[FFmpeg-user] Export Subtitles live from HD-SDI

[florian.hesse at rbb-online.de]

Hello everyone,

i'm working on a project where we want to livestream one TV-Program with 
MPEG-DASH. There for we need seperate subtitles. The encoder gets the 
signal over HD-SDI wich supports embedded subtitles in Teletext with SMPTE 
2031.
Our capturecard will be a Blackmagic Decklink Duo wich supports VANC-Data. 


I know that ffmpeg can extract closed captions from files. But what about 
Livesignals like from SDI-Signals?
Thank you,
Florian