Video server

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Front and back views of a small IP video server with audio and composite video inputs (Sensoray 2453S) 2453 IP video server.jpg
Front and back views of a small IP video server with audio and composite video inputs (Sensoray 2453S)

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.

Contents

Video broadcast and production

A video replay server, commonly used to provide instant replay in broadcasts of sporting events (EVS XT2) XT2 SERVER.jpg
A video replay server, commonly used to provide instant replay in broadcasts of sporting events (EVS XT2)
Large online providers of video on-demand employ clusters of servers such as this to simultaneously output multiple streams (Emulab) Emulab-cluster2-back.jpg
Large online providers of video on-demand employ clusters of servers such as this to simultaneously output multiple streams (Emulab)

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.

Features

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.

Video surveillance and inspection

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]

See also

Related Research Articles

The Session Initiation Protocol (SIP) is a signaling protocol used for initiating, maintaining, and terminating real-time sessions that include voice, video and messaging applications. SIP is used for signaling and controlling multimedia communication sessions in applications of Internet telephony for voice and video calls, in private IP telephone systems, in instant messaging over Internet Protocol (IP) networks as well as mobile phone calling over LTE (VoLTE).

Video Electronic moving image

Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media. Video was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) systems which, in turn, were replaced by flat panel displays of several types.

Voice over Internet Protocol (VoIP), also called IP telephony, is a method and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. The terms Internet telephony, broadband telephony, and broadband phone service specifically refer to the provisioning of communications services over the Internet, rather than via the public switched telephone network (PSTN), also known as plain old telephone service (POTS).

Universal Plug and Play (UPnP) is a set of networking protocols 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.

VoIP phone Phone using one or more VoIP 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 Real-time video communication

Videotelephony, also known as videoconferencing and video teleconferencing, is the two-way or multipoint reception and transmission of audio and video signals by people in different locations for real time communication. A videophone is a telephone with a video camera and video display, capable of simultaneous video and audio communication. Videoconferencing implies the use of this technology for a group or organizational meeting rather than for individuals, in a videoconference. Telepresence may refer either to a high-quality videotelephony system or to meetup technology, which can go beyond video into robotics. Videoconferencing has also been called "visual collaboration" and is a type of groupware.

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.

IP camera Digital video camera connected to the Internet

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, usually used for surveillance.

Central apparatus room Room where shared broadcast equipment is located

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

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.

Tieline Technology has offices in Indianapolis in the United States and in Perth, Western Australia. The company has a wide and established distribution network throughout Europe, the Americas and Australasia. Tieline develops a range of broadcast audio codecs that are sold to television and radio networks around the globe. All Tieline codecs are IP codecs, ISDN codecs, POTS codecs, GSM codecs, X.21 codecs and satellite-capable codecs.

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.

WebRTC is a free and open-source project providing web browsers and mobile applications with real-time communication (RTC) via application programming interfaces (APIs). It allows audio and video communication to work inside web pages by allowing direct peer-to-peer communication, eliminating the need to install plugins or download native apps. Supported by Apple, Google, Microsoft, Mozilla, and Opera, WebRTC specifications have been published by the World Wide Web Consortium (W3C) and the Internet Engineering Task Force (IETF).

An online video platform (OVP), provided by a video hosting service, enables users to upload, convert, store and play back video content on the Internet, often via a structured, large-scale system that may generate revenue. Users generally will upload video content via the hosting service's website, mobile or desktop application, or other interfaces (API). An example of an OVP is YouTube. The type of video content uploaded might be anything from shorts to full-length TV shows and movies. The video host stores the video on its server and offers users the ability to enable different types of embed codes or links that allow others to view the video content. The website, mainly used as the video hosting website, is usually called the video-sharing website.

Network Device Interface (NDI) is a royalty-free software specification developed by NewTek to enable video-compatible products to communicate, deliver, and receive high-definition video over a computer network in a high-quality, low-latency manner that is frame accurate and suitable for switching in a live production environment.

Channel in a box is the name given to an all-in-one playout device for broadcast television. Commonly based on a standard PC, it includes the ability to store content immediately required, add graphics, and deliver it to a transmission chain. Thus it provides an integrated, software playout platform.

References

  1. Viewing Your Security Camera on Your Android Smartphone with MPRMS