Captioning: The process 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: 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: 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: 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: 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: 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: 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: 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 narration and dialogue of a program. Subtitles are created with
a character generator; no decoding capability is required for viewing
them. Subtitles are usually in upper- and lower-case letters and do
not appear in a black background. Also, subtitles are typically placed
at the bottom center of the screen.
Reformat: The process of revising previously captioned
programs for rebroadcast, requiring the retiming and/or editing of caption
text to synchronize it to the edited video and audio.
