Varifocal Lens : This is a lens with a manually adjusted focal length. The field of view can be adjusted easily after the camera is installed. This simplifies installation with one lens type accommodating multiple locations.
VBI : Vertical Blanking Interval. This refers to the 32 blank lines between fields in the normal NTSC video signal. Many manufacturers embed information in this area of the signal.
VCR : An acronym for Video Cassette Recorder. (Aka: video recorder).
Vertical Market : Vertical markets are customers grouped by their market segment. Examples are casinos, airports, hospitals, retail stores, convenience stores, etc.
VGA : Vector Graphics Array. The standard computer monitor is a VGA.
Video Analytics : This is the generic term used to identify any number of software based video tools used to make determinations based on the changing video content of a camera. A few examples of video analytics are: Auto tracking, motion exception, missing/found object, people count, etc.
Video Clip : This is a (usually) short video saved from a database to document an issue. The video clip can be reviewed in a PC and maintained as a record of the incident. A video clip is often provided to the police to investigate an incident and/or used as evidence in a court case.
Video Loss : This term refers to cameras that were once an active part of the system (connected to a DVR) and the video signal has been lost. This provides an alarm to alert the operator to the video lost situation. This loss could be due to vandalism or to a component failure. Most likely it is due to a bad cable connection.
Video Motion Detection : A method of detecting movement in the view of the camera by the electronic analysis of the change in picture contrast.
VMS (Video Management System) : This is the control software used to manage multiple DVR and NVR systems. The name may change from company to company. CMS (Control Management Software) and Enterprise Software are other common terms used for the software that manages multiple systems.