International Captioning


History of Line-21 Closed Captioning

In September, 1958, Congress passed a law which, in 1960, led to the creation of Captioned Films for the Deaf, a program for making Hollywood films accessible to the deaf and hard-of-hearing population. These 16 millimeter films were "open captioned" or subtitled; that is, the captions were visible to all viewers without the use of special decoding devices. They were not shown on television; rather, the films were made available by mail order for viewing in private clubs, schools, homes and theaters.

The process by which these captions were created is similar to how foreign- language subtitles were created: the characters themselves were produced by a character-generating device which then "burned" the words directly into the picture via an optical process. In truth, however, they served a much different purpose than subtitles. Subtitles serve the hearing audience by translating the spoken word into a different language, displaying this translation as text on screen. Captions, on the other hand, serve to render the spoken word (and other non- speech audio, such as sound effects) into text on screen in the same language. Captions also indicate not only what is being said, but who is speaking.

In 1962, federal funds were authorized to study, among other things, the viability of and viewer reaction to television captions. Later, in 1971, with funding from the Department of Health, Education and Welfare, the WGBH Educational Foundation in Boston, MA, created The Caption Center with the purpose of making television programs accessible to deaf and hard-of-hearing viewers via open captions. In 1972, Julia Child's The French Chef became the first program to be broadcast with open captions.

In 1973, The Caption Center experimented with news captioning by taping President Nixon's inaugural address, captioning it and then re-broadcasting the address on public television stations. After deeming this experiment a success, The Caption Center received funds from the department of Health, Education and Welfare (HEW) to open caption The ABC Evening News five days per week. The captioned feed of this program occurred approximately five hours after the original network feed only on public television stations. This project continued until 1981. Between 1971 and 1978, funds were also provided for The Caption Center to open-caption selected PBS children's programs, such as Zoom. At about this time, realizing that captioning could potentially have an impact on education, The Caption Center launched a research project into "multi-level" captioning; that is, the use of captions at different reading levels to suit varying audiences.

Despite proof that there was an audience for open captioning, the need for a system which would give deaf and hard-of-hearing people access to programming simultaneously with hearing people was obvious. The search for a "closed- captioning" system began in 1971. That year, two methods of "invisibly" transmitting data were tested: one in the horizontal blanking interval, and one in the VBI. The former method was ruled out because misaligned television sets would, in fact, inadvertently display the data. The VBI method, previously considered by the National Bureau of Standards (NBS) as appropriate to carry time and frequency information, was deemed worthy of further research.

In January, 1972, a subcommittee of the National Association of Broadcasters (NAB) met and decided that closed captioning was technically possible. That same month, PBS was contracted to begin a feasibility study. Not long after, it was discovered that transmitting data in the VBIÑ specifically, on line 1Ñ caused disturbances in the picture; subsequently, the line 1 system was scrapped. In 1972, PBS solved the problem by proposing that line 21 of the VBI be used for caption data transmission. NAB accepted the proposal but specified that, among other things, an effective, low-cost decoding device would have to be developed before any closed-captioning service could be launched.

Between 1973 and 1975, PBS and WGBH conducted intensive studies that proved closed captioning would provide a greatly needed service for the deaf and hard-of- hearing community. Also during that time, PBS demonstrated that a set-top decoder could be developed and sold for approximately $250 (it was estimated that to build the decoding technology into television sets would cost approximately $100). In 1975, results from PBS tests resulted in a petition to the FCC for permanent use of line 21 of the VBI for closed captioning. This petition was approved in 1976. The next year, work began on development of a set-top decoding unit as well as built-in decoder technology.

In the late 1970s, as closed-captioning technology was being readied for air, advocates of closed captioning faced an awkward problem. Networks did not want to pay for captioning because of the potentially small audience for the service, and it made little sense to manufacture and distribute decoders if there were few closed captioned programs available. Additionally, they objected to essentially helping fund PBS, a competitor, by paying for closed captioning. To help resolve this dilemma, the U.S. Government announced it would create a non-profit agency to do the captioning for the networks. To this end, the National Captioning Institute (NCI) was set up in Alexandria, Virginia, with start-up funds provided by HEW. With a commitment from ABC, NBC and PBS (CBS followed in 1982) to closed caption 15 program hours per week, NCI officially opened its doors for business in March of 1980.

Since their introduction in 1980, sales of caption decoders (marketed under the name "TeleCaption adapter") have been slow. Part of the reason is cost: the original TeleCaption I sold for about $250; in 1992, costs for TeleCaption Adapters models 3000, 4000 and VR-100 ranged from $135-$175. However, there are other reasons: not all consumer electronics stores carry decoders, making them hard to find; set-top decoders must be physically attached to a television set or VCR, entailing wiring which may be too complex for many users. Additionally, the largest audience for closed captions is hard-of-hearing people, many of whom are reluctant to admit they have a hearing loss, and thus are reluctant to display a device on their television sets which makes this hearing loss obvious. Many deaf or hard-of-hearing children are born to hearing parents, who are unaware that captions may help their child learn to read more easily. Finally, publicity for decoders has been lacking. A 1992 estimate placed the number of decoders sold to date at approximately 400,000. This does not necessarily mean that only 400,000 people watch captioning, as more than one viewer per decoder may be assumed.

In the late 1980s, a movement was begun to require television manufacturers to build caption decoders into television receivers. The result of these efforts, the Television Decoder Circuitry Act (PL 101-431, which took effect on July 1, 1993), requires closed-caption decoding capability to be a built-in feature of all television sets 13 inches or larger manufactured for sale in the United States. With approximately 20 million TV sets of this size sold in the U.S. each year, nearly every home is expected to have at least one caption-capable set by the end of the century. There are approximately 22 million deaf and hard-of-hearing people in the United States; now, with captions available at the touch of a button, those who need closed captions the most will have easier access to the service than ever before.

The Caption Center was instrumental in drafting and passing the Television Decoder Circuitry Act. As the Electronic Industries Association (EIA) proposed and the FCC approved the new decoder specification, Caption Center staff advocated simple, cost-effective upgrades to the existing closed captioning system. Working with the EIA and the FCC, Caption Center staff joined CPB/WGBH National Center for Accessible Media (NCAM) management to develop captioning standards for NTSC closed captioning, and produced a day-long technical seminar for the entire captioning industry of North America in 1992.

Reaction to this law from the television industry ranged from opposition to full, enthusiastic support. In 1989, when the legislation was first proposed, television manufacturers were unhappy that they might soon be faced with a new government regulation. However, once the law passed, comments from manufacturers became more agreeable. After the FCC issued its Report and Order 91-119 as modified by FCC Memorandum, Opinion and Order FCC 92-157, manufacturers began to support the law enthusiastically. This was due, in part, to the acceptance that decoder circuitry would add little to the cost of television sets. Also, manufacturers saw that line-21 technology could be used for purposes other than closed captioning: for example, Extended Data Service (XDS; see below).

From the outset, every major literacy organization endorsed passage of the Television Decoder Circuitry Act. Now that captions are more easily available than ever before, educators everywhere are finding that captions can have a beneficial effect both in and out of the classroom. For example, research at Temple University showed that seventh- and eighth-grade ESL students using a captioned program did better on written and oral examinations than students who did not use captioned programs. The study also pointed to an improvement in vocabulary and in understanding the concepts conveyed by the words. The CBS network is experimenting with broadcasting its children's programs with open captions. Along with WGBH, CBS produced a teacher's guide to using captioned television programs in elementary classrooms. The guide, called Words to Watch, includes caption-related activities and games. (See Appendix B for a sample guide.) Finally, in Canada, a report was commissioned by Canada Caption (a captioning advocacy group), McLean-Hunter Cable and the Canadian Government to study the use of captions in adult ESL programs. This study found captions extremely helpful to students enrolled in ESL courses, and dramatic improvement in comprehension and usage was experienced by the study group.

In addition to mandating that decoders be built into most television receivers, the decoder act also charged the FCC with setting technical specifications for TV receiver manufacturers. In the process, the FCC added new features to decoders to improve the look and flexibility of closed captioning. Following the FCC's action, the EIA defined still more new features as premium options. These features include the use of color captions, a true italic font, the use of lower-case descenders, an extended character set which supports captions in all Roman- alphabet-based languages, as well as additional band-width for U.S. broadcast in line 21, field 2.


NCAM | | WGBH Educational Foundation |