens screw mounting.  It is defined with the thread of 1''(25.4 mm) in diameter and 32 threads/inch, and the back flange-to-CCD distance of 17.526 mm (0.69'').  The C-mount description applies to both lenses and cameras. 

CS Mount (Cine Short Mount) is the newer standard for camera lens mounting. It uses the same physical thread as the C-mount, but the back flange-to-CCD distance is reduced to 12.5 mm.

C-mount lenses can be put on both, C-mount and CS-mount cameras, but must use a C-moun adaptor when used on a CS-mount camera. More Detail.

CCD and CMOS are two main types of technology in current security cameras. CCDs containing grids of pixels are used in Digital camera, Image scanner and video cameras as light-sensing devices.

CCDs boast higher sensitivity, and higher dynamic range than CMOS sensors  while CMOS offers lower product cost and lower power consumption.  More Detail.

Committée Consultatif International des Radiocommuniqué, which is the European standardization body that has set the standards for television in Europe.  It was initially monochrome; therefore, today the term CCIR is usually used to refer to monochrome cameras that are used in PAL countries. More Detail.

A system in which the circuit is closed and all the elements are directly connected. The most widely applications of CCTV are in the security industry.  More Detail.

CIF is part of the ITU H.261 videoconferencing standard. It specifies a data rate of 30 frames per second (fps), with each frame containing 288 lines and 352 pixels per line. It is a format used to standardise the horizontal and vertical resolutions in pixels of in video signals. A related standard, QCIF (Quarter CIF), transfers one fourth the amount of data.  More Detail.

Complementary-symmetry/Metal-Oxide Semiconductor. CMOS image sensors which use the ASP (Active Pixel Sensor) technology, are one of the two major types of image sensors used in security cameras. The other is CCD image sensors 

Comparing to CCDs, CMOS sensors are cheaper to make and consume less power, but they are more prone to noise.  More Detail.

Coaxial cable is the most common type of cable used for transmitting a video signal through copper wire. This type of wiring has a coaxial cross-section where an outer shielding protects the actual interior signal conductor from electromagnetic interference. In the CCTV industry, the term "coax" usually refers to RG-59 cable with BNC-type plug ends.  More Detail.

A CODEC is a device or software that compresses and/or decompresses digital signals. It is used for converting audio/video signals from analog to digital and vise vesa during the process of data transmission and storage. Each data format such MP4, AVI, etc. needs its own CODEC. More Detail.

Composite video is the format of an analog television (picture only) signal before it is combined with a sound signal and modulated onto an RF carrier. In contrast to component video (YPbPr) it contains all required video information, including colors in a single line-level signal. Like component video, composite-video cables do not carry audio and are often paired with audio cables.Composite video is often designated by the CVBS initialism, meaning "Composite Video, Blanking, and Sync." More Detail.

Hole Accumulation Diode is a patented technique of the Sony Corporation to reduce electronic noise in a CCD or CMOS imaging sensor by reducing the so-called "dark" current that occur in the absence of light falling on the imager, resulting in noise reduction and enhanced image quality.

The "hole" refers to places in a semiconductor where an electron has been dislodged, thus creating a positive charge. These "holes" or positive charges can be created by heat or imperfections in the creation of the imaging chip. The "holes" are accumulated, or trapped, in a separate semiconductor layer that acts as a diode that prevents them from returning or creating noise.

"HAD" technology suppresses the fixed pattern noise that results from "dark" current that occurs regardless of the amount of absorbed light. By fabricating a hole-accumulation layer below the surface of the CCD, "dark" current can be suppressed at the source. More Detail

One of the three characteristics of video picture, the other two are saturation and luminance. Hue defines color on the basis of its position in the spectrum. More Detail

IP followed by two digits and an optional letter. As defined in international standard International Electrotechnical Commission" IEC 60529, it classifies the degrees of protection provided against the intrusion of solid objects (including body parts like hands and fingers), dust, accidental contact, and water in Electrical enclosures. The standard aims to provide users more detailed information than vague marketing terms such as waterproof.

The digits (characteristic numerals) indicate conformity with the conditions summarized in the tables below. Where there is no protection rating with regard to one of the criteria, the digit is replaced with the letter X. More Detail.

A Local Area Network (LAN) is a computer network covering a small local area, like a home, office, or small group of buildings such as a home, office, or college.

The mostly widely used term "Internet" refers to the global network that consists of all small computer networks, of which LAN is one type of them. LANs are connected together by WANs (Wide Area Networks).

The defining characteristics of LANs in contrast to WANs (wide area networks) are: their much higher data rates; smaller geographic range; and that they do not require leased telecommunication lines. See also Internet, WAN. More Detail

Luminance defines the luminous intensity of a video signal: brightness and contrast. A colour video picture contains two components, luminance - Y (brightness and contrast) and Chrominance - C (hue and saturation). It is normally measured by LUX. More Detail

A megapixel (MP or Mpx) is one million pixels, and is a term used not only for the number of pixels in an image, but also to express the number of image sensor elements of digital cameras or the number of display elements of digital displays. For example, a camera with an array of 2048×1536 sensor elements is commonly said to have "3.1 megapixels" (2048 × 1536 = 3,145,728). The megapixel count is often used as a figure of merit, though there are other figures that determine camera quality.Digital cameras use photosensitive electronics, either charge-coupled device (CCD) or complementary metal–oxide–semiconductor (CMOS) image sensors, consisting of a large number of single sensor elements, each of which records a measured intensity level. In most digital cameras, the sensor array is covered with a patterned color filter mosaic having red, green, and blue regions in the Bayer filter arrangement, so that each sensor element can record the intensity of a single primary color of light. The camera interpolates the color information of neighboring sensor elements, through a process called demosaicing, to create the final image. These sensor elements are often called "pixels", even though they only record 1 channel (only red, or green, or blue) of the final color image. Thus, two of the three color channels for each sensor must be interpolated and a so-called N-megapixel camera that produces an N-megapixel image provides only one-third of the information that an image of the same size could get from a scanner. Thus, certain color contrasts may look fuzzier than others, depending on the allocation of the primary colors (green has twice as many elements as red or blue in the Bayer arrangement). More Detail.  

Multiplexer  is a video switching device that accepts video input from multiple cameras and converts them to all display on one monitor and / or video recorder, similar to a quad video processor. However, a multiplexer is far more advanced than a simple quad processor. Video multiplexers use time division multiplexing, meaning that a full frame of video from each camera is recorded every few seconds. While multiplexed video does not achieve true realtime display or recording (there is a slight drag to the images on playback), multiplexers do offer the capability to change between a view of several cameras and a solid closeup view of only a single camera's view on playback of recorded video. When using multiple cameras, quads and multiplexers help to cut down on the amount of additional equipment needed for a dedicated surveillance system. However, DVR digital video recorders with multiple video inputs are quickly replacing quads and multiplexers. DVRs are now capable of doing what required a processor andVCR in the past (plus a whole lot more).  Click here to see ICR's full line of DVRs.

NTSC is the analog television system in use in Canada, Japan, South Korea, the United States, and some other places, mostly in the America. It is named for the National Television System Committee, the industry-wide standardization body that created it. More Detail

ONVIF is an open industry forum for the development of a global standard for the interface of IP-based physical security products. The forum was established by Axis, Bosch and Sony in October 2008 and now has over 100 members. It is based on standard web-service technologies such as SOAP, WSDL and XML. More Detail.

PAL is another major analog television system in use in large part of the world, mainly Europe, China, and other places. PAL system denotes 625 Lines and 50Hz comparing to NTSC system's 525 Lines and 60Hz. More Detail

The Point-to-Point Protocol over Ethernet (PPPoE) is a network protocol for encapsulating Point-to-Point Protocol (PPP) frames inside Ethernet frames. It is used mainly with DSL services where individual users connect to the DSL modem over Ethernet and in plain Metro Ethernet networks. It was developed by UUNET, Redback Networks and RouterWare and is available as an informational RFC 2516.

PTZ stands for equipment (mostly cameras) with the ability to pan, tilt, and zoom, usually by remote user control. Much of PTZ equipment is completely integrated, meaning there is only one controller necessary to operate all three features. See ICRealtime's PTZ cameras.

Quad Processor is a video switching device that accepts video input from four cameras and converts them to all display on one monitor and / or video recorder. When using multiple cameras, quads and multiplexers help to cut down on the amount of additional equipment needed for a dedicated surveillance system. However, DVR digital video recorders with multiple video inputs are quickly replacing quads and multiplexers. DVRs are now capable of doing what required a processor and VCR in the past (plus a whole lot more).  Click here for info on ICR's quad processor.

RCA (Radio Corporation of America) connector is a common connector plug for standard consumer video and audio equipment. This type of connector plug is also knon as a "phono" plug. RCA jacks are found on all VCRs and televisions equipped to handle a composite video input. In most cases, RCA jacks are color coded yellow, white, and red. BNC plugs are easily adapted to standard consumer RCA connectors using a simple one-piece plug adapter.  More Detail

A colour's saturation is the intensity of the colour in the active picture.  It is based on the colour's purity; a highly saturated hue has a vivid, intense colour, while a less saturated hue appears more muted and grey.   More Detail

Signal to Noise Ratio indicates the ratio of noise to actual total signal (in a video or audio signal). The S/N number measures how much higher the signal level is to the level of background electronic noise, so a higher number means a clearer and crisper picture. Signal-to-noise ratio is expressed in decibels (dB).  More Detail

The Texas Instruments DaVinci Technology combines TI's offering of digital signal processing chips, software, tools and support for developing a broad spectrum of optimized digital video end equipments. The DaVinci DSP is part of the popular TMS320 DSP family.
A typical multimedia system such as a digital video recorder or digital camera can be split roughly into two pieces: control and media. The control portion handles tasks such as memory card or hard disk access, user interface, and networking, while the media portion covers tasks such as encoding and decoding of audio and video. A general-purpose processor performs well in control tasks, but only the fastest of these processors are sufficiently powerful for intensive media-related tasks such as real-time, high-quality video encoding. A DSP, on the other hand, is superb at the repetitive, easily parallelizable media-related tasks, but usually performs poorly in control-related jobs.The idea behind the DaVinci family of processors is that by using both a general-purpose processor and a DSP, the control and media portions can both be executed by processors that excel at their respective tasks. The integration of these two components into one chip simplifies the system design and allows for more efficient communication between the two components.The DaVinci family of processors now scales from multiple core devices (e.g. DM644x) to single core DSP devices (e.g. DM643x) to single core ARM devices (e.g. DM355).More Detail.

A transient voltage suppressor or TVS is a general classification of an array of devices that are designed to react to sudden or momentary overvoltage conditions. One such common device used for this purpose is known as the transient voltage suppression diode that is simply a zener diode designed to protect electronics against overvoltages. Another design alternative applies a family of products that are known as metal-oxide varistor (MOV) that protect electronic circuits and electrical equipment. More Detail.

UPS sometimes called an uninterruptible power source, is a device which maintains a continuous supply of electric power to connected equipment by supplying power from a separate source when utility power is not available.  More Detail

A wide area network or WAN is a computer network covering a wide geographical area, involving a vast array of computers. This is different from local area networks (LANs) that are usually limited to a room, building or campus. The most well-known example of a WAN is the Internet.

WANs are used to connect local area networks (LANs) together, so that users and computers in one location can communicate with users and computers in other locations. More Detail

See also Internet, LAN.

WDR is a feature of some CCTV cameras that can produce a clear image when there are very bright and very dark areas simultaneously in the field of view of the camera.  This feature is particularly useful in camera situations with a lot of backlight, such as when an indoor camera is pointed towards a door or window.  More Detail.