CCTV Abbreviations CCTV Acronym Definition     A/V audio / video AVI Audio Video Interleave - An audio-video standard designed by Microsoft. AES auto electronic shutter - the ability of the camera to compensate for moderate light changes by adjusting the camera shutter without the use of auto iris lenses. AGC automatic gain control - this feature adjusts the brightness level of the video to keep it at a consistent level. BLC back light compensation - a feature on newer CCD cameras which electronically compensates for high background lighting to give detail which would normally be silhouetted. BNC Bayonet Nut Coupling - A commonly used connection for audio/video (A/V) applications. Uses a mount similar to the way a bayonet knife is mounted onto the end of a rifle, BNCs are used to connect a variety of different coaxial cable types. After the plug is inserted, it is turned, causing pins in the socket to be pinched into a locking groove on the plug. CAT5 Category 5 (cable) - the type of cable that is used in networking applications. CCD CCTV security cameras produce images using CMOS or CCD (Charge Couple Device) chips. CCD chips are higher quality and produce a better image than CMOS. CMOS complementary metal oxide semiconductor - Pronounced see-moss, CMOS is a widely used type of semiconductor. CCTV Closed-circuit television DVR digital video recorder - a digital video recorder is basically a computer that converts the incoming (analog) signal from the cameras to digital, and compresses it, and stores it. The DVR replaces the function of a multiplexor (or quad or switcher) and a security VCR. There are many advantages of digital video recorders over their analog counterparts. FPS frames per second - in digital video applications, refers to the number of video images that can be captured, displayed, or recorded in a second. Also referred to as the 'frame rate' or 'refresh rate'. GHZ gigahertz JPEG (or JPG) Pronounced "jay-peg" and stands for "Joint Photographic Experts Group" who designed the standard. This is a standard way of compressing images which works particularily well for photographic images (as opposed to graphic art). MHZ megahertz MPEG (or MPG) Pronounced "em-peg" and stands for "Motion Picture Experts Group" who designed the standard. This is a standard way of compressing audio and video files. (It's also the technology behind the now world-famous MP3 music files.) POE power over ethernet - an adaptor that allows you to transmit power to a security camera through CAT5 (aka ethernet) cable. PTZ pan-tilt-zoom - PTZ cameras allow you to adjust the position ('pan' is side-to-side, 'tilt' is up-and-down) and focus ('zoom') of the camera using a remote controller. Due to this added functionality, these cameras tend to cost much more than non-PTZ cameras RG59 An RG-59 is a common coax cable used in CCTV applications. RCA . S/N ratio signal to noise ratio; this number represents how much signal noise the camera can tolerate and still provide a good picture. The higher the number the better. VCR Videocassette recorder; an electronic device for recording and playing back video images and sound on a videocassette.