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* Aspect Ratio:
It is the ratio of the width of the screen to the height. The two relevant
digital TV formats are 16:9 (wide screen) or 4:3 (the traditional screen
ratio). 16:9 is ergonomically more suitable for human’s eye.
* AFD
Abbreviation for “Active Format Descriptor”. A format code which
can be used to send information about the “protected” area inside
a widescreen picture which may be cut off for viewing on non-
widescreen TV displays. Used for Aspect Ratio selections.
* Composite Video:
There are three elements of the video system: First - the “active
video” which means the picture to be displayed on the screen and its
associated colors. Second - the “sync” decides where to place each
pixel on the screen. Third - the “blanking” tells the display when to
turn off the electron beam so no retrace across the screen. These
three elements combined together is called “composite video” when
connecting to a display through connectors.
* DVB:
Abbreviation for “Digital Video Broadcasting”. An international
organization created in October 1993, whose primary objective is
to achieve a common framework for all technical platforms of digital
broadcasting systems including DVB-C (cable), DVB-S (satellite),
DVB-T (terrestrial), DVB-MC (MMDS), DVB- CS (SMATV).
* EPG:
Abbreviation for “Electronic Programme Guide”. It is software that
enables viewers to navigate through the large number of channels
offered by digital TV broadcaster and select the desired services.
* Frequency:
The property of a signal which is measured in cycles per
second(=Hertz).
* Letterbox:
The picture with aspect ratio 16:9 in a 4:3 TV screen with blank
lines on top and bottom. It is the means to watch a wide screen TV
programme on a 4:3 TV screen.
* OSD:
Abbreviation of “On Screen Display”, used in digital set top box. OSD
is comprised of a main menu and many submenus with lots of options
of functions inside.
* PAL:
Stands for “Phase Alternating Line”, the European video standard
which has the image format of 4 by 3, 625 horizontal lines, 50 Hz and
a total 8 MHz of video channel width.
* Y/Pb/Pr:
Component Video. It is better than S-Video and Composite Video in
terms of picture quality.
*HDMI:
High Definition Multimedia Interface transmits High Resolution
uncompressed Video and Audio over a single cable between a Digital
Receiver and a High Definition Television Display.
*HD:
High Definition Television (HDTV) offers wide-screen 16:9 television
with HD broadcasts regularly including enhanced Surround Sound
Audio. HDTV broadcasting is increasingly common in two variants:
720p and 1080i. 720p is a progressive system with 1280x720 Pixels
in each frame. 1080i is an integrated system where the 1920 Pixels
are divided into two fields for more efficient transmission.
Glossary
