Closed captioning can be extremely helpful in at least three different situations :
Closed captioning is embedded in the tv set signal and becomes seeable when you use a particular decipherer , either as a separate appliance or built into a goggle box set . The decipherer lets viewers see caption , normally at the bottom of the screen door , that will tell them what is being said or try on their favorite TV shows . Since 1993 , television sets with screen of 13 inches or more that are sold in the United States must have built - in decoders , under the Television Decoder Circuitry Act . Set - top decoders are available , too , for older TV set .
The captions are obliterate in theline 21 data areafound in the vertical blanking interval of the television sign . If you have read the article entitledHow Television Worksor thequestion on the volt - chip , then you know about the blanking interval . It is the surface area of the television signaling that tells the negatron gun to shoot back up to the upper left-hand corner of the blind to start paint the next frame . Line 21 is the line of credit in the upright blanking interval that has been assign to captioning ( as well as time and V - chipping selective information ) . Each anatomy of picture can transmit two reference of captioning data ( or extra commands that ascendance color , popups , etc . )
Many shows and commercial message convey subtitle nowadays . Older platform made before captioning became widespread have captions added for their reruns . Captioned programs are notice in TV listings by " milliliter " . If you have a set with a decipherer built in , you’re able to turn on the captioning – check your set ’s manual of arms for the instructions .
Some show are captioned in real sentence . That is , during a live broadcast of a special event or of a news program , captions appear just a few s behind the action to show what is being said . A shorthand typist mind to the broadcast and types the words into a exceptional computer program that contribute the caption to the television sign . The typists have to be skilled at dictation and spelling and they have to be very fast and exact at typing .
Other shows carry caption that get added after the show is produced . subtitle writers use hand and listen to a show ’s soundtrack so they can add words that explicate sound effects . On a plot show , for example , when there is no duologue but there is laughter , the caption will say " Audience laughing . "
Here are several interesting link :
