RP-NDI-TELETEXT_2021_09

proposal for carriage of  Teletext information in NDI metadata  DRAFT TBC

This page contains a technical proposal which is not currently a published or formal standard. If you have comments or feedback on the content of this proposal PLEASE contact us with your contribution.

 

This proposal defines a standardised wrapper to carry decoded Teletext subtitles  real time metadata over NDI by way of a recommended practice technical note.

 

Basic Premise:

This recommended practice provides a mechanism for an MPEGTS decoder to extract Teletext data from a stream and pass this onto an NDI system to action the message.

 

In this proposal, the  Teletext Data  is carried in a Teletext stream within an MPEG Transport Stream.  It translates into the real time (non frame based) NDI Metadata stream, with message data enclosed as <TELETEXT>

 

Note this is different to the DVB Bitmap subtitles which are covered in a differnt recommended practice document

 

Sent Messages are wrapped in the outer XML tag <TELETEXT>

 

NDIlib_metadata_frame_t meta_data

meta_data.p_data =

<TELETEXT>......</TELETEXT>

 

 

Example

TBC

 

 

 

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