Video monitor

A video monitor also called a broadcast monitor, is a device similar to a television, used to monitor the output of a video-generating device, such as a media playout server, IRD, video camera, VCR, or DVD player. It may or may not have audio monitoring capability. Unlike a television, a video monitor has no tuner and, as such, is unable to independently tune into an over-the-air broadcast. One common use of video monitors is in Television stations and outside broadcast vehicles, where broadcast engineers use them for confidence checking of signals throughout the system. Video monitors are used extensively in the security industry with Closed-circuit television cameras and recording devices.

Another important reason why broadcast monitors must be used for video compliance at television or production facilities is they do not perform any video enhancements and try to produce as accurate an image as possible. For quality control purposes, it is necessary for a broadcast monitor to produce (reasonably) consistent images from facility to facility, to reveal any flaws in the material, and also not to introduce any image artifacts (such as aliasing) that is not in the source material. Broadcast monitors will try to avoid post processing such as up-scaling, line doubling and any image enhancements such as dynamic contrast. However, display technologies with fixed pixel structures (e.g. LCD, plasma) must perform image scaling when displaying SD signals as the signal contains non-square pixels while the display has square pixelscite web|url=http://broadcast-monitors.glennchan.info/scaling-artifacts/scaling-artifacts.htm|title=Scaling artifacts and resolution|last=Chan|first=Glenn|date=2008|work= [http://broadcast-monitors.glennchan.info Broadcast Reference Monitors] |accessdate=2008-10-01] . LCDs and plasmas are also inherently progressive displays and may need to perform deinterlacing on interlaced signals.

Professional video broadcast monitors also display on screen, the current video signal format, they might be receiving i.e.: standard definition formats like 576i, 480i or high definition formats like 720p or 1080p. They also have buttons to toggle common aspect ratios like (4:3 or 16:9), and underscaning or overscaning a picture to see lines in the vertical blanking interval (VBI) of video, and check if subtitles in VBI were inserted properly or not. Modern broadcast grade professional monitors also have safe area grid generators, to help position television graphics, lower thirds, within their respective areas i.e. graphics safe, title safe or action safe.

Features

Professional Video monitors have various features that consumer monitors lack such as:

* Conforms to colorimetry standards such as the SMPTE C, Rec. 709, or EBU primaries.
* SDI inputs / outputs.
* AES/EBU Audio decoding.
* Genlock input.
* GPI interface - For receiving external triggers.
* Modular expansion cards that support SD-SDI or HD-SDI single link or dual-link HD-SDI.
* Safe area cage.
* Rack mountable.

Common display types for video monitors

* Cathode ray tube
* Liquid crystal display
* Plasma display

Common monitoring formats for broadcasters

* Serial Digital Interface (SDI, as SD-SDI or HD-SDI)
* Composite video
* Component video

Common monitoring formats for security

* Composite video
* S-Video

ee also

* Computer monitor
* Composite monitor

References