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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.
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:
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.
Typically, a video server can do the following:
Generally, they have several bi directional channels (record and ingest) for video and audio. A perfect synchronisation is necessary between those channels to manage the feeds.
In some surveillance and inspection applications, IP video servers are employed which convert analog video signals into IP video streams. These IP video servers can stream digitized video over IP networks in the same way that an IP camera can. Because an IP Video server uses IP protocols, it can stream video over any IP-compatible network, including via a modem for access over a phone or ISDN connection. With the use of a video server attached to an analog camera, the video from an existing surveillance system can be converted and networked into a new IP surveillance system.
In the video security industry a video server is a device to which one or more video sources can be attached. Video servers are used to give existing analog systems network connectivity. Video servers are essentially transmission/ telemetry / monitoring devices. Viewing is done using a web browser or in some cases supplied software. These products also allow the upload of images to the internet or direct viewing from the internet. In order to upload to the internet an account with an ISP (internet service provider) may be required.
Phone apps that send direct security video feed to smartphones from security video servers are another recent security video server application innovation. This allows smartphone users to view security video server feed from anywhere they can use their smartphone. [1]
The Session Initiation Protocol (SIP) is a signaling protocol used for initiating, maintaining, and terminating communication sessions that include voice, video and messaging applications. SIP is used in Internet telephony, in private IP telephone systems, as well as mobile phone calling over LTE (VoLTE).
Voice over Internet Protocol (VoIP), also called IP telephony, is a method and group of technologies for voice calls for the delivery of voice communication sessions over Internet Protocol (IP) networks, such as the Internet.
Universal Plug and Play (UPnP) is a set of networking protocols on the Internet Protocol (IP) that permits networked devices, such as personal computers, printers, Internet gateways, Wi-Fi access points and mobile devices, to seamlessly discover each other's presence on the network and establish functional network services. UPnP is intended primarily for residential networks without enterprise-class devices.
Conexant Systems, Inc. was an American-based software developer and fabless semiconductor company that developed technology for voice and audio processing, imaging and modems. The company began as a division of Rockwell International, before being spun off as a public company. Conexant itself then spun off several business units, creating independent public companies which included Skyworks Solutions and Mindspeed Technologies.
A VoIP phone or IP phone uses voice over IP technologies for placing and transmitting telephone calls over an IP network, such as the Internet. This is in contrast to a standard phone which uses the traditional public switched telephone network (PSTN).
Videotelephony is the use of audio and video for real-time communication between people.
A video reference monitor, also called a broadcast reference monitor or just reference monitor, is a specialized display device similar to a television set, used to monitor the output of a video-generating device, such as playout from a video server, IRD, video camera, VCR, or DVD player. It may or may not have professional audio monitoring capability. Unlike a television set, a video monitor has no tuner and, as such, is unable independently to tune into an over-the-air broadcast like a television receiver. One common use of video monitors is in television stations, television studios, production trucks and in outside broadcast vehicles, where broadcast engineers use them for confidence checking of analog signal and digital signals throughout the system. They can also be used for color grading if calibrated, during post-production. Banks of reference monitors are also a common sight on the sets of newscasts, showing internal or external feeds.
Axis Communications AB is a Swedish manufacturer of network cameras, access control, and network audio devices for the physical security and video surveillance industries. Since 2015, it operates as an independent subsidiary of Canon Inc.
Asynchronous Serial Interface, or ASI, is a method of carrying an MPEG Transport Stream (MPEG-TS) over 75-ohm copper coaxial cable or optical fiber. It is popular in the television industry as a means of transporting broadcast programs from the studio to the final transmission equipment before it reaches viewers sitting at home.
In broadcasting, channel playout is the generation of the source signal of a radio or television channel produced by a broadcaster, coupled with the transmission of this signal for primary distribution or direct-to-audience distribution via any network. Such radio or television distribution networks include terrestrial broadcasting, cable networks, satellites, IPTV, OTT Video, point-to-point transport over managed networks or the public Internet, etc.
A media server is a computer appliance or an application software that stores digital media and makes it available over a network.
An Internet Protocol camera, or IP camera, is a type of digital video camera that receives control data and sends image data via an IP network. They are commonly used for surveillance, but, unlike analog closed-circuit television (CCTV) cameras, they require no local recording device, only a local area network. Most IP cameras are webcams, but the term IP camera or netcam usually applies only to those that can be directly accessed over a network connection.
In broadcast facilities and television studios, a central apparatus room, central machine room, or central equipment room (CER), or central technical area (CTA), or rack room is where shared equipment common to all technical areas is located. Some broadcast facilities have several of these rooms. It should be air-conditioned, however low-noise specifications such as acoustical treatments are optional. Equipment is connected either directly with an attached foldout monitor, keyboard and mouse or remotely via KVM switch, SSH, VNC, RS-232 or remote desktop.
Video Share is an IP Multimedia System (IMS) enabled service for mobile networks that allows users engaged in a circuit switch voice call to add a unidirectional video streaming session over the packet network during the voice call. Any of the parties on the voice call can initiate a video streaming session. There can be multiple video streaming sessions during a voice call, and each of these streaming sessions can be initiated by any of the parties on the voice call. The video source can either be the camera on the phone or a pre-recorded video clip.
Audio connectors and video connectors are electrical or optical connectors for carrying audio or video signals. Audio interfaces or video interfaces define physical parameters and interpretation of signals. For digital audio and digital video, this can be thought of as defining the physical layer, data link layer, and most or all of the application layer. For analog audio and analog video these functions are all represented in a single signal specification like NTSC or the direct speaker-driving signal of analog audio.
The RVU protocol is an Application Layer protocol, that combines the pre-existing Digital Living Network Alliance (DLNA) standards and a new Remote User Interface (RUI) protocol, which works similar to Remote Desktop Protocol (RDP). The RVU RUI protocol is intended to allow an RVU-enabled client, such as a TV, to receive a pixel-accurate display of the user interface available on an RVU server.
The Helix Universal Media Server was a product developed by RealNetworks and originates from the first streaming media server originally developed by Progressive Networks in 1994. It supported a variety of streaming media delivery transports including MPEG-DASH RTMP (flash), RTSP (standard), HTTP Live Streaming (HLS), Microsoft Silverlight and HTTP Progressive Download enabling mobile phone OS and PC OS media client delivery.
An online video platform (OVP) enables users to upload, convert, store, and play back video content on the Internet, often via a private server structured, large-scale system that may generate revenue. Users will generally upload video content via the hosting service's website, mobile or desktop application, or other interfaces (API), and typically provides embed codes or links that allow others to view the video content.
Network Device Interface (NDI) is a software specification developed by the technology company NewTek that enables high-definition video to be delivered, received, and communicated over a computer network in a low-latency, high-quality manner. The specification is royalty-free and allows for frame accurate switching, making it suitable for use in live production environments.