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Types of captioning 1. Closed captioning The term "closed" in closed captioning indicates that not all viewers see the captions. These are captions that are hidden in the video signal and that are invisible without a special decoder. Technically the caption, which is in form of an electrical signal, is buried on line 21 of the VBI (Vertical Blanking Interval) in the analog video signal or tucked in a digital video packet. The VBI consists of a number of "lines" of video. The 21st line has been allocated to closed-caption information. The viewer therefore has to have a decoder that interprets the information on line 21 and displays the captions on the viewer's screen. Once decoded, the captions display as white block letters on a black background. Closed Captioning encoding methods have been established by Government regulation and allow for two characters of information to be placed in each video frame. There are 30 frames in a second and this translates to 60 characters per second, or about 600 words per minute. Note that it takes one frame to transmit a command - like "go to a new line of roll-up," – but it takes more than one frame to position information on caption. Some features of closed captions are; They can be turned on and off They are Mono-spaced Drawn by the viewer’s TV decoder as characters on the screen They are displayed on a Black background There are 15 lines in the image area and 32 characters per line There are a variety of languages or channels from which a viewer can choose. One may have French and Spanish captions on different channels and they are easy to read more reason why they are very popular. 2. Subtitling Subtitles are textual versions of the dialog in television program. These are commonly displayed at the bottom of the screen and appear either in form of a written depiction of the dialog in the same language or written translation of a dialog in a foreign language. Subtitles are hidden unless requested by the viewer from a menu. They are intended for hearing audiences but always carry additional sound representations for deaf and hard of hearing viewers. They are widely used on the Internet and for foreign languages on video. Unlike closed captioning a viewer doesn’t need a caption decoder to view subtitles. Subtitling is a lot more flexible too and uses proportionally spaced fonts displayed on a transparent background allowing for the use of AutoCaption, which replaced the traditional permanent etching of subtitles into a video, to subtitle with any font style, graphics, background or colors. Some features of closed captions are; The subtitle encoder draws characters Their Background is optional They is a variable number of characters per line They allow for any character or graphic to be used There are about 12 lines that fit in the image area Only 12 lines of subtitled text fit in the space occupied by 15 lines of closed caption text and for this reason subtitling characters need to be a bit larger than closed caption characters. 3. Supertitling Supertitling refers to the electronic display of captions to the entire audience at theatric events, hearings, assembly, lectures or even town meetings. These appear in form of a dialogue that can be read by the audience hence allowing them to read what is being said while watching the performance. Technically, electronic supertitles are electronic signboards made of thousands of LEDs (Light Emitting Diodes) that have largely replaced Surtitles that use video projectors or slides and slide projectors. There are also supertitles that use video or computer monitor displays. Types of closed captioning Definition Closed captions are captions hidden in the video signal that are invisible without a special decoder. There are – types of closed captions. The term "closed" in closed captioning indicates that not all viewers see the captions – and this is what distinguishes then from open captions, which are visible to all viewers. The terms captions and subtitles have different meaning though most of the world takes them to mean the same thing. Subtitles assume the viewer can hear but cannot understand the language, so they translate dialogue and some on-screen text. Captions explain all significant audio content; spoken dialogue and non- speech information such as the identity of speakers and their manner of speaking along with music or sound effects using words or symbols. Application Closed captions are used as a tool by those learning to speak a non-native language, read, or in noisy environments where audio is difficult to hear or intentionally muted. Closed captions are also used by deaf or hard of hearing individuals to assist comprehension and also by viewers who simply wish to read a transcript along with the program audio. Television and video In the production of live programs closed captions are created by a captioner listening to the video conference and key-stroking every word using a special stenographic or stenomask type of machine attached to a computer. The stenomask’s phonetic output is instantly translated into text by the computer and displayed on a screen. This happens after the conferencing system has added the captions to the video signal, and the captions and video may then be sent simultaneously to all participants in the conference. In some cases the transcript is available beforehand and captions are simply displayed during the program after being edited. For programs that have a mix of pre-prepared and live content, such as news bulletins, a combination of the above techniques is used. For prerecorded programs and home videos, audio is transcribed and captions are prepared, positioned, and timed in advance. In PAL and SECAM countries, captioning is broadcasted and stored differently. Although the method of preparation is similar, teletext is used rather than Line 21. A variation of Line 21 is used in PAL countries for videotapes since teletext captions cannot be stored on a standard VHS tape - due to limited bandwidth, although they are available on S-VHS tapes and DVDs. In NTSC programming, captions are encoded into Line 21 of the VBI (Vertical Blanking Interval), a part of the TV picture that sits just above the visible portion and is usually unseen. For ATSC (digital television) programming, three streams are encoded in the video; two of which are backward compatible Line 21 captions, and one a set of up to 63 additional caption streams encoded in EIA-708 format. In the US, for older televisions, a decoder set is usually required. Most television receivers have to include closed captioning and this has been so since the passage of the Television Decoder Circuitry Act. High-definition display screens may lack captioning but HDTV (High-definition TV) sets, receivers, and tuner cards are covered. There are three ways that captions can be presented to a viewer. These are the three style of Line 21 captioning: Roll-up: These are used almost exclusively for live events. They are also called scroll-up or scrolling. The words appear one at a time at the end of the line, from left to right 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 but they can be placed anywhere to avoid covering graphics. Pop-on: These are also called pop-up or block captions and are the standard for pre-taped material. The entire caption appears, all at once, anywhere on the screen. The method is used for most pre-taped television and film programming. When a pop-on caption appears, all captions previously on the screen are erased. Paint-on: 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 free-form in their positioning, but they don't erase what was already on the screen. They are commonly used for commercials and special effects. A program may be packaged to include scroll-up and pop-on captions with scroll- up for narration and pop-on for song lyrics). A musical note symbol (hash sign in UK, Ireland and Australia) is used to indicate song lyrics or background music. Generally, lyrics are preceded and followed by music notes (or hash signs), while song titles are bracketed like a sound effect. Standards vary from country to country and company to company. Capital letter are often used in captioning since many older home caption decoder fonts had no descenders intended for the lowercase letters g, j, p, q, and y, while virtually all modern TVs have caption character sets with descenders. Text can be italicized, with a few other style choices and captions can be presented in special colors as well. There were a lot of limitations in the original Line 21 specification from a typographic perspective, since, for example, it lacked loads of characters necessary for captioning in languages other than English. Captions are often edited to make them easier to read and to decrease the amount of text presented onscreen. Offensive terms are also captioned, but if the program is censored for TV broadcast, the broadcaster might not have arranged for the captioning to be edited or censored also. There is a decoder available to parents who wish to censor offensive language of programs. The video signal is fed into the decoder and if it detects an offensive term in the captioning, the audio signal is muted for that duration of play. DVDs There are NTSC DVDs that carry closed captions in the Line 21 format. This type of captioning is normally carried in a subtitle path labeled either English for the hearing impaired or SDH (Subtitled for the Deaf and Hard of hearing). On some DVDs, the Line 21 captions may perhaps have the same text as the subtitles; on others, only the Line 21 captions incorporate the additional non-speech information considered necessary for deaf and hard of hearing audience. Many deaf and hard of hearing subtitle files on DVDs are variations of the original teletext subtitle files. Blu-ray disc media and HD DVD cannot carry Line 21 closed captioning owing to the design of High-Definition Multimedia Interface (HDMI) specifications that were designed to replace older analog and digital standards, such as VGA, S-Video, and DVI. Movies There are quite a few technologies used to provide captioning for movies in theaters and they fall into two broad categories: open and closed. Open captioning in a theater can be achieved through burned-in captions, projected bitmaps, or in rare cases a display positioned above or below the movie screen. Almost certainly the best known closed captioning choice for theaters is the Rear Window Captioning System from the National Center for Accessible Media. The model allows for a reflection of the captions to display on panel mounted in front of the viewers. The reflective system has also been adopted by other companies like the Cinematic Captioning Systems. Another company, DTS or Digital Theater Systems, who created surround sound have a digital captioning device called the DTS-CSS or Cinema Subtitling System that is a combination of a laser projector which places the captioning anywhere on the screen, and the CD on the thin playback device holds many languages. Video games It had become common for video games to be closed captioned. Many games nowadays at least offer subtitles for spoken dialog during cut scenes, and many contain significant in-game dialog and sound effects in the captions as well. In most games, not only are subtitles available during cut scenes, but any dialog spoken during real-time gameplay will be captioned as well, allowing hard of hearing players to know what enemy guards are saying and when the major character has been identified. The game systems themselves have no role in the captioning as each game must have its subtitle display programmed independently. Video games do not offer Line 21 captioning, decoded and displayed by the television itself but have a built-in subtitle display, more akin to that of the DVDs. Theater Opera houses have used captioning for their productions for a long time while live theater captioning has only lately begun emerging. Display techniques vary, with subtitles, surtitles and the individual displays at use. Telephones Closed Captioned telephony is a new concept in application. This is meant for the deaf people and the hard of hearing. Media monitoring services The capturing and indexing closed captioning text from news and public affairs programs is done by most media monitoring services in the United States and allows for the searching of the text for client references. HDTV interoperability issues Originally there were two different kinds of closed captioning datastream standards specified by the US ATSC HDTV system; the systems specified by Line 21 and another more modern version encoded in MPEG-2, the EIA-708 standard DTV standard captioning improvements The EIA-708 specification provides for dramatically improved captioning Viewer-adjustable text size, allowing individuals to adjust their TVs to display small, normal, or large captions More text styles, including edged or drop-shadowed text rather than the letters on a solid background More text fonts, including monospaced and proportional spaced, serif and sans-serif, and some playful cursive fonts An enhanced character set with more accented letters and non-English letters, and more special symbols More text and background colors, including see-through backgrounds to optionally replace the big black block Higher bandwidth, to allow more data per minute of video History of Closed Captioning Open captioning Open captioning was the first form taken by television captioning in the earliest times, with the words printed directly on the screen. It all started with the French Chef on PBS in 1972 and was followed by other programs captioned by the WGBH Caption Centre. However, open captioning was purportedly not well accepted by the hearing community and this led to the development of closed captioning that are broadcast on Line 21 of the Vertical Blanking Interval, and are not visible unless decoding circuitry is utilized. Beginning of closed captioning Closed captioning begun in 1980 after the government had established a nonprofit National Captioning Institute to sell special decoders for closed captioning. A new National Captioning Institute was set up to avoid the potential conflict of having PBS through the WGBH Caption Center, offer captioning services for other networks. Closed captioning of television programs grew, but was not sufficient enough to satisfy deaf or hard of hearing people. Broadcasters did not want to caption more unless more decoders were sold; and many hard of hearing people did not want to buy decoders until more captioned programs were available. More decoders were in fact being purchased by hearing people, especially people learning English as a second language, who found they could benefit from the captions, than by deaf people themselves. Several factors kept decoder sales low: cost, limited availability, and not least, the reluctance of hard of hearing people to reveal their hearing loss by having a decoder attached to their television set. The Future of closed Captioning The Federal Communications Commission (FCC) enacted a rule on the implementation of Closed Captioning that will ensure all the TV programming distributors in the United States provides closed caption for Spanish language video programming by January 1, 2010. The Captioning Process The steps followed in the closed captioning process are: 1. The Master Copy Receiving the master copy of the videotape from the client. Creating a VHS work tape copy of the master with a time-code window. Making of an audio cassette. 2. Creation of the Transcript An accurate transcript is essential for captioning. If a transcript does not exist, it must be created. Transcripts can be submitted in the following formats: Text file. Captioner or transcriber. Internet (Via Internet file transfer). Fax (A text file can be faxed directly to the computer). Printed Script (A printed script is useful if it can be scanned accurately. The scanner works best with clean, even-toned, typed scripts). Disk (It can be in virtually any word processing application or an ASCII) Direct transcription: The captioner listens to the audio and changes the speech to text by typing what is heard. They can use a transcriber machine with auto backup or captioning software which advances, stops, and backs up the tape in the VCR or, use professional transcription equipment to speed up the process. Indirect transcription: The captioner retypes from a printed or faxed script, scans from a clean printed script, and imports from a word processing file that’s sent on disk or by e-mail. Indirect transcriptions must be compared with the original audio eventually. Most scripts received are not conformed to the audio and must be fixed. 3. Formatting Next, the transcript is: Divided into captions (The text is broken into short phrases which will become captions. Where possible, the split is usually by appropriate breakdown of sentence structure). Cleaned of extraneous text but maintains the meaning and essential vocabulary of the message. Music and sound effects are described. Checked for accuracy in the area of language mechanics, such as punctuation, grammar, spelling, and others. Normally text appears as two-line pop-up captions; however, some have the capacity to use from one to four lines in pop-up or roll-up fashion. Set the appearance of the captions. Add italics, underlining, colors, speaker identification, brackets around sound effects, music notes around song lyrics, and so forth. Some captioner does this as the script is entered; or, may go back and add it later. 4. Time-Coding A work tape is made. o Receiving the master copy of the videotape from the client. o Creating a VHS work tape copy of the master with a time- code window. o Making of an audio cassette. Matching of the Time code (A time code is assigned to each caption). This tells the caption when to appear on the screen. “Grabbed” time codes. (These are “Absorbed” as the tape plays, using the computer keyboard. In this step the captions may be moved up, down, left or right to determined where they will appear on the screen. One must ensure that necessary information is not covered by the captions and that the positioning hints at who the speaker is). 5. Presentation Rate Presentation rate control or reading speed This refers to the number of words appearing per minute for each caption. This depends on the grade level of the video and thus, a given presentation rate is assigned to a given captioning job. This is a key process and requires quite a bit of effort. The reading speed has to be correctly set in line with the timings of the tape. It is thus necessary to retime the tape whenever the reading speed had been set before the tape. The errors borne of captions starting too early or staying on too late is what necessitates the editing of the captions. There are also a number of rules that must be followed in order to preserve the integrity of the original script. 6. Positioning The position of the captions is to be inclined towards the speaker’s position onscreen. Otherwise, they are to be placed on the bottom lines at the center of the screen. 7. Checking and Revision Viewing A test-run of the video and the captions is to be done. They are to be played at the same time to test their appearance in the final captioned video. Checking and revision The captions are to be carefully checked for errors before being recorded. Automating the process can allow for auto-spelling checks, reading-rate checks, and technical timing error checks. The captioned video has to be checked for errors relating to caption positioning and timing. Crunching This is the process of fusing the time code to the captions. Any problems with conflicting time codes will cause the captions to move faster than the encoder will transmit and as a result, cause a gap, or incorrectly processed words. 8. Approved Copy Create a captioned approved copy of what will be encoded (for broadcast). 9. Encoding The captioning project is that transferred to a videotape using a caption encoder after the results have been approved. 10. Captioned Master The captioner then works closely with an engineer to produce the finished captioned videotape. The captioning file is transmitted from the computer to an encoder, where the original video, time code and new captions are recorded in the desired videotape format. Digital masters can be reproduced digitally using proprietary process for any digital format. How does it work? The following are steps representing a brief summary of the process of pre- recorded captioning: Reviewing of the recording and production of a program transcript. Segmenting of the transcript into individual captions, with correct time codes and positioning Reviewing of the end result for quality and accuracy. Encoding of the result into the final media (DVD, MPEG file, etcetera.) Captions can be placed on a video signal in one of two ways: Online (live) Offline (post-production) Online captioning This is done as an event occurs. Examples of online captioning are television news shows, live seminars, and sports events. Online captions can be done from a script, or actually created in real-time. Captions appear just a few seconds behind the action to show what is being said. A stenographer listens to the broadcast and types the words into a special computer program that adds the captions to the television signal. The typists have to be skilled at dictation and spelling and they have to be very fast and accurate at typing. Offline captioning This is done after the event occurs, in a studio. Examples of offline captioning include television game shows, videotapes of movies, and corporate videotapes (e.g., training videos). The text of the captions is created on a computer, and synchronized to the video using time codes. Caption writers use scripts and listen to a show's soundtrack so they can add words that explain sound effects. On a game show, for example, when there is no dialogue but there is laughter, the caption will say "Audience laughing." They are then transferred to the videotape before it is broadcast or distributed. Who uses closed captioning? Closed captioning can be extremely helpful in at least three different situations: It has been a great boon to hearing-impaired television viewers. Deaf people use closed captioning as a way of being able to watch television. Although they don’t hear what is being said, they read as to keep up with the action on the screen. It can also be helpful in noisy environments. For example, a TV in a noisy airport terminal can display closed captioning and still be usable. Turning the television volume up in such areas causes nothing more than cause confusion. Non native language speakers use captions to learn English or learn to read. Also in video conferences where some participants are non-native speakers, captioning helps these participants better understand the dialogue. In many cases, people can understand material in another language more easily by reading it than by hearing it. Those who are not deaf but are hard of hearing find that closed captioning is the best option. They may be able to turn the volume up loud in order to hear what is going on, but using closed captioning ends up being a better option. At the very least this can be used along with the sound as a way of making it easier to follow along. Statistically: 95 million Americans use captioning. 28 million Americans are hearing impaired. 30 million Americans are learning English as a second language. 27 million Americans are improving their literacy skills. 10 million Americans are school children learning to read. Powerful Closed Captioning and Subtitling Tools There are a number of useful captioning tools. The key tool used for captioning and subtitling is AutoCaption that gives you an elegant set of tools. The most useful of these tools are: Speech Recognition – AutoCaption works with the major systems. Proffer – Suggests each caption line or automatically breaks a transcript or script into captions. No more picking every single word in each caption! Rules – You make the rules for what each proffer suggests. Reading-Rate – Graphically see how fast the viewer has to read each caption. Smoother – Automatically adjusts appearance times for an even reading rate. Grab the in and out points for off-screen narration and you're done! Random-Access – Work on digitized video and eliminate expensive tape decks. Edit Detection – Captions which respect edits are the hallmark of a superior captioner. It's effortless too. Speech Sync – Synchronize captions to the moment the image begins to speak. Ripple – Adjust appearance times by a fixed amount. Previewing – See the captions on the video while you're working. Foreign Languages – Complete support for UNICODE means you can work in all languages – simultaneously! Free Translator Support Software – Translate captions without having to re-do the timing, unless you want to. Spell Checking – You can even build your own customer specific dictionary extensions for terms-of-art or proper names. Macros – Build a library of macros specific for each client or type of captioning. Multi-channel Captioning – Caption all closed caption channels or all 32 DVD subtitle channels. Time Compression – Instantly re-time captions when a show's run time is electronically compressed or stretched. Error Manager – Speed clean-up and fix-up with continuous error checking, error explanations, and a handy way to skip from error to error. Use Video Files – Schedule captions from video files (MPG, ASF, AVI, etc.) or you can even use an ordinary consumer video deck without SMPTE time code. Free Digitizing Software – Make digital files to caption from without tying up AutoCaption! Make DVD Caption Assets – Make closed caption and subtitling asset files for your DVD authoring system. Recover Closed Captions From Video – AutoCaption accepts data recovery files. Free Approve Caption – Internet caption viewer can be used anywhere to preview captions. Closed caption equipment (software and Hardware) There are two stages to offline captioning: Editing (Creating the captions) Encoding (Placing them on the videotape) These stages have difference software and hardware requirements. Editing Editing requires that you have a computer with captioning software. Pick the software first, and then buy the appropriate computer to run it, as hardware requirements vary from software vendor to software vendor. The computer will have to have; A video source such as a computer-controlled video tape recorder (VTR) A way to tell where it is on the tape (such as a time code reader) A way to display the video (such as a full-motion video card in the computer, or an extra television monitor) Some editing systems require encoders or character generator decoders, and some are digital, requiring the videotape only to get the video into the system. Encoding This stage requires a computer with the caption encoding software, which may or may not be the same software you used for editing. You will also need; Two VTRs (One to play the original master tape, and one to record the new captioned submaster) A caption encoder will be required to actually place the captions on the tape. Timecoding for synchronization will be required, and there are a number of ways to accomplish this. The best way is to get the specifications for what you need from your caption software vendor Unless you already have a video production facility, it can get rather expensive to acquire all the equipment you'll need to make a finished captioned media. Working with broadcast quality tape media can get expensive, because you'll need: A broadcast video source A broadcast video recorder Alignment and monitoring equipment DVD Authoring DVD technology can be a bit simpler unless you need to digitize and author the master DVD file. To author a DVD you need: A high resolution digitized media file And you need a DVD authoring system(The authoring system takes the video, audio, and AutoCaption caption files and puts them all together into a master DVD image file). The most cost effective route is to let your client do the encoding. Give them a DCAP file and all they need is a caption inserter suitable for the type of video supplied. Closed captioning for the deaf The National Association of the Deaf advises that all producers of video, television broadcasts and film, including commercials and information presented on the Internet, to caption their offerings. This section on captioning outlines the NAD's views on a wide variety of captioning technologies and advises consumers how they may file complaints about non-captioning and poor captioning. As the legal requirements on closed captioning become effective, deaf or hard of hearing people are urged to be alert for inadequate captioning. When a broadcaster is not meeting its responsibilities, they are urged to file complaints with the enforcement agencies. Federal laws pertaining to closed captioning There are a number of laws pertaining to captioning: Television Decoder Circuitry Act of 1990 As of July 1993, the Federal Communications Commission (FCC) began requiring all analog televisions manufactured in the US and 13” or larger to have the ability to decode closed captioning. Digital television receivers were also required to meet this standard beginning in July 2002. Americans with Disabilities Act (ADA) of 1990 The ADA requires closed captioning of all public service announcements distributed by the federal government. Telecommunications Act of 1996 Congress passed legislation in 1996 that required all television program operators to provide the closed captioning for their programs. The FCC has determined requirements that have increased incrementally over the years to ensure more programs are available with closed captioning. The programs of highest importance are those pertaining to emergency announcements and news. Rehabilitation Act - Section 508 Accessibility Section 508 of the Rehabilitation Act as strengthened by the Workforce Investment Act of 1998 requires that Federal agencies make their electronic and information technology (EIT) accessible to people with disabilities, including employees and the general public. The requirements of Section 508 apply to an agency's procurement of EIT, as well as to the agency's development, maintenance or use of EIT. All training and informational video and multimedia productions that support the agency's mission regardless of format, must be open or closed captioned if they contain speech or other audio information necessary for the comprehension of the content. All training and informational video and multimedia productions that support the agency's mission regardless of format, must include an audible description of the video content if they contain visual information necessary for the comprehension of the content. Glossary of Closed Captioning Terms and Acronyms Acronyms AA Average Audience - used for measuring TV viewership AARP American Association of Retired Persons ABES Association for Broadcast Engineering Standards ADA Americans with Disabilities Act ADI Area of Dominant Influence AEA Actors Equity Association AEA American Electronics Association AFTRA American Federation of Television & Radio Artists AITS Association of Independent Television Stations ALDA Association of Late Deafened Adults ASL American Sign Language Basys A newsroom computer system BNC Bayonet Connector (for coaxial cable) Caption 21 Script-based captioning system from Basys CAPtivator Online Real-time (live) captioning software from Cheetah Systems CAPtivator Offline Post-production captioning software from Cheetah Systems CATV Cable Television (originally Community Antenna TV) CBC Canadian Broadcasting Corporation CC Closed-Captioned CCE/PC Closed-Caption Encoder for the PC (card made by SoftTouch) CE Chief Engineer (Chief Station operator) Cheetah Systems Manufacturer of captioning software & systems CHUT Cable Households Using Television decoder Decoder A device that displays closed captions "hidden" in the VBI DTV Digital Television EDTV Extended Definition Television EEG Manufacturer of professional caption encoders/decoders Encoder A device that "hides" captions in the VBI ENG Electronic News Gathering FCC Federal Communications Commission FTC Federal Trade Commission HBI Horizontal Blanking Interval HDTV High Definition Television HOH Hard-of-Hearing LTC Longitudinal Time Code (SMPTE timecode on audio track) Line 21 Area of VBI containing closed-caption text Live-display Hand-timing captions from a script during live programming MOP Minute of Program MSA Metro Survey Area MSI Market Statistics Inc. MTBF Mean Time Between Failure(s) MTBR Mean Time Between Repair(s) NAB National Association of Broadcasters NewStar Newsroom computer system from Dynatech NCI National Captioning Institute (captioning company in VA) NSI Nielsen Station Index O&O Owned & Operated (a TV station owned by its network) PA Public Affairs Paint-on Captions being "drawn" a letter at a time anywhere on screen PBS Public Broadcasting Service PD Program Director - Production Director Pop-on Captions appearing all at once anywhere on TV screen POTS Plain Old Telephone Service - used to refer to ordinary phone lines PPV Pay per View PSA Public Service Announcement RCA connector Connector used for home video and audio equipment Real-time Captions produced using a stenocaptioner RGB Red-Green-Blue (for video signals on three wires) RGB/Sync Red-Green-Blue with synchronization signal (four wire video) Roll-up Two- to four-line captions scrolling on screen RTNDA Radio & Television News Directors Association SAP Second Audio Program on TV subcarrier SBE Society of Broadcast Engineers SCTE Society of Cable Television Engineers SECAM Sequential Coleur Avec Memoire SMPTE Society of Motion Picture & Television Engineers SMSA Standard Metropolitan Statistical Area SoftTouch Manufacturer of plug-in caption encoders for personal computers SVHS Super VHS - a 1/2" videotape format TBC Time Base Corrector (for "cleaning up" video signal) TDCA Television Decoder Circuitry Act TDD Telecommunications Device for the Deaf (used as synonym for TTY) TeleCaption Teletext Captioning standard used in UK & parts of Europe Timecode Unique time identifier "stamped" on each frame of video TT Text Telephone (obsolete synonym for TTY - not used) TTY Teletypewriter (see a lso TDD U-Matic A 3/4" videotape format VBI Vertical Blanking Interval - the "blank" lines of video picture VCR Video Cassette Recorder VITC Vertical Interval Time Code VPS Viewers per Set VPVH Viewer per Viewing Household VTR Video Tape Recorder Terms Captioning This is the practice of converting the narration, dialogue, music and sound effects of a video production into text that is displayed on a television screen. The captions are typically white upper-case letters against a black background. Prerecorded (Off-line) Captioning The preparation of captions for recorded programming so that, at the time of air or tape playback, the captions are a part of the videotape. Appearance of captions is usually "pop-on" but could also be "roll-up." Captions are typically placed in the upper or lower third of the television screen. Pop-on Captions A phrase or sentence appears on the screen all at once – not line by line – stays there for a few seconds and then disappears or is replaced by another full caption. The captions are timed to synchronize with the program and placed on the screen to help identify the speaker. Pop-on captions are used for prerecorded captioning. Center Placement Pop-On Captions Pop-on captions are centered at the bottom third of the TV screen. Their placement is similar to subtitles although they are displayed as captions in white letters in a black box. Speaker changes are noted by a dash. Roll-up Captions Roll-up captions roll onto and off the screen in a continuous motion. Usually two to three lines of text appear at one time. As a new line comes along, it appears on the bottom, pushing the other lines on the screen up. Roll-up captions are used for all live captioning and can also be used for prerecorded captioning. Timed Roll-Up Captions For prerecorded programming, roll-up captions can be timed to be closely synchronized with the audio. Live (On-line) Captioning Captioning that is provided at the time of program origination. "Real-time," "live- display" and a combination of the two are all methods of on-line captioning. Appearance of captions is "roll-up." Real-time Captioning This is the method of captioning in which captions are simultaneously prepared and transmitted at the time of origination by specially trained real-time captioners using a stenotype machine. Real-time Dictionary This is a computerized dictionary that is comprised of the phonetics and their corresponding English that the captioner uses to build words and create punctuation. Real-time captioners write phonetically what they hear. Similar to playing chords on a piano, multiple keys are depressed on a steno machine to create different word combinations. No two captioners write exactly the same way, so each has a custom dictionary. Live-display Captions Live-display captioning is used when an accurate script and/or videotape is available prior to the time a program is telecast. Captions are prepared in advance and stored on a computer disk. As the program is telecast, a captioner pushes a button on the captioning system to display each caption. The roll-up captions appear line-by-line and are synchronized with the program audio as closely as possible. Closed Captions These are captions that can only appear with the use of a decoder. The decoder may be either attached to a TV or built into TV's made after July 1993. Closed captioning allows caption users to enjoy the same broadcast and recorded video materials that other television viewers enjoy. Closed-caption information is carried in Line 21 of the vertical blanking interval of the television signal. Open Captions These are the captions that are visible without using a set-top decoder or a TV with a built-in decoder chip. When a video is open captioned, the captions are permanently part of the picture. Closed Caption Decoder This is a small electronic device that decodes the captioning signal and causes captions to appear on the screen. In the 1980's and early 1990's, closed caption decoders were the major means by which consumers could watch captioned television. Since July 1, 1993, all television sets with screens 13 inches or larger manufactured for sale in the United States must have a built-in decoder chip. Caption File This is a computer file that stores a program's caption information including the text, timing and placement information. The caption file is used in conjunction with an encoder to create the captioned submaster. Encoding The process of inserting the caption data into the television signal on Line 21 Encoder A device that electronically inserts the caption data into the TV signal on Line 21 Line 21 The television signal is comprised of 525 lines. The vertical blanking interval encompasses Line 1 through 21. The caption information resides on Line 21, and active video starts on Line 22. Time-code An electronic signal embedded in a videotape that discretely identifies each frame of video. Master This is the original, first-generation videotape of the final version of a program. The master is the source videotape used to create a captioned "submaster." Submaster Any duplication created from the master videotape. The captioned videotape is a submaster of the original. Automatic Live Encoding (ALE) When production schedules are tight, this is an alternate means of transmitting or displaying captions. Automatic live encoding makes use of the same caption creation techniques used in prerecorded captions, but a different method is used to trigger the data into Line 21 of the television signal. The captioned data is loaded into the computer, and the internal clock within the computer is used to trigger the captions as opposed to using time-code from the program videotape. A manual trigger is used to start the transmission of data between the computer and the smart encoder. The display of automatic live encoding is pop-on, the same as used for prerecorded captions. Subtitles Permanent on-screen text that represents the recitation and dialogue of a program m. Subtitles are created with a character generator; no decoding capability is required for viewing them. Subtitles are normally in upper and lower case letters and do not appear in a black background. Also, subtitles are characteristically placed at the mid bottom of the screen. Reformat The practice of revising previously captioned programs for rebroadcast, necessitating the retiming and/or editing of the caption content to synchronize it to the edited video and audio.
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