Closed captioning
Closed captioning is the process of displaying text on a television, video screen, or other visual display to provide additional or interpretive information, where the viewer is given the choice of whether the text is displayed. Closed captions are typically used as a transcription of the audio portion of a program as it occurs, sometimes including descriptions of non-speech elements. Other uses have included providing a textual alternative language translation of a presentation's primary audio language that is usually burned in to the video and unselectable.
HTML5 defines subtitles as a "transcription or translation of the dialogue when sound is available but not understood" by the viewer and captions as a "transcription or translation of the dialogue, sound effects, relevant musical cues, and other relevant audio information when sound is unavailable or not clearly audible".
Terminology
The term closed indicates that the captions are not visible until activated by the viewer, usually via the remote control or menu option. On the other hand, the terms open, burned-in, baked on, hard-coded, or simply hard indicate that the captions are visible to all viewers as they are embedded in the video.In the United States and Canada, the terms subtitles and captions have different meanings. Subtitles assume the viewer can hear but cannot understand the language or accent, or the speech is not entirely clear, so they transcribe only dialogue and some on-screen text. Captions aim to describe to the deaf and hard of hearing all significant audio content—spoken dialogue and non-speech information such as the identity of speakers and, occasionally, their manner of speaking—along with any significant music or sound effects using words or symbols. Also, the term closed caption has come to be used to also refer to the North American EIA-608 encoding that is used with NTSC-compatible video.
The United Kingdom, Ireland, and a number of other countries do not distinguish between subtitles and captions and use subtitles as the general term. The equivalent of captioning is usually referred to as subtitles for the hard of hearing. Their presence is referenced on screen by notation which says "Subtitles", or previously "Subtitles 888" or just "888", which is why the term subtitle is also used to refer to the Ceefax-based videotext encoding that is used with PAL-compatible video. The term subtitle has been replaced with caption in a number of markets—such as Australia and New Zealand—that purchase large amounts of imported US material, with much of that video having had the US CC logo already superimposed over the start of it. In New Zealand, broadcasters superimpose an ear logo with a line through it that represents subtitles for the hard of hearing, even though they are currently referred to as captions. In the UK, modern digital television services have subtitles for the majority of programs, so it is no longer necessary to highlight which have subtitling/captioning and which do not.
Remote control handsets for TVs, DVD players, and similar devices in most European markets often use "SUB" or "SUBTITLE" on the button used to control the display of subtitles and captions.
History
Open captioning
Regular open-captioned broadcasts began on PBS's The French Chef in 1972. WGBH began open captioning of the programs Zoom, ABC World News Tonight, and Once Upon a Classic shortly thereafter.Technical development of closed captioning
Closed captioning was first demonstrated in the United States at the First National Conference on Television for the Hearing Impaired at the University of Tennessee in Knoxville, Tennessee, in December 1971. A second demonstration of closed captioning was held at Gallaudet College on February 15, 1972, where ABC and the National Bureau of Standards demonstrated closed captions embedded within a normal broadcast of The Mod Squad.At the same time in the UK the BBC was demonstrating its Ceefax text based broadcast service which they were already using as a foundation to the development of a closed caption production system. They were working with professor Alan Newell from the University of Southampton who had been developing prototypes in the late 1960s which became part of the core specification of the Teletext platform.
The closed captioning system was successfully encoded and broadcast in 1973 with the cooperation of PBS station WETA. As a result of these tests, the FCC in 1976 set aside Line 21 for the transmission of closed captions. PBS engineers then developed the caption editing consoles that would be used to caption prerecorded programs.
The BBC in the UK was the first broadcaster to include closed captions in 1979 based on the Teletext framework for pre-recorded programming.
Real-time captioning
Real-time captioning, a process for captioning live broadcasts, was developed by the National Captioning Institute in 1982. As developed in 1992, real-time captioning used stenotype operators who are able to type at speeds of up to 375 words per minute provide captions for live television programs, allowing the viewer to see the captions within two to three seconds of the words being spoken.Improvements in speech recognition technology mean that live captioning may be fully or partially automated. BBC Sport broadcasts use a "respeaker": a trained human who repeats the running commentary for input to the automated text generation system. This is generally reliable, though errors are not unknown.
In the 1980s, DARPA sponsored a number of projects aimed at developing automatic speech recognition software. Much of this work was done by researchers at Carnegie Mellon University. In the 1990s, this program included a novel focus of using this technology for news transcription purposes. Later developments have yielded live, real-time AI-based captioning generating systems.
Full-scale closed captioning
The National Captioning Institute was created in 1979 in order to get the cooperation of the commercial television networks.The first use of regularly scheduled closed captioning on American television occurred on March 16, 1980. PBS developed the line-21 decoder, a decoding unit that could be connected to a standard television set. This was sold commercially by Sears under the name Telecaption. The first programs seen with captioning were a Disney's Wonderful World presentation of the film Son of Flubber on NBC, an ABC Sunday Night Movie airing of Semi-Tough, and Masterpiece Theatre on PBS.
Since 2010 the BBC has provided captioning for all programming across all seven of its main broadcast channels BBC One, BBC Two, BBC Three, BBC Four, CBBC, CBeebies and BBC News.
BBC iPlayer was launched in 2008 as the first captioned video-on-demand service from a major broadcaster with levels of captioning comparable to those provided on its broadcast channels.
Legislative development in the U.S.
Until the passage of the Television Decoder Circuitry Act of 1990, television captioning was performed by a set-top box manufactured by Sanyo Electric and marketed by the National Captioning Institute. Through discussions with the manufacturer it was established that the appropriate circuitry integrated into the television set would be less expensive than the stand-alone box, and Ronald May, then a Sanyo employee, provided the expert witness testimony on behalf of Sanyo and Gallaudet University in support of the passage of the bill. On January 23, 1991, the Television Decoder Circuitry Act of 1990 was passed by Congress. This Act gave the Federal Communications Commission power to enact rules on the implementation of closed captioning. This Act required all analog television receivers with screens of at least 13 inches or greater, either sold or manufactured, to have the ability to display closed captioning by July 1, 1993.Also, in 1990, the Americans with Disabilities Act was passed to ensure equal opportunity for persons with disabilities. The ADA prohibits discrimination against persons with disabilities in public accommodations or commercial facilities. Title III of the ADA requires that public facilities—such as hospitals, bars, shopping centers and museums —provide access to verbal information on televisions, films and slide shows.
The Federal Communications Commission requires all providers of programs to caption material which has audio in English or Spanish, with certain exceptions specified in Section 79.1 of the commission's rules. These exceptions apply to new networks; programs in languages other than English or Spanish; networks having to spend over 2% of income on captioning; networks having less than US$3,000,000 in revenue; and certain local programs; among other exceptions. Those who are not covered by the exceptions may apply for a hardship waiver.
The Telecommunications Act of 1996 expanded on the Decoder Circuitry Act to place the same requirements on digital television receivers by July 1, 2002. All TV programming distributors in the U.S. are required to provide closed captions for Spanish-language video programming as of January 1, 2010.
A bill, H.R. 3101, the Twenty-First Century Communications and Video Accessibility Act of 2010, was passed by the United States House of Representatives in July 2010. A similar bill, S. 3304, with the same name, was passed by the United States Senate on August 5, 2010 and by the House of Representatives on September 28, 2010, and was signed by President Barack Obama on October 8, 2010. The Act requires, in part, any ATSC-decoding set-top box remote to have a button to turn the closed captioning in the output signal on or off. It also requires broadcasters to provide captioning for television programs redistributed on the Internet.
On February 20, 2014, the FCC unanimously approved the implementation of quality standards for closed captioning, addressing accuracy, timing, completeness, and placement. This is the first time the FCC has addressed quality issues in captions.
In 2015, a law was passed in Hawaii requiring two screenings a week of each movie with captions on the screen. In 2022 a law took effect in New York City requiring movie theaters to offer captions on the screen for up to four showtimes per movie each week, including weekends and Friday nights.
Some state and local governments require closed captioning to be activated on TVs in public places at all times, even if no one has requested it.