Glossary – Axis Communications 241SA User Manual
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AXIS 241QA/AXIS 241SA - Glossary
Glossary
Active Speaker - a speaker with a built-in power
amplifier.
ActiveX - ActiveX is a standard that enables software
components to interact with one another in a networked
environment, regardless of the language(s) used to create
them. Web browsers may come into contact with ActiveX
controls, ActiveX documents, and ActiveX scripts.
ActiveX controls are often downloaded and installed
automatically as required.
AF (Autofocus) - A system by which the camera lens
automatically focuses on a selected part of the subject.
AMC (AXIS Media Control) - AMC is the ActiveX
component required to view moving images from an Axis
video device in Internet Explorer. The component is
installed automatically on the viewing computer on first
use. Once installed, AMC can be configured from
Windows Control Panel.
Analog video camera - The signal from an analog video
camera is viewed directly on e.g. a monitor in the analog
system, which depends on traditional analog cabling.
Alternatively, the signal can be digitized with the use of a
video server, and can then be made available over a data
(IP) network.
Angle - The field of view, relative to a standard lens in a
35mm still camera, expressed in degrees, e.g. 30°. For
practical purposes, this is the area that a lens can cover,
where the angle of view is determined by the focal length
of the lens. A wide-angle lens has a short focal length and
covers a wider angle of view than standard or telephoto
lenses, which have longer focal lengths.
API (Application Programming Interface) - An API is a
set of routines, protocols, and tools for building software
applications. A good API makes it easier to develop a
program by providing all the required building blocks.
The Axis VAPIX API allows Axis products to be
integrated into other applications.
ARP (Address Resolution Protocol) - This protocol is used
to associate an IP address to a hardware MAC address. A
request is broadcast on the local network to discover the
MAC address for an IP address.
ARTPEC (Axis Real Time Picture Encoder) - A chip
designed by Axis for image compression. ARTPEC
supports a range of CCD and CMOS sensors, built-in
functionality for sharpening, backlight compensation,
noise reduction and white balance, support for multiple
Motion-JPEG streams, support for MPEG-4 part 2, up to
30 frames/second from 4 simultaneous video sources and
real-time compression of up to 45 Megapixels/second.
ASIC (Application Specific Integrated Circuit) - A circuit
designed for a specific application, as opposed to a
general purpose circuit, such as a microprocessor.
Aspect ratio - A ratio of width to height in images. A
common aspect ratio used for television screens and
computer monitors is 4:3. High-definition television
(HDTV) uses an aspect ratio of 9:16.
Autoiris (DC-Iris) - This special type of iris is electrically
controlled by the camera, to automatically regulate the
amount of light allowed to enter.
AVI (Audio Video Interleave) - A video format that
supports simultaneous playback of audio and video.
AXIS Internet Dynamic DNS Service - This free service
provides an Axis network product with a unique DNS or
domain name (URL address), which can then be used
instead of an IP address to access the product from a web
browser.
AXIS IP Utility - A tool for discovering and setting IP
addresses for Axis network devices. AXIS IP Utility is
supplied free of charge by Axis.
AXIS Camera Management - A powerful and efficient
installation and management tool for Axis network video
products. The tool can automatically find and set IP
addresses, show connection status and manage firmware
upgrades of multiple devices.
Bitmap - A bitmap is a data file representing a
rectangular grid of pixels. It defines a display space and
color for each pixel (or "bit") in the display space. This
type of image is known as a "raster graphic." GIFs and
JPEGs are examples of image file types that contain
bitmaps. Because a bitmap uses this fixed raster method,
it cannot easily be rescaled without losing definition.
Conversely, a vector graphic image uses geometrical
shapes to represent the image, and can thus be quickly
rescaled.
Bit rate - The bit rate (in kbit/s or Mbit/s) is often referred
to as speed, but actually defines the number of bits/time
unit and not distance/time unit.
Bluetooth - Bluetooth is an open standard for wireless
transmission of voice and data between mobile devices
(PCs, handheld computers, telephones and printers).
Bonjour - Also known as zero-configuration networking,
Bonjour enables the automatic discovery of computers,
devices, and services on IP networks. Bonjour allows
devices to automatically discover each other without the
need to enter IP addresses or configure DNS servers.
Bonjour is developed by Apple Computer Inc.
BOOTP (Bootstrap Protocol) - A protocol that can
automatically configure a network device (give it an IP
address). BOOTP is the basis for a more advanced network
management protocol, the Dynamic Host Configuration
Protocol (DHCP).
Broadband - In network engineering terms, this describes
transmission methods where two or more signals share
the same carrier. In more popular terminology, broadband
is taken to mean high-speed data transmission.