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User Guide and Technical Manual
Term
Defi nition
GOP
In MPEG encoding, a Group of Pictures [GOP] speci
fi
es the order in which
intra-frames are arranged. The GOP is a group of successive pictures within an
MPEG-coded
fi
lm and/or video stream. Each MPEG-coded
fi
lm and/or video
stream consists of successive groups of pictures.
GSM Modem
Global System for Mobile Communications Modem
A GSM Modem is a specialized type of modulator/demodulator that accepts
a SIM [Subscriber Identity Module] card and operates over a subscription
to a mobile operator, as a mobile phone functions. When a GSM modem is
connected to a digital device, it uses the GSM modem to communicate over
the mobile network. While GSM modems are most frequently used to provide
mobile Internet connectivity, many of them can also be used for sending
and receiving SMS [Short Message Service (e.g. text message)] and MMS
[Multimedia Messaging Service] messages.
Guard Interval
A method used to prevent interference among distinct transmissions.
H.264
H.264/MPEG-4 Part 10 or AVC [Advanced Video Coding] is a standard for video
compression and is currently one of the most commonly used formats for the
recording, compression and distribution of high de
fi
nition video.
HD
High De
fi
nition [video]
HD-SDI
High De
fi
nition Serial Data Interface
A serial communications interface operating at 1.5 Gbit/sec.
HSDPA
High-Speed Data Packet Access
HSPA+
Evolved High-Speed Data Packet Access
IFB
Interruptible foldback [IFB], is an intercom cueing system used to monitor and
intercede in television and radio broadcasts, public speaking,
fi
lm and video
production and other such endeavors.
The IFB intercom circuit consists of a mix-minus program feed sent to a
presenter’s wired or wireless in-ear monitors [IEMs] through a telephone or
radio receiver. This feed can be interrupted and replaced by a producer’s or
director’s intercom microphone. For example, on a television news program, a
producer can talk to the news anchors, to tell them when they are live on the air
and to begin reading the news, or when to take a break.
In electronic news gathering [ENG], IFB transmission can be sent through a
telephone hybrid, the station’s Multi-channel Television Sound [MTS] PRO
channel during live remote broadcasts, or through some other return link in a
broadcast auxiliary service.
All signals arrive on site with a time delay as they travel through a wire, or
during the conversion to radio frequency and then back to electronic audio, or
in the conversion from analog to digital signal and back again to the analog
realm. To achieve the mix-minus program to the IFB, certain audio elements that
originate remotely from the mix point will be eliminated from the mix sent back to
the remote site to avoid an echo.
