Glossary
© 2013 Harmonic Inc.
381
Ellipse 3000 r.3.0, Rev. B
GMT
Greenwich Mean Time. The time in Greenwich, England, which is the location of the prime
meridian (0 degrees longitude). All time zones are referenced to this meridian.
GOP
Group Of Pictures. An MPEG-2 video coding structure, a GOP may be either “open” or
“closed”. Note that AVC does not define a GOP by itself, but has equivalent structural
constructs.
Grid
Grid is a lightweight and highly scalable top layer add-on to the NMX’s as an enterprise
solution. It provides an efficient means to manage multiple NMX’s through an easy-to-use
interface. It addresses the needs for consolidated network management solutions for large
systems where the typical size of video compression networks has grown considerably.
Grid Enabled
The check box option is in the
Options > Grid
page from the NMX application. This check box
is used to enable/disable the Grid NMX. Only Grid enabled NMX’s can be added into the Grid
route group.
H
HD
High Definition.
HDD
Hard disk drive.
HDM
Harmonic Digital Mosaic.
HE AAC
High Efficiency Advanced Audio Codec.
headend
The distribution point in a TV system.
header
Several bytes at the beginning of a packet that determine the identification of the packet,
possibly the type of data and other attributes within the packet.
Hertz (Hz)
A unit of frequency defined as one cycle per second. Abbreviated Hz.