Have you ever wondered how closed captions work?  Me too, and apparently so did the group of guys that were sitting next to me at the bar the other night.

For live programs, anything that is spoken throughout the broadcast is transcribed by a person using stenotype or steno mask type of machines, and then the phonetic output is instantly translated into text by a computer and displayed on the screen. This is similar to the stenographer at a court hearing.  Can you imagine how fast these people have to type to get the words up fast enough to even come close to people talking?

For pre-recorded programs the captions are prepared by the broadcaster or closed caption company and are positioned on the screen and timed for the audio, this way they match up as closely as they can get them.

So the next time you are watching your HDTV, you’ll know how they get those little black boxes with words in them to appear on your screen.