Axis Communications 211M user manual Glossary of Terms

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AXIS 211M - Glossary of Terms

Glossary of Terms

802.1x - An IEEE standard for port-based Network Admission Control. It provides authentication to devices attached to a network port (wired or wireless), establishing a point-to-point connection, or, if authentication fails, preventing access on that port. 802.1x is based on EAP (Extensible Authentication Protocol).

ActiveX - 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.

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.

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) - This chip is used for image compression.

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 (or 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.

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." GIF's and JPEG's 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 devices to automatically discover each other on a network, without having to enter IP addresses or configure DNS servers. Bonjour is a trademark of Apple Computer, Inc.

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.

CCD (Charged Coupled Device) - This light-sensitive image device used in many digital cameras is a large integrated circuit that contains hundreds of thousands of photo-sites (pixels) that convert light energy into electronic signals. Its size is measured diagonally and can be 1/4", 1/3", 1/2" or 2/3".

CGI (Common Gateway Interface) - A specification for communication between a web server and other (CGI) programs. For example, a HTML page that contains a form might use a CGI program to process the form data once it is submitted.

CIF (Common Intermediate Format) - CIF refers to the analog video resolutions 352x288 pixels (PAL) and 352x240 pixels (NTSC). See also Resolution.

Client/Server - Client/server describes the relationship between two computer programs in which one program, the client, makes a service request from another program, the server, which fulfils the request. Typically, multiple client programs share the services of a common server program. A web browser is a client program that requests services (the sending of web pages or files) from a web server.

CMOS (Complementary Metal Oxide Semiconductor) - A CMOS is a widely used type of semiconductor that uses both negative and positive circuits. Since only one of the circuit types is on at any given time, CMOS chips require less power than chips using just one type of transistor. CMOS image sensors also allow processing circuits to be included on the same chip, an advantage not possible with CCD sensors, which are also much more expensive to produce.

Codec - In communications engineering, a codec is usually a coder/decoder. Codecs are used in integrated circuits or chips that convert, e.g. analog video and audio signals into a digital format for transmission. The codec also converts received digital signals back into analog format. A codec uses analog-to-digital conversion and digital-to-analog conversion in the same chip.

Codec can also mean compression/decompression, in which case it is generally taken to mean an algorithm or computer program for reducing the size of large files and programs.

Compression - See Image Compression.

Contrast - Defines the degree of difference between the lightest and darkest parts of an image or video stream.

DC-Iris - This special type of iris is electrically controlled by the camera, to automatically regulate the amount of light allowed to enter.

DHCP (Dynamic Host Configuration Protocol) - DHCP is a protocol that lets network administrators automate and centrally manage the assignment of Internet Protocol (IP) addresses to network devices in a network.

DHCP uses the concept of a "lease" or amount of time that a given IP address will be valid for a computer. The lease time can vary, depending on how long a user is likely to require the network connection at a particular location.

DHCP also supports static addresses for, e.g. computers running web servers, which need a permanent IP address.

DNS (Domain Name System) - DNS is used to locate and translate Internet domain names into IP (Internet Protocol) addresses. A domain name is a meaningful and easy-to-remember name for an Internet address. For example the domain name www.example.com is much easier to remember than 192.0.34.166. The translation tables for domain names are contained in Domain name servers.

Domain Server - Domains can also be used by organizations who wish to centralize the management of their (Windows) computers. Each user within a domain has an account that usually allows them to log in to and use any computer in the domain, although restrictions may also apply. The domain server is the server that authenticates the users on the network.

Duplex - See Full-duplex.

Ethernet - Ethernet is the most widely installed local area network technology. An Ethernet LAN typically uses special grades of twisted pair wires. The most commonly installed Ethernet systems are 10BASE-T and 100BASE-T10, which provide transmission speeds up to 10 Mbps and 100 Mbps respectively.

ETRAX (Ethernet Token Ring AXIS) - Axis' own microprocessor.

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Contents Axis 211M About this Document Axis 211M Table of contents Axis 211M Table of contents Product Features Key featuresOverview Status indicator & MicrophoneTerminal connector DC-Iris control cableLED Accessing the Axis 211M from the Internet Using the Network CameraSet the password Accessing the Axis 211MLive View AMC audio controls How to stream MPEG-4 Video StreamMotion Jpeg Alternative methods of accessing the video streamMPEG-4 clients Axis Media Control AMCConfiguration Accessing the Setup toolsAxis Media Control Image Appearance Video and Image settingsText Overlay Settings Video StreamOverlay/Mask Type Overlay/Mask SettingsAdvanced Camera Settings Overlay image requirementsAdvanced MPEG-4 Settings GOV SettingsBit Rate Control Audio Channels Audio mode Audio SettingsEnable Audio Audio InputAudio Output Advanced AudioLive View Config Customize the defaultUpload Own Web Files User Defined Links Default Video FormatOwn home Example Check Show Custom LinkHtml Examples Sequence ModeDefault Viewer External VideoEvent Servers Event ConfigurationConfiguring Event Types DefinitionsTriggered Event Audio alarmHow to set up a triggered event Click Add triggered on the Event typesConfiguration example Click Add scheduled on the Event types Motion DetectionPort Status Object SizeSystem Options SecurityIP Address Filtering Authentication process Date & Time802.1X Network Admission Control IP Address Configuration Network Basic TCP/IP SettingsNetwork Advanced TCP/IP Settings ServicesLink-Local IPv4 Address NTP ConfigurationHost Name Configuration NAT traversal port mappingQoS Quality of Service Network TrafficUPnP LED SettingsSmtp email BonjourSupport MaintenanceConfiguration InformationResetting to the Factory Default Settings Using the Reset ButtonAdvanced Terminal Connector Connection diagramFunction Pin number Specifications Checking the Firmware TroubleshootingEmergency Recovery Procedure Upgrading the FirmwareSymptoms, Possible Causes and Remedial Actions Axis SupportVideo/Image problems general Video/image problems MPEG-4Decode only I frame Problems uploading files Poor quality snapshot imagesBrowser freezes Technical Specifications IlluminationMaintenance Video access from Video managementGeneral performance considerations Optimizing your systemGlossary of Terms Etrax Ethernet Token Ring Axis Axis own microprocessorVOP See VOP Axis 211M Glossary of Terms SSL/TLS Secure Socket Layer/Transport Layer Security URL Uniform Resource Locator An address on the networkAxis 211M Glossary of Terms Axis 211M Index Snmp