HDCVI or High Definition Composite Video Interface, is a new HD-over-Coax technology developed by Dahua, who are a world leading manufacturer of CCTV equipment. It allows for high mega-pixel resolution information to be sent down standard coaxial cabling. Using special technology such as Auto Signal Compensation, it also allows for much longer transmission distances of camera images down the cable compared to other HD-over-coax technologies. HDCVI also allows for audio and control signals to be sent down the same coax cable without the need for additional cables like more traditional analogue based systems. This way, buildings with existing coax cabling do not have to spend thousands having all of its infrastructure replaced for new CAT5 cabling and can upgrade to a HD video system for much less.