A video server is a computer-based device that is dedicated to delivering video. Video servers are used in a number of applications, and often have additional functions and capabilities that address the needs of particular applications. For example, video servers used in security, surveillance and inspection applications typically are designed to capture video from one or more cameras and deliver the video via a computer network. In video production and broadcast applications, a video server may have the ability to record and play recorded video, and to deliver many video streams simultaneously. Video broadcast and production In TV broadcast industries, a server is a device used to store broadcast quality images and allows several users to edit stories using the images they contain simultaneously. The video server can be used in a number of contexts, some of which include: News: providing short news video clips as part of a news broadcast as seen on networks (like CNN and Fox News). Production: enhance live events with instant replays and slow motion and highlights (sport production) (see OB Vans) Instruction: delivering course material in video format. Public Access: delivering city specific information to residents over a cable system. Surveillance: deliver real-time video images of protected site. Entertainment: deliver anything used for entertainment. It can be gaming, news, movie trailers, or movies. A professional-grade video server performs recording, storage, and playout of multiple video streams without any degradation of the video signal. Broadcast quality video servers often store hundreds of hours of compressed audio and video (in different codecs), play out multiple and synchronised simultaneous streams of video by, and offer quality interfaces such as SDI for digital video and XLR for balanced analog audio, AES/EBU digital audio and also Time Code. A genlock input is usually provided to provide a means of synchronizing with the house reference clock, thereby avoiding the need for timebase correction or frame synchronizers. Video servers usually offer some type of control interface allowing them to be driven by broadcast automation systems that incorporate sophisticated broadcast programming applications. Popular protocols include VDCP and the 9-Pin Protocol. They can optionally allow direct to disk recording using the same codec that is used in various post-production video editing software packages to prevent any wasted time in transcoding. Features Typically, a video server can do the following: Ingest of different sources : video cameras (multiple angles), satellite data feeds, disk drives