How can I keep the display of embedded live CEA-608 captions centered (vs left justified) in a YouTube stream target?

Wowza Streaming Engine
1

Issue: In youtube, most of the live captions are centered at the bottom of the player, but some are left justified. It occurs more often with shorter caption segments, but that is not true of all of the left justified captions.

I have tried end-padding the display segments with spaces (min length 70), but that had no effect.
HLS has a consistent caption display,

Video stream is from OBS.
Captions are being ingested via ModuleOnTextDataToCEA608.
Youtube is set to accept Embedded CEA 608/708 captions.

Is the display position set in ModuleOnTextDataToCEA608 or is it done dynamically by the YouTube player?

Any thoughts?

2

608 uses a 32 character grid and ModuleOnTextDataToCEA608 fills the caption from left to right using pop-on captions. So you would need to develop a custom version of that module to accomplish this

I think YouTube also accepts other caption formats (SRT, WebVTT), so another option would be to use WebVTT in WSE and create a WebVTT/SRT file to upload with your YouTube video. This would also take some custom work

I provide consulting services and am very experienced with captions, WSE etc. Feel free to reach out to me

ScottK
scott@blankcanvas.video