Main Page/Cloud Browser TF/UseCases/Tuner

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Tuners

UC-1: application need to tune to a broadcast channel

Description

As an application i would like to tune to a broadcast channel so-that i could leverage the tuner on client
  1. The cloud browser receives tuning information from a backend system
  2. The cloud browser maps this information to the tv control api
  3. The application uses the tv control api to tune to a channel
  4. the cloud browser signals the client to tune using the tuner
  5. tuner will tune to the appropriate broadcast channel.
The backend system in this case is vendor specific. A vendor could choose to use a web service with all the appropriate information, send the information from the client, etc. As an example the w3c tv control api is used (if there are other means in the future this could be used as-well). The application could be an html authored epg. The real different with a local browser is the tune command to the client. i.e. a local browser will communicate directly to the tuner where the rte needs a general solution to tune to a specific out-of-band media. This is particular the case with a multicast infrastructure where a cloud browser implementer doesn't want to receive all the multicast traffic.

Actors

  • client
  • application
  • tuner
  • backend system
  • cloud browser

Notes

A tuner is part of an integrated receiver/decoder (IRD) and is used to demodulate radio frequencies into (usually) a descrambled mpeg ts stream, which is via a Conditional Access System demuxed into video, audio and data containing others System Information (SI). The SI data could be used to generate epg data for instance. The latter is done within the middleware. A single tuner could have different sources. For example, it could handle a DVB-T stream and DVB-C.
Here is a schematic overview:

Tuner.png

that term “tune” is used to change from a particular frequency. Even in a IPTV we could use this term even there is no existing tuner. Tune or tuning in this context means a channel/video-source switch.
The tune command will be used in the double stream approach where the rte will leverage the tuner and tune to an particular channel.

requirements

Conforming specifications should provide a means to retrieve a tune signal and playback the signalled source
accessibility

No identified accessibility requirements at this time

dependencies

This use case depends on an api to express a tune command such as the TV control api

Authors

Colin Meerveld (talk)

History

26-1-2016 Colin Meerveld (talk) created