Editing On-screen display

{{Short description|Superimposed image}}
{{other uses|OSD (disambiguation){{!}}OSD}}
{{More citations needed|date=January 2021}}

[[Image:OSD.svg|thumb|200px|OSD on a television displaying the current channel and volume]]

An '''on-screen display''' ('''OSD''') is an image superimposed on a screen picture, commonly used by modern [[television set]]s, [[video cassette recorder|VCR]]s, and [[DVD player]]s to display information such as volume, channel, and time.

==History==
In the past, most adjustments on TV sets were performed with analog controls such as [[potentiometer]]s and switches. This was used more recently also in monochrome portable TVs. After [[remote control]]s were invented, digital adjustments became common. They needed an external display, which was [[LED]], [[LCD]], or [[Vacuum fluorescent display|VFD]] based.  Including this display increased manufacturing costs.

When [[electronics]] became more advanced, it became clear that adding some extra devices for an OSD was cheaper than adding a second display device. TV screens had become much bigger and could display much more information than a small second display. OSDs display graphical information superimposed over the picture, which is done by synchronizing the reading from OSD video memory with the TV signal.

Some of the first OSD-equipped televisions were introduced by [[Radio Corporation of America|RCA]] in the late 1970s, simply displaying the channel number and the time of day at the bottom of the screen. An OSD chip was added to the General instruments (GI) varactor tuning chip set designed in conjunction with RCA and Telefunken. The original OSD was merely to placate users who were faced with a snowy screen during auto tuning. Something the original architecture had not seen as an issue until it was first demonstrated. Once a display had been injected, at least in 1981, a [[real-time clock]] (RTC) was added to display time and date on video terminals<ref>{{cite book|url=https://books.google.com/books?id=BmUnAQAAMAAJ&q=real+time+clock+to+display+time+and+date+on+OSD|title=Control Engineering|publisher=Technical Publishing Company|year=1981}}</ref> (with greater performance in 1996).<ref>{{cite book|url=https://books.google.com/books?id=eDtWAAAAMAAJ&q=real+time+clock+to+display+time+and+date+on+OSD|title=Electronics World Incorporating Wireless World|publisher=Reed Business Pub.|year=1996}}</ref>

In the 1980s, OSD-capable TVs started to be more common, such as [[Zenith Electronics Corporation|Zenith]]'s "System 3" series. [[Akai]] have been credited with the introduction of OSD in VCRs in the 1980s, including the introduction of on screen programming.<ref>{{cite news|url=https://news.google.com/newspapers?nid=1301&dat=19830424&id=DI1WAAAAIBAJ&pg=6566,8245689|title=Stylish Akai VS-2 appeal|date=Apr 24, 1983|newspaper=The Sydney Morning Herald}}</ref><ref name="Inc.1970">{{cite book|url=https://books.google.com/books?id=hmg9AQAAIAAJ&q=AKAI+first+on+screen+display|title=Billboard|date=26 September 1970|publisher=Nielsen Business Media, Inc.|pages=42–|issn=0006-2510}}</ref> By the mid-1990s, VCRs with these displays became widely available. This made it possible to reduce the size (and cost) of the [[Vacuum fluorescent display|VFD]] or [[LCD]] in the VCR. Eventually, as VCRs declined in popularity and prices fell, many manufacturers dropped the internal display completely, relying completely on the on-screen display. All DVD players also use on-screen displays. Many [[PAL]] television sets use the internal [[Teletext]] decoder's graphics rendering system to further reduce costs.

More recently (as of about 2005), the decline in [[Cathode-ray tube|CRT]]-based TV sets and rise in [[LCD television|LCD]]/[[plasma display|plasma]] televisions has seen the use and availability of dedicated OSD devices decline, as it is more cost effective to integrate OSD functions inside the main graphics processor. Modern LCD television monitors usually incorporate only two or three integrated circuits. Examples of integrated circuits to perform dedicated OSD are [http://www.maxim-ic.com/MAX7456 MAX7456] and STV5730. Both operate with NTSC or PAL, mixing with an existing signal or self-generating. Both have slightly different capabilities. This can be done by [http://www.micro-examples.com/public/microex-navig/doc/081-pic-osd-superimposer.html PIC] video superimposer too.{{citation needed|date=January 2020}}

== First VCR with on-screen display ==
[[Akai]] produced consumer [[video cassette recorder]]s (VCR) during the 1980s. The Akai VS-2 was the first VCR with an on-screen display, originally named the Interactive Monitor System. By displaying the information directly on the television screen, this innovation eliminated the need for the user to be physically near the VCR to program recording, read the tape counter, or perform other common features. Within a few years, all competing manufacturers had adopted on-screen display technology in their own products.

==Computers==
[[File:NotifyOSDSampleLightAndMessage.jpg|thumb|NotifyOSD in Ubuntu]]
Some [[computer software]] also uses OSDs, especially support programs for so-called "enhanced [[computer keyboard|keyboard]]s", which often had additional medias like skipping through music tracks and volume adjustment. Their use outside this field is still uncommon. On-screen displays are also used in [[camcorder]]s, and can display various information both on the viewfinder and on the TV set the camcorder is connected to.

The complexity of graphics offered by such displays has greatly increased over the years, from simple [[monochrome]] images to intricate [[graphical user interface]]s.

Many [[computer monitor]]s have an OSD menu for configuration.

==Known problems==
Several problems exist with regard to on-screen displays. One of them is diagnostics if a television's display system is damaged. Without any external screens, it is almost impossible (without opening the TV) to determine the source of the error. TV accessories that depend heavily on OSDs, such as VCRs or DVD players, are also difficult to configure without the use of a TV. On older VCRs, it was possible to program recording timers without turning on the TV; a modern VCR requires the user to turn on the TV to do so. Usability is generally also decreased with OSDs, as it is necessary to control a multitude of parameters with a few buttons, where earlier, real analog controls with mechanical feedback were available.

The drawbacks of using OSDs do not outweigh their main advantage of being more cost-efficient and allowing to design less separate physical tuning controls, which has led to their widespread use.

== See also ==
* [[Digital on-screen graphic]]
* [[HUD (computing)|Head-up display, in computing]] and [[HUD (video gaming)|in video gaming]]
* [[Television news screen layout]]
*[[Character generator]]
*[[Chyron Corporation]]
*[[Pong]]

== References ==
{{reflist|30em}}

{{DEFAULTSORT:On-Screen Display}}
[[Category:Film and video technology]]