Section 504 symbols    


What is Captioning?

Captioning is the transcription and subsequent text display of dialog and other auditory information, such as on- and off-screen sound effects, music, and laughter. Captioning is used in many places including videos and films, live performances and demonstrations, lectures, web sites, and television.

Captioning benefits are not limited to people who are deaf or hard of hearing. In loud, crowded venues as well as hushed, quite settings, captioned video allows sighted visitors to read what they cannot hear. Captions also benefit new readers and people who are learning English as a second language.136

There are two categories of captions:

    CLOSED captions are captions that are hidden in the video signal and are invisible without a special decoder. They are hidden in an area that is called line 21 of the vertical blanking interval (VBI).

    OPEN captions are captions that have been decoded, so they have become an integral part of the television picture, like subtitles in a movie. Open captions cannot be turned off. The term "open captions" is also used to refer to subtitles created with a character generator.137

Caption Styles138

There are three ways that captions can be presented to a viewer:

    Roll-up captions are used almost exclusively for live events. The words appear one at a time at the end of the line, and when a line is filled, it rolls up to make room for a new line. Older decoders can only display roll-up captions at the bottom of the screen. Newer ones can place captions wherever the captioner wants them.

    Pop-on captions are the standard for pre-taped material. The entire caption appears, all at once, anywhere on the screen. When a pop-on caption appears, all captions previously on the screen are erased.

    Paint-on captions are free-form in their positioning, like pop-on captions, but they don't erase what was already on the screen. The name comes from the way they are drawn on the screen a letter at a time, so you can see them "paint on" to the screen. They are not used much yet, except for commercials and special effects.

How are realtime [live] captions generated?139

Realtime [live] captions are performed by stenocaptioners, who are court reporters with special training. They use a special keyboard (called a "steno keyboard" or "shorthand machine") to write what they hear as they hear it. Unlike a traditional "QWERTY" keyboard, a steno keyboard allows more than one key to be pressed at a time. The basic concept behind machine shorthand is phonetic, where combinations of keys represent sounds, but the actual theory used is much more complex than straight phonics.

Stenocaptioners are capable of writing at speeds of up to 250 words per minute, or even faster in short bursts.

The steno keyboard is connected to a computer system where the captioning software formats the stream of steno characters into captions and sends it to a caption encoder. This can be done either directly or through telephone modems.

Methods of captioning140

  • Stenocaptioning

    Live captions are usually displayed in three lines rolling up from the bottom of the screen and are produced by "stenocaptioners" who listen to the show as it airs, typing the words in code on a shorthand keyboard. With live captioning, a few errors are unavoidable.

    Stenocaptioners prepare for live programs ahead of time by updating their "dictionaries" with phonetic symbols or "briefs" for anticipated names and places. The symbols are converted into English words by translation software, formatted into caption data, and sent over telephone lines to be mixed with the video signal. The closed-captioned video signal is then sent to your home via satellite, airwaves, or cable. Your decoder changes the data into captions displayed on your screen. All this happens one to three seconds after a speaker's words are spoken. This allows no time to make any corrections. One wrong keystroke can produce a strange combination of letters or syllables. A poorly prepared dictionary can also produce errors.

    You can recognize stenocaptioning because there are pauses as the words and phrases paint onto the screen. Some news programs are captioned with a combination of stenocaptioning and "prescripted" captions. The prescripted captions paint on smoothly one row at a time. Since these captions were typed ahead of time, there should be no errors. When you see pauses within rows, you know that a stenocaptioner has taken over. Stenocaption errors usually result when the computer combines phonetic information to create a wrong (but similar-sounding) word or phrase; for example: "okay you pant" instead of "occupant."

    Most responsible captioning agencies require a 99% accuracy rate for real-time captioning, but at 250 words per minute, even the best and most experienced stenocaptioner can produce up to two errors every minute. Watch the network evening news for examples of experienced stenocaptioning. If you are watching garbled real-time captions and you are sure that poor reception is not creating the problem, the captioning agency may have put an inexperienced person on the air.

  • Electronic Newsroom Captioning

    Some local newscasts are closed captioned using an electronic newsroom system. Such systems provide automatic captioning based on material typed ahead of time into the teleprompter. Late-breaking news, ad libs, and live segments (field reports or weather forecasts) usually go uncaptioned. These systems occasionally put the wrong captions on a story or roll the captioning too fast.

  • Off-line Captioning

    You should expect virtually error-free captioning when a program is taped and captions can be prepared "off-line." Captions should be thoroughly checked and reviewed before broadcast or duplication. It is the captioning agency's responsibility to review its work and ensure high-quality captioning. It is the responsibility of the producers and networks to monitor the work of their captioning agencies.

Please note that a common symptom of poor reception (or technical problems at the TV station) is pairs of missing letters; for example "Good night" might appear as "Good nht". While this may look like a misspelling, it is probably not a problem of sloppy captioning. Rather, poor reception or a technical glitch at the TV station could be the problem.


What Is Braille?
Braille is a series of raised dots that can be read with the fingers by people who are blind or whose eyesight is not sufficient for reading printed material. Teachers, parents, and others who are not visually impaired ordinarily read braille with their eyes. Braille is not a language. Rather, it is a code by which languages such as English or Spanish may be written and read.

What Does Braille Look Like?
Braille symbols are formed within units of space known as braille cells. A full braille cell consists of six raised dots arranged in two parallel columns each having three dots. The dot positions are identified by numbers from one through six. Sixty-four combinations are possible using one or more of these six dots. A single cell can be used to represent an alphabet letter, number, punctuation mark, or even a whole word.

How Was Braille Invented?
Louis Braille was born in Coupvray, France, on January 4, 1809. He attended the National Institute for Blind Youth in Paris, France, as a student. While attending the Institute, Braille yearned for more books to read. He experimented with ways to make an alphabet that was easy to read with the fingertips. The writing system he invented, at age fifteen, evolved from the tactile "Ecriture Nocturne" (night writing) code invented by Charles Barbier for sending military messages that could be read on the battlefield at night, without light.

How Is Braille Written?
When every letter of every word is expressed in braille, it is referred to as Grade 1 braille. Very few books or other reading material are transcribed in Grade 1 braille. However, many newly blinded adults find this useful for labeling personal or kitchen items.

The system used for reproducing most textbooks and publications is known as Grade 2 braille. In this system cells are used individually or in combination with others to form a variety of contractions or whole words. For example, in Grade 1 braille the phrase you like him requires twelve cell spaces. It would look like this:

braille sample




If written in Grade 2 braille, this same phrase would take only six cell spaces to write. This is because the letters y and l are also used for the whole words you and like respectively. Likewise, the word him is formed by combining the letters h and m. It would look like this:
braille sample




There are 189 different letter contractions and 76 short-form words used in Grade 2 braille. These "short cuts" are used to reduce the volume of paper needed for reproducing books in braille and to make the reading process easier.

Grade 1 (or uncontracted) braille has nothing to do with first grade. Most children learn grade 2 (contracted) braille from kindergarten on. In recent years, some teachers have chosen to begin teaching grade 1 braille first, transitioning to grade 2 braille by the mid-elementary years. There is currently no research that supports the superiority of one approach over the other.

Just as printed matter can be produced with a paper and pencil, typewriter, or printer, braille can also be written in several ways. The braille equivalent of paper and pencil is the slate and stylus. This consists of a slate or template with evenly spaced depressions for the dots of braille cells, and a stylus for creating the individual braille dots. With paper placed in the slate, tactile dots are made by pushing the pointed end of the stylus into the paper over the depressions. The paper bulges on its reverse side forming "dots." Because of their portability, the slate and stylus are especially helpful for taking notes during lectures and for labeling such things as file folders.

Braille is also produced by a machine known as a braillewriter. Unlike a typewriter which has more than fifty keys, the braillewriter has only six keys and a space bar. These keys are numbered to correspond with the six dots of a braille cell. In that most braille symbols contain more than a single dot, all or any of the braillewriter keys can be pushed at the same time.

Technological developments in the computer industry have provided and continue to expand additional avenues of literacy for braille users. Software programs and portable electronic braille notetakers allow users to save and edit their writing, have it displayed back to them either verbally or tactually, and produce a hard copy via a desktop computer-driven braille embosser.

Since its development in France by Louis Braille in the latter part of the nineteenth century, braille has become not only an effective means of communication, but also a proven avenue for achieving and enhancing literacy for people who are blind or have significant vision loss. 142

last reviewed/updated on April 2003 

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