VAR: Value Added Reseller. A company which resells hardware and software packages to developers and/or end-users.

VCR: Video Cassette Recorder. An analog magnetic recording and playback machine. Generally used for recording and viewing full-motion video.

VDI: Video Device Interface. A software driver interface that improves video quality by increasing playback frame rates and enhancing motion smoothness and picture sharpness. VDI was developed by Intel and will be broadly licensed to the industry.

VDRV: Variable Data Rate Video. In digital systems, the ability to vary the amount of data processed per frame to match image quality and transmission bandwidth requirements. DVI symmetrical and asymmetrical systems can compress video at variable data rates.

Vector Graphics: Images defined by sets of straight lines, defined by the locations of the end points.

Vertical Interval Switching: Randomly switching from one video signal to another, will often result in a jump in the picture upon playback. The problem is compounded when the tape is copied. To avoid this problem, switching is best performed on synchronized signals during the vertical blanking period, known also as the vertical interval. This allows complete replacement of one whole frame by a second whole frame resulting in a very smooth on-screen switch.

VESA: Video Electronics Standards Association. A 32-bit local bus standard that is compatible with both ISA and EISA cards. Many manufacturers of local bus adapters use this standard because of its speed.

VGA: Video Graphics Array. Standard IBM PC video display. Provides medium resolution text and graphics. VGA pixel resolution is 640X480.

VHS: Video Home System. Consumer videocassette record/playback tape format using half-inch wide magnetic tape. The most common home VCR format in the U.S.

VHS Hi-Fi: An improved stereo audio recording/playback system found on some camcorders and VCRs. Because the audio tracks are mixed and recorded with the video signal, audio-only dubbing of these tracks is not possible.

VHS-C: VHS-Compact. A miniature version of the VHS tape format utilizing smaller cassettes that may also be played on standard VHS machines by using an adapter cartridge.

Video: The picture portion of a program, or, the picture track recorded on a videotape. A videotape typically contains one video (picture) track, up to four audio (sound) tracks, and one timecode track.

Video Bandwidth: The range between the lowest and highest signal frequency of a given video signal. In general, the higher the video bandwidth, the better the quality of the picture. Video bandwidths used in studio work typically vary between 3 and 12 MHz. Consumer VCRs are generally capable of 3-5.5 MHz.

Video Camera: A camera which contains an electronic image sensor rather than photographic film. The lens focuses an image on an electronic tube or CCD chip. A camera has electronic circuitry which generates color and sync pulses. Most portable consumer cameras are equipped with a full complement of audio circuitry, e.g., microphone, audio amplifier and additional audio electronics. In order to obtain better quality images, a professional camera has three tubes or a triple CCD system, one for each basic color. Most professional cameras have a genlock input, which allows the camera to be synchronized to an external source. Some cameras also include basic character generators for titling purposes.

Video Editing: A procedure for combining selected portions of video footage in order to create a new, combined version. A variety of editing consoles are available. During video editing, special effects such as wipes, dissolves, inserts, etc. can be added. Professional editing is done using time code recorded on every frame of the magnetic tape allowing single frame accuracy. Audio editing is often carried out simultaneously with video editing.

Video Enhancer: A general term used to describe a device used to correct video image problems.

Video Gain: The nominal composite video signal level is 1 volt. At this level, a fully saturated image is transmitted and boosting the signal offers no advantage. Most video equipment is designed to output the same 1-volt level video signal. In cases where the signal level has been reduced, such as after a long cable run, an amplifier with video gain may be employed to restore the proper level.

Video Mixer: A device used to combine video signals from two or more sources. Inputs are synchronized, then mixed along with various special effects patterns and shapes. A video mixer usually generates sync signals allowing genlocking of additional video sources to the first source.

Video Printer: A special device used to capture a single frame of video to create a hard copy print.

Video Projector: A display device which projects a video or computer image onto a large screen. The classic video projector has three primary color video tubes which converge on-screen to create the full color image. Single tube projectors eliminate convergence problems but compared to three tube systems, project a relatively lower quality image.

Video Toaster: An extremely successful but low-end desktop video device manufactured by NewTek. Works with Amiga and Macintosh computers. Reduced the price point for video switching and digital effects by a factor of 10. Quality is awful, but the low-end market segment loves it.

Video Wall: A large array of several monitors, placed close to one another in the shape of a video screen or "wall." Each monitor is fed only part of the original video image by using a video-wall generating unit. This device is a digitally-based processor which converts the original analog video signal to digital, rescans, resamples and generates several individual analog video outputs for driving each array monitor separately. When viewed from a distance, the effect can be very dramatic.

VITC: Vertical Interval Time Code. A popular method for recording time code onto videotape. A time code address for each video frame is inserted in the vertical interval (the vertical blanking period) of the video signal, where it is invisible on-screen yet easily retrieved, even when a helical scanning VCR is in pause mode. The most common form of VITC is SMPTE-VITC.

virtual camera: A camera view that is totally synthetic and is executed entirely within the software application.

VTR: Video Tape Recorder. A video recording and playback tape deck, usually of professional quality.