Glossary
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Glossary
Technical terms used
16:9
Cinema orientated aspect ratio for wide-screen displays.
Screen diagonal
Size information for displays: Distance between the
bottom left-hand corner to the top right-hand corner
– in
inches or centimetres.
Browser
Program for viewing websites on the World Wide Web.
CIF
'Common Intermediate Format'.
Originally intended for conversion of PAL to NTSC
standard. CIF equates to a video resolution of 352 x 288
pixels, 2 CIF 704 x 288 pixels, 4 CIF 704 x 576 pixels.
DDNS
'Dynamic Domain Name System Entry'
A network service that keeps and updates the IP
addresses of its clients in a database.
DHCP
'Dynamic Host Configuration Protocol'
A network protocol that enables the automatic
incorporation of devices (clients) into existing networks.
As such, DHCP servers (such as internet routers)
allocate the IP address, the network mask, the gateway,
the DNS server and, if necessary WINS server
automatically. The client only has to be set to obtain the
IP address automatically.
Domain
Domains (name space) that identify Internet pages (e.g.
www.abus-sc.de).
Dual stream
Dual stream designates a video transmission method. A
high resolution recording is made along with a low
resolution transmission, e.g. via the network.
DVR
Digital Video Recorder; a device for recording various
video and audio sources (analogue, digital). The data is
compressed for recording and stored on hard disk drives.
CVBS
"Colour, Video, Blanking and Synchronisation" signal.
The most simple variant of video signals, also called
"Composite Signal". Picture Quality is comparatively low.
H.264
(MPEG-4 AVC); standard for high-efficiency compression
of video signals. Used in such things as Blu-ray discs or
video conferencing systems.
HDD
'Hard Disk Drive', hard disk (magnetic disk store)
Digital data store in computers or NVRs.
GIGABYTE
Unit of storage capacity for storage media (HDD, USB,
SD/MMC cards).
HDVR
Hybrid DVR, DVR for recording from analogue cameras
and network cameras.
http
'Hypertext Transfer Protocol';
A process for data transfer across networks. Mainly used
for the presentation of websites in a browser.
INTERLACED
Line skip procedure
IP address
An address on a computer network based in the internet
protocol (IP), this enables various devices to be
addressable on the network and individually accessible.
JPEG
Low-loss compression process for photos. Most digital
cameras store their pictures in JPEG format
MPEG
Abbreviation for Moving Picture Experts Group. This is
used as an international standard for the compression of
moving pictures. On some DVDs the audio signals are
compressed and recorded in this format.
NTP
Network Time Protocol
A process for time synchronisation across networks. Also
SNTP (Simple Network Time Protocol) that represents a
simpler form.
NTSC
Colour television standard in the USA. The process
differs in certain details from the European PAL system:
An NTSC full screen consists of 480 visible lines and a
total of 525 lines. Sixty half images are displayed per
second. Compared with PAL, the system is more
susceptible to colour distortions.