Glossary - Axis 262 User Manual

AXIS 262 - Glossary
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Glossary

Active Speaker - a speaker with a built-in power
amplifier.
ActiveX - A control (or set of rules) used by a browser.
ActiveX controls are often downloaded and installed
automatically as required.
ADPCM - Adaptive Differential Pulse Code Modulation.
Predicts the analog signal digitally and the difference is
coded.
AMC - AXIS Media Control. The control required for
viewing video images in Internet Explorer. Installs
automatically on first use.
API - Application Programming Interface. The Axis API
can be used for integrating Axis products into other
applications.
ARP - Address Resolution Protocol. A protocol for
assigning an IP address to a physical device address that
is recognized in the local network. The ARP command can
be used to set the IP-address for your product.
ARTPEC - Axis Real Time Picture Encoder - used for
video image compression.
Axis 262 Commander - ActiveX component used in the
Main View.
CCD - Charge Coupled Device. CCD is one of the two main
types of image sensors used in digital cameras. When a
picture is taken, the CCD is struck by light coming
through the camera's lens. Each of the thousands or
millions of tiny pixels that make up the CCD convert this
light into electrons.
CGI - Common Gateway Interface. A set of rules (or a
program) that allows a Web Server to communicate with
other programs.
Client/Server - Describes the network relationship
between two computer programs in which one, the client,
makes a service request from another - the server.
dB (Decibels) - A unit to measure sound level changes. A
3dB change is the smallest level change we can hear. A
3dB change is actually twice or half the audio power
level. A gain of 0dB will leave the signal level unchanged.
DC-Iris - This special type of iris is electrically controlled
by the Axis camera, to automatically regulate the amount
of light allowed to enter.
De-interlacing - An image quality improvement process
taking a stream of interlaced frames and converting it to a
stream of progressive frames.
DNS - The Domain Name System (DNS) locates and
translates Internet domain names into IP (Internet
Protocol) addresses.
Ethernet - A widely used networking standard.
ETRAX - Axis' own microprocessor.
Firewall - A virtual barrier between a LAN (Local Area
Network) and other networks, e.g. the Internet.
FTP - File Transfer Protocol. Used for the simple transfer
of files to and from an FTP-server.
FPS - Frames per second.
Full duplex - Transmission of data, e.g. audio, in two
directions simultaneously.
G.711 - G.711 is the international standard for encoding
telephone audio on 64 kBit/s channel. It is a pulse code
modulation (PCM) scheme operating at 8 kHz sample rate.
G.726 - Frequently used speech-compression algorithm in
telecommunications due to its high perceived speech
quality and low resource requirements.
HAD - Hole Accumulation Diode. A HAD CCD design
allows for more light to reach the imager, which reduces
video noise to improve signal-to-noise ratio by up to 6dB
(2x better than a standard CCD imager). Particularly
effective when shooting in dark situations.
Half duplex- A half duplex link can communicate in only
one direction, at a time. Two way communication is
possible, but not simultaneously. Walkie-talkies and CB
radios mimic this behavior in that you cannot hear the
other person if you are talking.
HTML - Hypertext Mark-up Language. Used widely for
authoring documents viewed in web browsers.
HTTP - Hypertext Transfer Protocol. The set of rules for
exchanging files (text, images, sound, video, and other
files) on the World Wide Web.
Intranet - A private network limited to an organization or
corporation. Usually closed to external traffic.
IP - Internet-Protocol. See TCP/IP.
IP address - A unique number used by a network device,
to allow it to be identified and found on the network. The
32-bit IP address is made up of four groups (or quads) of
decimal digits separated by periods. An example of an IP
address is: 192.168.0.1
ISMA - Internet Streaming Media Alliance
JPEG - A standard image format, used widely for
photographs. Also known as JPG.
LAN - A local area network (LAN) is a group of computers
and associated devices that typically share common
resources within a limited geographical area.
Linux - A popular operating system, which is "open
source" and practically free of charge.
Lux - A standard unit for the measurement of light, where
1 Lux equals the light emitted from a single candle at a
distance of one meter.
Mbit/s - Megabits per second. A unit for measuring