Cable Modem : This is a modem that allows you to connect to the Internet through your TV cable company. Speeds are similar to DSL.
Call Monitor : This is a secondary monitor connected to a DVR, Multiplexer, etc. This is also called a Spot Monitor. The video displayed is typically a single image. Some units provide multiple outputs.
Cameo : Refers to an individual video image in a multi-screen display.
Camera : This is the basic video collection device that has many forms and configurations. Some are: box cameras (require a separate lens) bullet cameras (slim line all in one construction) dome camera (all in one in a dome design) PTZ camera (mounted on a PTZ platform device) PTZ dome (all in one package). An IP camera can be any of these and connect directly to a network.
C-Mount /CS-Mount Lenses : C-Mount cameras and lenses were the first used in CCTV applications. The lens screws directly into the camera providing a distance of 17.5mm between the back of the lens and the imager. Current CS lenses are smaller and better suited for smaller cameras. The lens to imager distance is 12.5mm. A 5mm spacer called a C-ring, or C-mount is used with CS lenses to bring the lens to imager distance to 17.5mm.
CAT-5 Cable : This refers to category-five cable. This is the typical cable wiring used in Ethernet networks. The cable contains four sets of twisted pair wires. The end connectors are RJ-45 connectors.
CCD : Charge Coupled Device: It is light sensitive and forms the imaging device of most modern cameras. Size is measured diagonally and can be ¼” 1/3,” or ½."
CCIR : Commite Consultatif International Radiotelegraphique. This is a standards committee of the International Telecommunications Union, who made the technical recommendation for the European 625 line standard for video signals (black and white).
CCTV : An acronym for Closed Circuit Television. Originally this was described as a system with cables directly from cameras to viewing devices with no outside world connections. The Internet has changed all that. Now you can access any DVR with browser software through the Internet.
Central Station Monitoring : Monitoring a large number of remote DVRs from a central location using remote software.
Chrominance : This is the color portion of a composite video signal.
CIF : An acronym for Common Intermediate Format. This is a format for digitized video. CIF typically indicates a pixel format of 320x240.
Client Server Network : This is a network where a server (an unattended PC) stores information and shares it with the clients (the attended workstations). The clients depend on the servers for normal operation. The workstations do not necessarily talk to each other.
Client : In CCTV DVR context the Client is the PC running the remote software that accesses the DVR or other device. The device originating the video is the Server.
CMOS : Acronym for Complementary Metal Oxide Semiconductor. This type of IC (Integrated Circuit) technology is used in a wide range of analog circuits. CMOS is used for camera imaging. CMOS cameras were originally low in quality but improvements have been made to the point where they can compete with CCDs quality wise in many applications.
CMS Software : This is an acronym for Central Management Software. This is a generic term used to indicate the installable remote software packages provided by any DVR manufacturer. Each manufacturer has a specific name for their CMS product.
CODEC : This stands for Compressor/de-compressor. Some people call it encoder/decoder. This refers to the software that compresses and decompresses video.
Coexistence : Coexistent systems allow operation of analog and digital video systems using the same PC as the portal to all video management. The term was coined by Infinova. They won an accolades award at ASIS 2010 for using V2216 software to control both analog switches and IP cameras.
Competitive Test : This refers to testing of a competitor’s similar product entry. This is best performed as a side by side test.
Composite Video : The complete visual wave form of the color video signal composed of chrominance and luminance picture information; blanking pedestal; field, line, and color sync pulses; and field equalizing pulses. More simply for CCTV purposes it contains the video signal and horizontal and vertical sync pulses on a single wire.
Compression : Video must be compressed in size in order to make it manageable in the record and remote transmit functions. Typical compression standards include M-JPEG, MPEG-4 and H.264. Some DVR manufacturers use proprietary compression methods that are usually modified versions of the standards.
Convergent Systems : This combines analog and IP solutions by using video encoders to convert analog cameras into an IP stream for control with an NVR (the convergence of analog and IP).
Covert Camera : A covert camera is not visible to the operator of the system. It is intentionally obscured from view and often used for surveillance of employees. An authorized operator with the proper password privileges can view the camera and recorded information.
CRI (Color Rendition Index) : This is a measurement of how accurately a camera captures the reflected color in an image (a scale of 1 – 100). High CRI numbers provide the best results. Faithful color rendition in lighting is said to improve the morale of those working in the environment. CRT: Cathode Ray Tube. This is the picture tube of a normal monitor or television.
CSI : An acronym for Construction Standards Institute. CSI standards cover the entire construction process of buildings including all the systems installed in the building. CCTV/security is only one system of many included in the specs. Some CCTV manufacturers are writing their A&E specs to follow the CSI format.
CVBS : An acronym for Composite Video Baseband Signal. This is the portion of the NTSC broadcast video signal that is used in traditional CCTV. It is the basic video composite signal (video, horizontal and vertical sync signals) minus the carrier frequencies, audio, closed caption and many embedded signals used on broadcast video. Interestingly, the same acronym is also used for Composite Video Broadcast Signal.