Through captioning, the audio portion of programming is displayed as text superimposed over the video. Closed captioning information is encoded and transmitted along with the video signal of television broadcasts.
The text is not ordinarily visible. In order to display closed captioning, viewers must use either a set-top decoder or a television receiver with integrated decoder circuitry.
In 1990, Congress passed the Telecommunications Decoder Circuitry Act. The Act requires that television receivers with picture screens 33 centimeters (13 inches) or larger contain built-in decoder circuitry designed to display closed captioned television transmissions.
The Act also requires that the FCC take appropriate actions to ensure that closed captioning services continue to be available to consumers. In 1991, the FCC amended its rules to include standards for the display of closed captioned text on analog television receivers. Today, the development of digital broadcasting requires that the FCC again update its rules to fulfill its obligations under the Act.
In 1997, the FCC adopted rules to phase-in the closed captioning of analog video programming. The rules require an increasing amount of captioned new programming over an eight-year transition period, with 100% of all new nonexempt programming required to be captioned by January 1, 2006.
For more information about closed captioning, choose from the following links:
Realtime Closed Captioning
