Editing Closed captioning (section)

=== Caption formatting ===
[[TVNZ]] Access Services and Red Bee Media for [[BBC]] and Australia example:
<pre style="color:#004000;">
I got the machine ready.</pre>
<pre style="color:red;">ENGINE STARTING
(speeding away)
</pre>
UK IMS for [[ITV (TV network)|ITV]] and Sky example:
<pre style="color:red;">
(man) I got the machine ready. (engine starting)
</pre>
US WGBH Access Services example:
<pre>
MAN: I got the machine ready. (engine starting)
</pre>
US [[National Captioning Institute]] example:
<pre>
Man: I GOT THE MACHINE READY. 
[ENGINE STARTING]
</pre>
US [[CaptionMax]] example:
<pre>
- I got the machine ready.
[engine starting]
</pre>
US in-house real-time roll-up example:
<pre>
>> Man: I GOT THE MACHINE READY.
[engine starting]
</pre>
Non-US in-house real-time roll-up example:
<pre style="color:#808000;">
MAN: I got the machine ready.
(ENGINE STARTING)
</pre>
US [[VITAC]] example:
<pre>
Man:
I got the machine ready.
[ Engine starting ]
</pre>

==== Syntax ====
For real-time captioning done outside of captioning facilities, the following syntax is used:
* '>>' (two prefixed [[greater-than sign]]s) indicates a change in single speaker.
** Sometimes appended with the speaker's name in alternate case, followed by a [[colon (punctuation)|colon]].
* '>>>' (three prefixed greater-than signs) indicates a change in news story.

Styles of syntax that are used by various captioning producers:
* Capitals indicate main on-screen dialogue and the name of the speaker.
** Legacy [[EIA-608]] home caption decoder fonts had no [[descender]]s on lowercase letters.
** Outside North America, capitals with background coloration indicate a song title or sound effect description.
** Outside North America, capitals with black or no background coloration indicates when a word is stressed or emphasized.
* Descenders indicate background sound description and [[Offscreen|off-screen]] dialogue.
** Most modern caption producers, such as [[WGBH-TV]], use [[mixed case]] for both on-screen and [[Offscreen|off-screen]] dialogue.
* '-' (a prefixed dash) indicates a change in single speaker (used by [[National Captioning Institute]] or [[CaptionMax]]).
* Words in [[italic type|italics]] indicate when a word is stressed or emphasized and when real world names are quoted.
** Italics and [[bold type]] are only supported by [[EIA-608]].
** Some North American providers use this for [[Narration|narrated]] dialogue.
** Some providers use this for [[offscreen|off-screen]] dialogue.
** Italics are also applied when a word is spoken in a foreign language.
* Text coloration indicates captioning credits and sponsorship.
** Used by [[music video]]s in the past, but generally has declined due to system incompatibilities.
** In Ceefax/Teletext countries, it indicates a change in single speaker in place of '>>'.
** Some Teletext countries use coloration to indicate when a word is stressed or emphasized.
** Coloration is limited to white, green, blue, cyan, red, yellow and magenta.
** UK order of use for text is [[white]], [[green]], [[cyan]], [[yellow]]; and backgrounds is [[black]], [[red]], [[blue]], [[magenta]], [[white]].
** US order of use for text is [[white]], [[yellow]], [[cyan]], [[green]]; and backgrounds is [[black]], [[blue]], [[red]], [[magenta]], white.
* [[Square brackets]] or [[parentheses]] indicate a song title or sound effect description.
* [[Parentheses]] indicate speaker's vocal pitch e.g., (man), (woman), (boy) or (girl).
** Outside North America, [[parentheses]] indicate a silent on-screen action.
* A pair of [[eighth note]]s is used to bracket a line of [[lyrics]] to indicate singing.
** A pair of eighth notes on a line of no text are used during a section of instrumental music or even voice tones playing with the music.
** Outside North America, a single [[number sign]] is used on a line of [[lyrics]] to indicate singing or may just instead use the eighth notes without the lyrics playing.
** An additional musical notation character is appended to the end of the last line of lyrics to indicate the song's end.
** As the symbol is unsupported by [[Ceefax]]/[[Teletext]], a [[number sign]] - which resembles a musical [[sharp (music)|sharp]] - is substituted.

==== Technical aspects ====
There were many shortcomings in the original Line 21 specification from a [[typography|typographic]] standpoint, since, for example, it lacked many of the characters required for captioning in languages other than English. Since that time, the core Line 21 character set has been expanded to include quite a few more characters, handling most requirements for languages common in North and South America such as [[French language|French]], [[spanish language|Spanish]], and [[portuguese language|Portuguese]], though those extended characters are not required in all decoders and are thus unreliable in everyday use. The problem has been almost eliminated with a market specific full set of Western European characters and a private adopted [[Norpak]] extension for [[South Korea]]n and [[Japan]]ese markets. The full [[EIA-708]] standard for digital television has worldwide character set support, but there has been little use of it due to [[EBU]] Teletext dominating [[Digital Video Broadcasting|DVB]] countries, which has its own extended character sets.

Captions are often edited to make them easier to read and to reduce the amount of text displayed onscreen. This editing can be very minor, with only a few occasional unimportant missed lines, to severe, where virtually every line spoken by the actors is condensed. The measure used to guide this editing is words per minute, commonly varying from 180 to 300, depending on the type of program. Offensive words are also captioned, but if the program is censored for TV broadcast, the broadcaster might not have arranged for the captioning to be edited or censored also. The "TV Guardian", a television [[set-top box]], is available to parents who wish to censor offensive language of programs—the video signal is fed into the box and if it detects an offensive word in the captioning, the audio signal is bleeped or muted for that period of time.