tain ways. A full-screen NTSC image is comprised of 480
visible lines and a total of 525 lines. 60 half-images are
displayed per second. Compared to PAL, the system is
more susceptible to colour errors.
PAL
Phase Alternating Line – European colour TV system.
Uses 576 visible image lines. Together with the lines
used for signal management, a full-screen image is com-
prised of 625 lines. 50 half-images are displayed per
second. The phase position of the colour signal changes
from line to line in the image.
PANEL
Interior of a flatscreen display (e.g. LCD or plasma
panels).
PC
Personal Computer – Can be used as a remote site,
either with the software supplied or over a browser.
Pixel
Short for “picture element”, the smallest unit for digital
image transmission or display.
PIP
Picture in Picture – Where two signal sources are shown
on the screen at the same time. The second signal
source is stored above the first.
PPPoE
PPP over Ethernet (point-to-point protocol)
Network transmission method used for establishing a
connection over dial-up lines. Used in ADSL connections,
for example.
PROGRESSIVE
Method for displaying, storing or transmitting moving im-
ages in which all the lines of each frame are drawn in se-
quence. This is in contrast to the interlacing used in tradi-
tional television systems.
PTZ
Pan-Tilt-Zoom
Pan, tilt and zoom function on motor-driven cameras.
RESOLUTION
Normal PAL television systems show images in 576 lines,
normally with 768 pixels. HDTV works with at least 1280 x
720 pixels.
SCREEN SIZE
Size of the display from the bottom-left corner to the top-
right corner in inches or centimetres.
Browser
Program for viewing websites on the Internet.
USB
Universal Serial Bus
Serial bus connection, used for connecting media whilst
in operation. Maximum data rate for USB 2.0: approx.
320 Mbit/s (approx. 40 MB/s).
VGA
Video Graphics Array – Standard interface for analogue
video signals in PCs (primarily deals with RGB signals).
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