The National Captioning Institute was founded in early 1979 to produce captions for commercial and public television programs. NCI uses a system called dosed captioning, whereby the captioned information is transmitted along with the regular picture and sound portion of the television program but is not seen on a normal home television receiver. Only with a special decoder device can the captions be seen. This device is currently marketed by Sears, Roebuck and Co. and is called "TeleCaption." It has been available to the consumer since March 15, 1980. Three networks are participating in this service, PBS, ABC, and NBC. By the end of 1980, it is expected that more than 22 hours per week of captioned programming will be available to viewers.
The closed captioning system, sometimes referred to as Line 21, records captioned electronic codes on Line 21 of the television vertical blanking interval—a portion of the video signal. These codes are read by the decoder which then generates the captions that are displayed on the screen of any normal home television receiver.
The closed-caption system represents the culmination of almost 10 years of technological development and the cooperative efforts of the Federal Government, nonprofit agencies, professional groups, groups representing the deaf and hearing impaired, civic organizations, and commercial industry. It is a service that's designed to meet the communication needs of 14 million hearing-impaired citizens in this country.
For the future, many more populations can be served through closed captions. Bi-lingual, particularly Hispanic Americans, reading disabled children, and hospitalized and institutionalized people who are in environments in which noise must be kept to a minimum can and will be served through closed captioning of television programs.
As we look to the future, we look for additional technological developments that will allow the closed-captioning service to expand beyond the captioning of prerecorded videotape programs. It will include captioning of news and public affairs, sports, real-time captioning—captioning as it is happening and further exploration of the use of captions for bi-lingual groups and direct captioning of film.