There Are 3 Types Of Captioning
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It's called "Closed Captioning" because the captions are not shown until special decoder hardware reveals them. This is distinguished from "open captions" where the captions are visible to all viewers all the time.
For the technically oriented, the caption - in the form of an electrical signal - is buried on line 21 of the vertical blanking interval in the analog video signal or tucked in a digital video packet. Government regulations have established the encoding method, available characters and caption layout (32 characters in four of 15 lines).
The viewer has to have a decoder to see the captions. But the decoders are now automatically built into all new televisions sets made in the US. These decoders interpret the information on line 21 and display the captions on the viewer's screen.
Closed captioning is typically displayed as white block letters on a black background.
More about closed captioning...
Subtitles are commonly used on the Internet (also known as "Media Captioning") and for foreign languages on video and DVDs.
Unlike closed captioning you don't need a caption decoder to see subtitles. Compared to closed captioning, subtitling is a lot more flexible too. As a rule, subtitling uses proportionally spaced fonts displayed on a transparent background. However, you can use AutoCaption to subtitle with just about any font style, font colors, graphics, or background.
Traditionally subtitling was permanently etched into the video by hand with a Character Generator -- a very time consuming process. In the 1980's the first versions of AutoCaption changed all that by automating the process using the Chyron® CODI™ character generator. Today it's much more efficient to use AutoCaption3 and a Magni® MCP™ overlay generator to subtitle traditional broadcast video.
With 32 channels of subtitling that can be turned on or off and selected at will, DVDs are quickly replacing traditional subtitling. AutoCaption's subtitling features are designed to be a particularly efficient way to make the subtitling assets required by all DVD formats.
Subtitling Internet material is also a growing market. AutoCaption will make timed text files to use when captioning conventional HTML (SMIL), captioning Google media files (SUM) or captioning proprietary Quick Time (FLV or TT) for Internet as well as for computer CD and DVD applications.
"Supertitling" is when captions are electronically displayed to the entire audience at events like opera and theater. We have a stand-alone system available. (see Digital Tech Services for more)
AutoCaption supports all classes of media captioning:
- Closed Captioning on one or both channels
- Video subtitling using a character or overlay generator
- DVD subtitling on one or more of 32 channels
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