Real-time captioning
Real-time captions are created as an event takes place. A captioner (often trained as a court reporter or stenographer) uses a stenotype machine with a phonetic keyboard and special software. A computer translates the phonetic symbols into English captions almost instantaneously. The slight delay is based on the captioner’s need to hear the word and on the computer processing time. Real-time captioning can be used for programs that have no script; live events, including congressional proceedings; news programs; and nonbroadcast meetings, such as the national meetings of professional associations.
Although most real-time captioning is more than 98 percent accurate, the audience will see occasional errors. The captioner may mishear a word, hear an unfamiliar word, or have an error in the software dictionary. Often, real-time captions are produced at a different location from the programming and are transmitted by phone lines. In addition to live, real-time captioning, captions are being put on prerecorded video, rental movies on tape and DVD, and educational and training tapes using a similar process but enabling error correction.
