Axis Communications 243SA user manual VOP- See VOP, Megapixel See Pixel

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78AXIS 243SA - Glossary

1 frame. Interlacing was developed many years ago for the analog TV world and is still used widely today. It provides good results when viewing motion in standard TV pictures, although there is always some degree of distortion in the image.

To view interlaced video on e.g. a computer monitor, the video must first be de-interlaced, to produce progressive video, which consists of complete images, one after the other, at 25 frames per second. See also Progressive scan.

IP (Internet Protocol) - The Internet Protocol is a method transmitting data over a network. Data to be sent is divided into individual and completely independent "packets." Each computer (or host) on the Internet has at least one address that uniquely identifies it from all others, and each data packet contains both the sender's address and the receiver's address.

The Internet Protocol ensures that the data packets all arrive at the intended address. As IP is a connectionless protocol, which means that there is no established connection between the communication end-points, packets can be sent via different routes and do not need to arrive at the destination in the correct order.

Once the data packets have arrived at the correct destination, another protocol - Transmission Control Protocol (TCP) - puts them in the right order.

See also TCP.

IP address - An IP address is simply an address on an IP network used by a computer/device connected to that network. IP addresses allow all the connected computers/devices to find each other and to pass data back and forth.

To avoid conflicts, each IP address on any given network must be unique. An IP address can be assigned as fixed, so that it does not change, or it can be assigned dynamically (and automatically) by DHCP.

An IP address consists of four groups (or quads) of decimal digits separated by periods, e.g. 130.5.5.25. Different parts of the address represent different things. Some part will represent the network number or address, and some other part will represent the local machine address. See also IP (Internet Protocol).

Inputs/Outputs (I/Os) - The digital I/Os on, for example, a network camera can be used to connect any device that can toggle between an open and a closed circuit.

For example, if a door switch is used as an input device, opening the door could trigger the upload of video images and the sending of notification messages.

An output might, for example, be used to automatically start a siren when there is a motion detection trigger.

I-VOP- See VOP.

JPEG (Joint Photographic Experts Group) - Together with the GIF file format, JPEG is an image file type

commonly used on the web. A JPEG image is a bitmap, and usually has the file suffix '.jpg' or ".jpeg." When creating a JPEG image, it is possible to configure the level of compression to use. As the lowest compression (i.e. the highest quality) results in the largest file, there is a trade-off between image quality and file size.

kbit/s (kilobits per second) - A measure of the bit rate, i.e. the rate at which bits are passing a given point. See also Bit rate.

LAN (Local Area Network) - A LAN is a group of computers and associated devices that typically share common resources within a limited geographical area.

Linux - Linux is an open source operating system within the UNIX family. Because of its robustness and availability, Linux has won popularity in the open source community and among commercial application developers.

Lux - A standard unit of illumination measurement.

MAC address (Media Access Control address) - A MAC address is a unique identifier associated with a piece of networking equipment, or more specifically, its interface with the network. For example, the network card in a computer has its own MAC address.

Manual iris - This is the opposite of an autoiris, i.e. the camera iris must be adjusted manually to regulate the amount of light allowed to reach the image sensor.

Mbit/s (Megabits per second) - A measure of the bit rate, i.e. the rate at which bits are passing a given point. Commonly used to give the "speed" of a network. A LAN might run at 10 or 100 Mbit/s. See also Bit rate.

Monitor - A monitor is very similar to a television set, but lacks the electronics to pick up regular television signals.

Motion JPEG - Motion JPEG is a simple compression/decompression technique for network video. Latency is low and image quality is guaranteed, regardless of movement or complexity of the image. Image quality is controlled by adjusting the compression level, which in turn provides control over the file size, and thereby the bit rate.

High-quality individual images from the Motion JPEG stream are easily extracted. See also JPEG and GIF.

Megapixel - See Pixel.

MPEG (Moving Picture Experts Group) - The Moving Picture Experts Group develops standards for digital video and audio compression. It operates under the auspices of the International Organization for Standardization (ISO). The MPEG standards are an evolving series, each designed for a different purpose.

MPEG-2- The designation for a group of audio and video coding standards, and is typically used to encode audio and video for broadcast signals, including digital satellite and Cable TV. MPEG-2, with some modifications, is also

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Contents Axis 243SA Video Server User’s Manual About This Document Page Contents Axis 243SA Video Server Glossary Index Product description Front panelLED indicators Switches & connectorsRear panel Axis 243SA Product descriptionAxis 243SA Product description Using Axis 243SA Accessinccg the video serverLive View AMC Audio controls Video and audio streams Video stream typesMotion Jpeg How to stream MPEG-4 MPEG-4 protocols and communication methodsAxis Media Control AMC Other methods of accessing the video stream RTP/RTSP/HTTP or RTP/RTSP/HTTPSAccessing the audio streams Other MPEG-4 clientsConfiguring the video server Accessing the Setup toolsText Overlay Settings Video & image settingsImage settings Image AppearanceVideo Stream Video source settingsAdvanced MPEG-4 settings TestOverlay/Mask type Advanced Mjpeg settingsOverlay/Mask settings Upload and use an overlay imageOverlay image requirements Overlay image limitationsImage Formats Image Size Axis 243SA Video & image settings Audio Audio settingsEnable Audio Audio ChannelsAudio Input Advanced Audio Settings Noise canceller attenuationAudio Output Axis 243SA Audio Live View Config Customizing the defaultLayout User-defined Links Upload Own Web FilesOwn Home Check Show custom linkHtml Examples External Video Example of a path to an external video sourceEvent type Event configurationEvent servers Server type PurposeTriggered Event How to set up a triggered eventEvent types Click Add triggered in the Event typesScheduled event How to set up a scheduled eventPre-trigger and post-trigger buffers Click Add scheduled on the Event typesCamera tampering Motion detectionHow to configure Motion Detection Port status Object SizeInstalling PTZ devices Pan Tilt ZoomPTZ configuration Preset positionsGuard Tour Advanced PTZ control queue Axis 243SA Pan Tilt Zoom PTZ controls Using CGI links to control PTZ devices PTZ control modesControl panel Axis 243SA Pan Tilt Zoom IP address filtering System optionsSecurity Viewer802.1x Network Admission Control Axis 243SA System optionsAxis 243SA System options Authentication process CA serversNetwork Basic TCP/IP settings IP Address ConfigurationDate & time Services NTP Configuration Network Advanced TCP/IP settingsDNS configuration Host name configurationNAT traversal Network trafficQoS Quality of service Smtp emailBonjour UPnPRTP Multicast/MPEG-4 Ports & devicesMaintenance Upgrade Server See Upgrading the firmware, onSystem Overview SupportSupport Overview Logs & ReportsAdvanced Resetting to the factory default settings Using the Control ButtonUnit connectors D-Sub connectorPin I/O terminal connector Pin Function DescriptionSchematic diagram I/O terminal connector COM ports RS-232 and RS-485To BNC cable Troubleshooting Checking the firmwareUpgrading the firmware Emergency recovery procedure Axis video server cannot be accessed from a web browser Alarms, etc, to a destination outside the local networkLit Snapshot images Video Image ProblemsNo images displayed in the Web interface Only I framesAudio Audio volume too low/highAudio Advanced Settings Poor audio qualityTechnical specifications ModelsConnectors Video access from WebVideo management General performance considerations Optimizing your systemFrame rates Motion Jpeg Frame rates MPEG-4Bandwidth Axis 243SA Technical specifications Active Speaker a speaker with a built-in power amplifier GlossaryCompression See Image Compression De-interlacing See InterlacingFixed iris See Autoiris Half-duplex See Full-duplexVOP- See VOP Megapixel See PixelAxis 243SA Glossary Axis 243SA Glossary SSL/TSL An I-VOP is a complete image frame Index Http API requests Http port number 52 Http serverUDP Viewer settings To BNC cable Axis 243SA Index