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EAV:
End of active video in component digital systems.
EBU:
European Broadcasting Union. An organization of European broadcasters
that, among other activities, produces technical statements and
recommendations for the 625/50 line television system. CP 67, CH- 1218
Grand-Saconnex GE, Switzerland. Tel: 011-41-22-717-2221. Fax:
011-41-22-717-2481. Email: ebu@ebu.ch. Internet: www.ebu.ch.
ECC:
Error Check and Correct. A block of check data, usually appended to
a
data packet in a communications channel or to a data block on a disk,
which allows the receiving or reading system both to detect small
errors in the data stream (caused by line noise or disk defects) and,
provided they are not too long, to correct them.
E-Cinema
(also D-Cinema): Electronic cinema. Typically the
process of using video at 1080/24p instead of film for production,
post production and presentation.
EDH:
Error detection and handling for recognizing inaccuracies in the
serial digital signal. It may be incorporated into serial digital
equipment and employ a simple LED error indicator.
Electronic
Programming Guide
(EPG): An application that
provides an on-screen listing of all programming and content that an
interactive television service subscriber or digital television viewer
has available to them. See also: PSIP.
Embedded
audio: Digital audio that is multiplexed and carried within an SDI
connection--so simplifying cabling and routing. The standard (ANSI/SMPTE
272M-1994) allows up to four groups each of four mono audio channels.
Generally VTRs only support Group 1 but other equipment may use more,
for example Quantel's Clipbox server connection to an edit seat uses
groups 1-3 (12 channels). 48 kHz synchronous audio sampling is pretty
well universal in TV but the standard also includes 44.1 and 32 kHz
synchronous and asynchronous sampling. Synchronous means that the
audio sampling clock is genlocked to the associated video (8,008
samples per five frames in 525/60, 1,920 samples per frame in 625/50).
Up to 24-bit samples are allowed but mostly only up to 20 are
currently used. 48 kHz sampling means an average of just over three
samples per line, so three samples per channel are sent on most lines
and four occasionally--the pattern is not specified in the standard.
Four channels are packed into an Ancillary Data Packet and sent once
per line (hence a total of 4 x 3 = 12 or 4 x 4 = 16 audio samples per
packet per line). |
Enhancements:
Producers add these to interactive and digital television, as well as
other digital content to enhance program material. Examples are
supplementary text and graphics that add more depth and richness, or
links to reach a Web site, as is done using TV Crossover Links. In
analog, the vertical blanking interval (VBI) is used to broadcast
enhancements, while in digital, the enhancements are part of the ATSC
MPEG-2 stream. Enhancements can be created using industry-standard
tools and technologies, like HTML and the ECMA Internet Scripting.
Encryption:
The process of coding data so that a specific code or key is required
to restore the original data. In broadcast, this is used to make
transmissions secure from unauthorized reception as is often found on
satellite or cable systems.
Error
concealment:
In digital video recording systems, a technique used
when error correction fails. Erroneous data is replaced by data
synthesized from surrounding pixels.
Error
correction:
In digital video recording systems, a scheme
that adds overhead to the data to permit a certain level of errors to
be detected and corrected.
Error
detection:
Checking for errors in data transmission. A calculation
is made on the data being sent and the results are sent along with it.
The receiver then performs the same calculation and compares its
results with those sent. If an error is detected the affected data can
be deleted and retransmitted, the error can be corrected or concealed,
or it can simply be reported.
Error
detection and handling:
See: EDH.
Essence:
The actual program (audio, video and/or data) without metadata.
See also: Metadata.
Ethernet
(IEEE 802.3): A type of high-speed network for
interconnecting computing devices. Ethernet can be either 10 or 100
Mbps (Fast Ethernet). Ethernet is a trademark of Xerox Corporation,
Inc.
Extended
Studio PAL: A 625-line video standard that allows processing of
component video quality digital signals by composite PAL equipment.
The signal can be distributed and recorded in a composite digital form
using D2 or D3 VTRs.
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