Playout
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In broadcasting, channel playout is the generation of the source signal of a radio or television channel produced by a broadcaster,
The television channel playout happens in master control room (MCR) in a playout area, which can be either situated in the central apparatus room or in purposely built playout centres, which can be owned by a broadcaster[2] or run by an independent specialist company that has been contracted to handle the playout for a number of channels from different broadcasters.
Some of the larger playout centres in Europe, Southeast Asia and the United States handle well in excess of 50 radio and television "feeds". Feeds will often consist of several different versions of a core service, often different language versions or with separately scheduled content, such as local opt outs for news or promotions.
Playout systems
Most broadcast automation systems will have a series of common device drivers built in, for example Sony VTR control (aka Sony Serial), Louth
This is the "traditional" method of playout automation, where there are multiple devices. Some modern automation systems use a unified playout method, where the broadcast server fulfills the functions of multiple devices as a self-contained system, like the PlayBox Technology channel-in-a-box.
Playout devices
Playout will usually involve an
The devices in the chain depend on the service required under the contract with the Channel. Typically a standard television channel would require a Master Control,
Other devices include:
Graphics inserters – At least one Graphics inserter, or one with several layers. This allows for
Subtitling inserters – This can be either closed or open – i.e. in vision as a graphic for all to see, or closed either as an
Audio servers – An audio playout system would provide scheduled voiceovers
Aspect Ratio Converters – These alter the picture shape or send an embedded signal to allow the material format to be displayed correctly on a particular feed (e.g. Widescreen on a standard non-widescreen Analogue terrestrial feed)
Some of these more advanced devices require information from the playlist, and so do not tend to use an RS422/232 driver, but a complex XML based system which allows for more complex metadata to be passed, e.g. a "Now" or "Next" Graphic can be created from a template using text information from the playlist.
Channel-in-a-box concept
With the "softwarization" of the various functions required to generate the channel signal in a playout system, the possibility to gather all of them into a single piece of equipment became possible. Such all-in-one video playout servers are known as channel-in-a-box systems.[3]
Playout Centers
Playout is one of the basic infrastructure of a playout center. Mostly called as channel in a box server, but basically composed of playout servers with integrated graphics and IP or ASI output. Aim of playout centers is mostly to serve customers a simple file based television facility. Up-link and TV Channel in a box servers simply provide the facility.
Scheduling
The playout system execute a scheduled and time-accurate playlist of content to generate a linear radio or television signal (or "feed"). Within that playlist, there is the content that goes "on-air": live or recorded shows/programs, ad breaks, auto-promo clips, etc.
Workflow
A common workflow is for the broadcast automation system to have a recording schedule to ingest material from a satellite or line feed source and then time-shift that material based on a playlist or schedule.
The playout schedule will have been created in the customer's broadcast programming scheduling system and exported into a format suitable to be used in the Playout system. There is a move to SMPTE-22, known as Broadcast Exchange Format (BXF) to try to standardise the messaging involved in this interaction.
The resulting playlist is "loaded" into the appropriate channel of the broadcast automation system in advance of the transmission time. Various processes will take place to ensure the content is available on the correct servers for playout at the right time, typically this involves advance requests to move material from deep storage such as Tape Archives or FTP Clusters to Broadcast Video servers, often using FTP.
On playing out the material, the audio and video signals are usually transported from the playout area to the network via a
Playout is often referred to as Presentation or Transmission (TX), and is under control of an automatic transmission system.
See also
- Broadcast
References
- ^ Pennington2008-01-28T18:10:01+00:00, Adrian. "Production: Why TV is playing away". Broadcast. Retrieved 2020-02-05.
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: CS1 maint: numeric names: authors list (link) - ^ TVTechnology (August 2004). "BBC Broadcast's Broadcast Centre". TvTechnology. Retrieved 2020-02-05.
- ^ DTVE Reporter (16 October 2012). "Optional extras: channel playout choices and localisation". DigitalTV Europe.