Editing VHS (section)

== Signal standards ==
VHS can record and play back all varieties of [[Broadcast television systems|analog television signals]] in existence at the time VHS was devised. However, a machine must be designed to record a given standard. Typically, a VHS machine can only handle signals using the same standard as the country it was sold in. This is because some parameters of analog broadcast TV are not applicable to VHS recordings, the number of VHS tape recording format variations is smaller than the number of broadcast TV signal variations—for example, analog TVs and VHS ''machines'' (except multistandard devices) are not interchangeable between the UK and Germany, but VHS ''tapes'' are. The following tape recording formats exist in conventional VHS (listed in the form of standard/lines/frames):

* [[SECAM]]/[[625 lines|625]]/25 (SECAM, French variety)
* [[SECAM#MESECAM (home recording)|MESECAM]]/625/25 (most other SECAM countries, notably the former Soviet Union and Middle East)
* [[NTSC]]/[[525 lines|525]]/30 (Most parts of Americas, Japan, South Korea)
* [[PAL]]/525/30 (i.e., [[PAL-M]], Brazil)
* [[PAL]]/625/25 (most of Western Europe, Australia, New Zealand, many parts of Asia such as China and India, some parts of South America such as Argentina, Uruguay and the Falklands, and Africa)

PAL/625/25 VCRs allow playback of SECAM (and MESECAM) tapes with a [[monochrome]] picture, and vice versa, as the line standard is the same.
Since the 1990s, dual and multi-standard VHS machines, able to handle a variety of VHS-supported video standards, became more common. For example, VHS machines sold in Australia and Europe could typically handle PAL, MESECAM for record and playback, and NTSC for playback only on suitable TVs. Dedicated multi-standard machines can usually handle all standards listed, and some high-end models could convert the content of a tape from one standard to another [[on the fly]] during playback by using a built-in standards converter.

S-VHS is only implemented as such in PAL/625/25 and NTSC/525/30; S-VHS machines sold in SECAM markets record internally in PAL, and convert between PAL and SECAM during recording and playback. S-VHS machines for the Brazilian market record in NTSC and convert between it and PAL-M.

A small number of VHS decks are able to decode [[closed captioning|closed captions]] on video cassettes before sending the full signal to the set with the captions. A smaller number still are able, additionally, to record [[subtitles]] transmitted with world standard [[teletext]] signals (on pre-digital services), simultaneously with the associated program. S-VHS has a sufficient resolution to record teletext signals with relatively few errors,<ref>{{cite web|url=http://www.transdiffusion.org/2016/01/07/teletext-time-travel |title=Teletext time travel |publisher=transdiffusion.org |date=January 7, 2016 |access-date=January 19, 2016}}</ref> although for some years now it has been possible to recover teletext pages and even complete "page carousels" from regular VHS recordings using non-real-time computer processing.<ref>{{Cite web|url=https://teletextarchaeologist.org/faq/|title=FAQ – the Teletext Archaeologist|access-date=2021-07-27|archive-date=2021-07-27|archive-url=https://web.archive.org/web/20210727022421/https://teletextarchaeologist.org/faq/|url-status=dead}}</ref>