Preliminary Issues

Note that closed captions play a broader role than the subtitles you may have seen in foreign movies or DVDs. That's because most subtitles assume that the viewer can hear, but doesn't understand the language. For this reason, noises such as gunshots, screams, music welling up, dogs barking, and cars beeping may not be noted in the subtitle text.

Closed captions assume that the viewer cannot hear. For that reason, to comply with Section 508, closed captions must "contain speech or other audio information necessary for the comprehension of the content." If you're producing a DVD for government use, you'll need to add all the audio cues necessary to satisfy this requirement.

It's important to note that captioning for broadcast and captioning for streaming video and DVD involve completely different techniques and technologies. Captioning for broadcast involves expensive hardware and software to insert the captioned text directly into the video file.

In contrast, captioning for streaming and DVD involves creating text files in inexpensive (or free) shareware programs and then linking the text file to the video file for streaming, or importing the text file into the DVD authoring program to create subtitles. While some broadcast captioning systems can export text strings for DVD and streaming, if you're not concerned with broadcast, inexpensive programs function just as well.

This chapter focuses entirely on closed captioning for streaming video and DVD and does not address broadcast-specific requirements or technologies. It also focuses solely on the captioning requirements for on-demand files; live event captioning uses a different set of rules and obviously different transcription requirements.