ActiveX
ActiveX is a software framework created by Microsoft developed for web browsers (primarily Internet Explorer) to facilitate rich media playback from a network or the Internet. Internet Explorer uses the ActiveX software framework to load other applications in the browser.
AF (Autofocus)
The ability of the camera to focus on and an object or specified area automatically.
Angle
The camera's field of view expressed in degrees, e.g. 30°. This refers to the angular range of the camera that you can focus on without distorting the image.
ARP (Address Resolution Protocol)
ARP is a protocol used for mapping an IP (Internet Protocol) address to a MAC address that is present in the local network.
ARTPEC (Axis Real Time Picture Encoder)
Is 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 custom designed circuit created for a particular use, rather than a general-purpose circuit.
Aspect ratio
Is the ratio of the width to the height of an image or monitor/screen. Common Aspect ratios are 4:3 and 16:9.
Autoiris (or DC-Iris)
An electrically controlled iris which can automatically controlling the amount of light that entering the camera’s sensor.
AVI (Audio Video Interleave)
Is a multimedia format that allows synchronous audio and video playback.
Bitmap
A bitmap is a digital image composed of a matrix of dots. Each dot corresponds to an individual pixel on a display. Each dot can be assigned a different color. These dots, when combined, can be used to represent any type of rectangular picture.
Bit rate
The bitrate, for video, is the number of bits that are processed within a unit of time (often shown as Kbps or Mbps).
Bluetooth
Bluetooth is an open wireless technology standard for transmitting voice and data between electronic devices over short distances.
Bonjour
Bonjour is a version of the Zeroconf (zero configuration) standard. It is used to automatically configure devices and discover services on an local network.
BOOTP (Bootstrap Protocol)
BOOTP is a computer networking protocol used to automatically configure devices on an IP network from a configuration server.
Broadband
In telecommunications, broadband describes data transmission which can transport multiple signals and traffic types on the same medium. Commonly it is used to describe any high-speed Internet access.
CCD (Charged Coupled Device)
A CCD (Charged Coupled Device) is the image sensor employed by most digital cameras. The CCD sensor is measured diagonally and can be 1/4", 1/3", 1/2" or 2/3".
CGI (Common Gateway Interface)
Is a standard protocol for web servers to execute programs running on a web server, which can generate website content dynamically.
CIF (Common Intermediate Format)
CIF (Common Intermediate Format or Common Interchange Format) is a format used to standardize the horizontal and vertical resolutions, in pixels, of video signals. CIF defines a video sequence with a resolution of 352 x 240 on NTSC and 352 × 288 on PAL.
Client/server
The Client/Server structure is the relationship between the client, a device or program that requests a resource or task, and the server, a device or program that shares the resource or fulfils the task. The server can fulfil requests from multiple clients.
CMOS (Complementary Metal Oxide Semiconductor)
A CMOS (Complementary Metal Oxide Semiconductor) image sensor is similar to a CCD image sensor but typically performs better in low light applications.
Coaxial cable
Coaxial cable is a type of cable that used to transmit the analog signal from a camera to a monitor or DVR.
Codec
A Codec is used to convert analog video and audio signals into a digital format and back to analog. The codec can be an application on a computer or an integrated circuit.
Composite video
A video signal that combines the red, green, and blue video channels with the synchronizing, blanking, and color burst signals into a single standard definition.
Compression
See Image Compression.
Contrast
Contrast is the different between the brightest and darkest portions of an image or video.
Control unit
In a multi camera CCTV system the Control unit directs the video signals the recorders and/or monitors. There are three basic types of Video Control Unit: Multiplexer, Switch and Quad.
DC-Iris
See Autoiris
Decoder
See video decoder.
De-interlacing
De-interlacing is the process of converting interlaced video into a video stream that can be displayed, such as an analog television signals or HDTV signals.
DHCP (Dynamic Host Configuration Protocol)
DHCP is a network management protocol used to dynamically assign an IP address to any device, or node, on a network. DHCP automates and centrally manages these configurations rather than requiring the IP addresses to be manually assign IP addresses to all the network devices.
DNS (Domain Name Servers)
DNS is used to convert fully qualified domain names in to IP (Internet Protocol) addresses. A domain name is an easily remembered address which can be significate to the organization.
Domain server
A Domain Server (or Domain Controller) is used by organizations to centralize the management of their network computers and devices. When a user account logs into the network it will be provided access to the resources defined on the Domain Server.
Duplex
See Full-duplex.
Encoder
See video encoder.
Ethernet
Ethernet is the standard way used to connect computers, and other devices, on a network over a wired connection. Common Ethernet speeds are 10Mbps and 100Mbps.
ETRAX (Ethernet Token Ring AXIS)
The ETRAX chip is the cornerstone of Axis technology and the 'brain' in nearly all Axis products. A multipurpose Linux chip with integrated Ethernet networking and extremely flexible I/O options.
Factory default settings
This refers to the original software state of the device as it was delivered from the factory. This feature will effectively erase all of the settings and other data from the device.
Firewall
A firewall is a dedicated device or software running on a computer that monitors and limits network traffic using predefined rules.
Fixed iris
A fixed Iris Is an Iris that cannot be adjusted for changing light levels of the environment. Cameras with a fixed iris can be used in indoor environments where the light levels are relatively constant.
Focal length
The distance, measured in millimeters, from the lens to the surface of the image sensor. The shorter the distance the wider the field view is, the longer the distance the narrower the view.
FTP (File Transfer Protocol)
A network protocol used to transfer files from one computer to another, or between devices connected to the network or the internet.
Frame
A frame is a single video image (525 scan lines).
Frame rate
The Frame rate refers to the number of video images that can be captured, displayed, or recorded in a second.
Full-duplex
Full-duplex data transmission means that data can be sending and received on a signal carrier at the same time.
Gain
Gain represents an increase in voltage or power, normally expressed in dB.
Gateway
The gateway is a computer or device that interfaces with another network that use different protocols.
GIF (Graphics Interchange Format)
GIF is an image file format that supports both animated and static images commonly used in webpages.
GOV (Group Of VOPs)
A GOV (Group of VOPs) is the basic unit of an H.264 video stream. The GOV will contain different types and numbers of VOPs (I-VOP’s, P-VOP’s, etc.) which is determined by the GOV length and GOV structure.
GOV length
The GOV length specifies the number of images, or VOPs, in the GOV structure.
GOV structure
The GOV structure describes the composition of an H.264 video stream, as regards the type of images (I-VOP’s or P-VOP’s) included in the stream, and their internal order.
Half-duplex
Half-duplex data transmission means that data cannot be sent and receive on a signal carrier at the same time. The transmission will alternate between sending and receiving data.
H.264
Also known as MPEG-4 AVC (Advanced Video Coding) it is one of the most commonly used recording formats for high definition video. It offers significantly greater compression while using less hard drive storage space than previous formats.
Half-duplex
Half-duplex data transmission means that data cannot be sent and received on a signal carrier at the same time. Half-duplex alternates the direction of traffic between sending and receiving data
HDTV (High-definition television)
HDTV is a term used for a high-resolution standard that is capable of displaying on a wider screen (16:9 as opposed to 4:3).
HTML (Hypertext Markup Language)
Hypertext Markup Language is a standardized system for displaying text, graphics and hyperlinks on the internet. HTML tells the browser how to display the text and graphic on the visitor’s web browser.
HTTP (Hypertext Transfer Protocol)
HTTP (Hypertext Transfer Protocol) is the underlying protocol used on the internet, this protocol defines how messages are formatted and transmitted as well as how Web servers and browsers should interpret and respond to various commands.
HTTPS (Hypertext Transfer Protocol over SSL)
HTTPS (Hypertext Transfer Protocol over SSL) is part of HTTP with a connection encrypted by either SSL (Secure Socket Layer) or TLS (Transport Layer Security). The protocol is used for secure communication over the Internet to authenticate visited website and protect the privacy and integrity of the exchanged data.
Hub
A (network) hub, like a switch, is used to connect multiple devices to a network. The hub transmits all data to all devices connected to it, while a switch will only transmit the data to the device it is specifically intended for.
IEEE 802.11
IEEE 802.11 represents a group of media access control (MAC) and physical layer (PHY) specifications for the wireless local area network (WLAN) communication using the 900 MHz, 2.4, 3.6, 5, and 60 GHz frequency bands. This standard and it's amendments are the basis for wireless networks and products using the Wi-Fi brand.
Image compression
Image compression is the process of encoding or converting an image file so that it will consumes less disk space. Common file formats used for image compression are JPEG and GIF.
Interlacing
Interlacing is the process of changing a single video frame that consists of two sub-fields taken in sequence (an interlaced video).
IP (Internet Protocol)
Is a set of rules governing the format of data transmitted over the Internet or a Local Area Network (LAN).
IP address
The IP address (Internet Protocol address) is a numeric label assigned to each device that is connected to a computer network which uses the Internet Protocol for communication.
IP camera
An IP camera, or network camera, is a video camera that is connected to a network. The camera transmits the video over the network to an NVR or a connected device which may be on the LAN or the Internet.
Infrared (IR)
Infrared radiation is a portion of the electromagnetic spectrum that the naked human eye cannot see. An infrared camera is can detect the infrared energy emitted by heat sources and converts it into an image. IR cameras are effective in areas with little to no light. Adding an additional external infrared illuminator can increase the coverage area of the camera.
Inputs/Outputs (I/O’s)
Inputs/Outputs are devices that can trigger a predetermined action or become active after being signaled. Examples of I/O devices are motion sensors, loud speakers or door triggers.
ISMA (Internet Streaming Media Alliance)
ISMA has created a specification to facilitate interoperability between different clients and servers when transmitting MPEG-4 on a network.
JPEG (Joint Photographic Experts Group)
JPEG is a commonly used method of compression for digital images, usually has the file extension of .jpg or .jpeg.
Kbit/s or Kbps (kilobits per second)
See Bit rate.
LAN (Local Area Network)
A LAN (Local Area Network) is a group of computers and devices networked by a common resource, usually within the same office or building. LANs can typically allow connected computers to access and share data on the network as well as network devices (e.g. printers, scanners or copiers) also access to the Internet.
Lenses (or lens assembly)
A lens performs several functions. This includes defining the field of view and controlling the amount of light passing through to the image sensor.
Focusing within the lens assembly is done by adjusting either elements or the distance between the lens assembly and the image sensor.
Light sensitivity
See Minimum illumination.
Linux (GNU/Linux)
Linux is an open source operating system, designed to behave like Unix, used on computers, servers, mobile devices and IoT (Internet of Things) devices.
Lux
Lux is a standard unit of illumination measurement. Represented as lx, 1 lx is equal to one lumen per square meter.
MAC address (Media Access Control address)
A MAC address (Media Access Control address) of a device is a unique identifier assigned to the network interfaces (eg. a computer's network adapter).
Manual iris
A Manual iris is the opposite of the Auto=iris and must be manually adjusted to control the amount of light entering the camera's sensor.
Minimum illumination
Minimum illumination refers to the lowest light level that the camera needs to produce a usable image. The minimal illumination required to produce a usable image is dependent on how sensitive the camera is to light. Minimum illumination is measured in Lux (lx).
Monitor
A monitor is display like those used with a computer and some are similar to a television set but lacks a television tuner, the components used to pick up television broadcasts.
Motion JPEG
Motion JPEG (MJPEG) is a video compression format used to stream digital video images across a network or the Internet. The quality of the image is guaranteed, regardless of movement and the compression level can be adjusted for control of the image quality and the file size.
Megapixel
See Pixel.
MPEG (Moving Picture Experts Group)
MPEG (Moving Picture Experts Group) which develops standards for digital video and audio compression. It is part of the ISO (International Organization for Standardization) group. MPEG is also the name of a group of digital video compression standards and file formats. MPEG videos normally produce better quality video than the competing formats.
MPEG-2
MPAG-2 (a.k.a. H.222/H.262) which describes a combination of lossy video and audio data compression methods used in video broadcasts.
MPEG-4
MPEG-4 AVC (AKA H.264) is a video compression standard that offers significantly greater compression than its predecessors. MPEG-4 can support resolutions up to 4096×2304.
Multicast
Multicast is a method of group communication on a computer network where a data transmission is addressed to a group of destination computers simultaneously.
Multiplexer
A Multiplexer is a device that takes inputs from 2 or more video channels and combines them into one signal.
Network connectivity
Network Connectivity describes a connection, either wired or wireless, to a network of computers or devices. The connected network can be a LAN (Local Area Network) or the Internet.
NTSC (National Television System Committee)
NTSC is an analog color television standard used in North America and some of South America. NTSC defines a video signal using 525 TV lines per frame, at a refresh rate of 30 frames per second.
OEM (Original Equipment Manufacturer)
OEM refers to a company that produced components and equipment that may then be branded and sold by another manufacturer.
ONVIF (Open Network Video Interface Forum)
Is an organization which promotes the standardization of communication between and the compatibility of IP-based physical security products, regardless of the brand.
PAL (Phase Alternating Line)
PAL is an analog colour television display standard that is used primarily in Europe, China, Malaysia, Australia, New Zealand, the Middle East, parts of Africa, and other parts of the world. The PAL video signal uses 625 lines per frame and a frame rate of 25 frames per second.
PEM (Privacy Enhanced Mail)
PEM was a standard that provided for secure exchange of e-mail, which allow for confidentiality, sender authentication, and message integrity. PEM was never widely adopted and was replaced by PGP and S/MIME.
Ping
Ping is a basic network diagnostic tool that can verify the availability of the target host or device. When used the ping program sends a small packet of data to the specified target address and measures the amount of time it takes for the packet to be returned, this is measured in ‘ms’ (Milliseconds).
P-Iris
P-Iris is a type of automatic iris, this precise iris control was developed by Axis Communications of Sweden and Kowa Company of Japan. It involves a P-Iris lens and specialized software that will optimize image quality.
Pixel (Picture Element)
The Pixel is the smallest element of an image that is displayed in a monitor.
PoE (Power over Ethernet)
PoE is a technology that allows for a wired network device to receive power to operate over the Ethernet (network cable) used to transmit and receive data. This technology allows for devices to be placed in locations that have no available power outlets.
PPP (Point-to-Point Protocol)
PPP is a family of communication protocols used to establish a direct connection between two devices.
PPTP (Point-to-Point Tunnelling Protocol)
PPTP is a protocol that was used by corporations to extend their own corporate network through private tunnels over the public Internet.
Pre/post alarm images
Pre/post alarm images are images from immediately before and after an alarm is triggered. These images are stored in a buffer for later retrieval.
Privacy masking
Privacy masking allows selected areas of a scene to be blocked or masked from viewing and recording.
Progressive scan
Progressive scan, also referred to as non-interlaced scanning, scans or draws every image line by line in sequence.
Protocol
Protocol or communication protocols are rules in which computers communicate with each other.
Proxy server
A proxy server is a server (either a computer system or an application) that acts as an intermediary for requests from devices connected to the network seeking resources from other servers, either on the Local Area Network or the Internet.
P-VOP
See VOP.
Quad view
Quad view displays the images from four cameras then displays them on a single monitor.
QoS (Quality of Service)
QoS is a method to guarantee a minimal level of network traffic for a specified service or device.
Resolution
Image resolution is a measure of how much detail is in a digital image, as in the higher the resolution, the higher the level of detail in the image. Resolution are normally specified as the number of pixel columns (width) by the number of pixel-rows (height), e.g. 320x240. Alternatively, the total number of pixels (usually in megapixels) in the image can be used. In analog systems it is also common to use other format designations, as in CIF, QCIF, 4CIF, etc.
RS-232
RS-232 is a standard that describes the physical interface and protocol commonly used for low-speed serial data communication between devices.
RS-422
RS-422 is a serial interface standard which data is sent in a differential pair of wires which allows greater distances and higher data rates than non-differential serial standards.
RS-485
RS-485 is the upgraded version of RS-422 which supports up to 32 devices on the same connection.
RTP (Real-Time Transport Protocol)
The Real-time Transport Protocol (RTP) is a network protocol used to deliver audio and video streams over IP networks.
RTCP (Real-Time Control Protocol)
Related to RTP, RTCP provides out-of-band statistics and control information for an RTP session. It works with RTP in the delivery and packaging of multimedia data, but does not transport any media data itself.
RTSP (Real Time Streaming Protocol)
RTSP is a Network control protocol used in communications systems to control streaming media servers. This protocol is used to establish and control media being streamed during the session.
Router
A router is a networking device that directs data packets between computer networks.
Server
A server is a computer program that provides services to other computer programs. The computer that a server program runs in is frequently called a server. This computer may be a dedicated server or used for other purposes.
Sharpness
Sharpness refers to the find detail within an image.
Simplex
Simplex is a communications mode in which only one signal is transmitted in the same direction.
SMTP (Simple Mail Transfer Protocol)
SMTP is an Internet protocol used for email transmissions (sending and receiving). SMTP is also used to refer to the email client's/program's sending mail server setting.
SNMP (Simple Network Management Protocol)
SNMP is a protocol used to collect and organize information about managed devices within an IP network and for modifying that information to change device behavior.
Sockets
A socket is the endpoint of communications between processes on a computer network such as the Internet.
SSL/TLS (Secure Socket Layer/Transport Layer Security)
SSL/TLS (Secure Socket Layer/Transport Layer Security) are cryptographic protocols that provide communications security over a computer network.
Subnet & subnet mask
A subnet allows network traffic between hosts to be segregated based on a network configuration, by organizing hosts into logical groups. The subnet mask helps define the size of the segmented network.
Switch
A switch is a device that connects devices together on a network (either a LAN or WAN).
TCP (Transmission Control Protocol)
TCP is a suite of communication protocols used to interconnect network devices on a LAN or the Internet.
Telnet
Telnet is a simple and unsecure method with which to access another network device using a command line interface.
TVL (TV Lines)
TVL is best defined as an analog camera's or monitor's horizontal resolution.
UDP (User Datagram Protocol)
UDP is a different communications protocol to TCP (Transmission Control Protocol) that is primarily used to establish low-latency and loss tolerate connections between applications on the Internet.
Unicast
Unicast refers to one-to-one communication from one point in the network to another point, opposite from Multicast.
UPnP
UPnP is a standard that allows networked devices to automatically detect other connected devices.
URL (Uniform Resource Locator)
A URL is a address on the Internet.
USB (Universal Serial Bus)
USB is a cross-platform technology used to connect peripheral devices to a computer.
VAPIX®
VAPIX® is Axis’ own open application programming interface (API) for cost-efficient, flexible, scalable and future-proof integration with other systems.
Varifocal lens
A varifocal lens is a camera lens that has a variable focal length.
Video encoder
Video encoders, also referred to as video servers, enable an existing analog CCTV video surveillance system to be integrated with a network video system.
VPN (Virtual Private Network)
A VPN is used to create a secure link between the devices on a LAN or the Internet.
VOP (Video Object Plane)
A VOP is an image frame in an MPEG-4 video stream. There are several types of VOP:
- An I-VOP is a complete image frame.
- A P-VOP codes the differences between images, as long as it is more efficient to do so.
Otherwise it codes the whole image, which may also be a completely new image.
WAN (Wide-Area-Network)
A WAN consists or 2 or more LANs that can span a larger geographic area.
W-LAN (Wireless LAN)
A W-LAN is a LAN (Local Area Network) where the networked devices are connected wirelessly.
Web server
A Webserver is a server program that is designed to display webpages. Also see Server.
WEP (Wired Equivalent Privacy)
WEP is a security algorithm use for wireless networks or W-LANs.
WINS (Windows Internet Naming Service)
WINS is a system that determines the IP address associated with a particular network computer.
WPA-PSK (Wi-Fi Protected Access - Pre-Shared Key)
WINS is a wireless encryption method which uses a pre-shared key (PSK) for key management. WPA-PSK is a more secure system than WEP.
Zoom lens
A Zoom lens allows a camera to change the focal length. This provides the camera with the ability to magnify on to an object or area.
lundi, octobre 16, 2017