Glossary154GlossaryOverview of specialist terms1080iHDTV image signal with 1080 pixels and interlaced dis-play.16:9Cinematographic aspect ratio on widescreen displays.720pHDTV image signal with 1280 x 720 pixels and progres-sive display.CIFCommon Intermediate FormatOriginally planned for converting PAL to the NTSC stan-dard. CIF corresponds to a video resolution of 352 x 288pixels (2CIF = 704 x 288 pixels; 4CIF = 704 x 576 pixels).CINCHSocket type used for analogue audio or CVBS video sig-nals.CVBSColour, Video, Blank and Sync – The simplest variationof video signals (also known as composite video). Theimage quality is comparatively low.DDNSDynamic Domain Name System entryNetwork service which provides and updates IP ad-dresses of its clients in a database.DHCPDynamic Host Configuration ProtocolNetwork protocol which allows the automatic connectionof devices (clients) in existing networks. DHCP servers(e.g. Internet routers) automatically assign the IP ad-dress, network mask, gateway, DNS server and WINSserver (when required). Only the automatic acquisition ofIP addresses must be activated for the client in this case.DomainName used for the identification of websites on the Inter-net (e.g. www.abus-sc.de).Dual StreamDual stream is a video transmission method. A high-resolution recording and lower-resolution transmissionare made over the network, for example. The mainstream has a 4CIF resolution and the sub-stream has aCIF resolution.DVRDigital Video Recorder – A device used for recording dif-ferent video and audio sources (analogue, digital). Thedata is compressed for recording and saved on hard diskdrives (HDD).H.264(MPEG-4 AVC) – Standard method for the highly-efficientcompression of video signals. Used on Blu-ray discs orvideo conference systems, for example.HDDHard Disk DriveDigital data storage on computers or DVRs.GIGABYTEUnit of capacity for storage media (HDD, USB, SD/MMCcards).HDVRHybrid DVR – DVR used for recording analogue camerasand network cameras.httpHypertext Transfer ProtocolMethod for transmitting data across networks. Primarilyused for displaying websites in a browser.INTERLACEDMethod for improving the picture quality of a video signalwithout consuming extra bandwidth (scan pattern onevery second line).IP addressAn address in the computer network based on the Inter-net protocol. Allows different devices to identify them-selves in a network so that they are accessed specifi-cally.JPEGCompression method for photo images with minimal loss.Most digital cameras save photos in JPEG format.