Axis Communications 241SA ユーザーズマニュアル

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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.