How do you insert Closed Captions in your TV broadcast solutions?

We are looking for some solution that will insert VANC data (OP47 teletext or 608) into SDI, ideally using BMD Decklink cards and insertion should be on thy fly. Automation will send via REST API the text that should be displayed (inserted) to VANC.

Or we are opened to any solution that you already use in your project to embedd CC to your broadcast (even not SDI)


This has been disussed multiple times in the forum. You can use the little magnifying glass icon to search for „close caption“ and find the other treads.

Thanks for hint Didi :slight_smile: Unfortunately I have not found solution in the forum, I am looking for even pro solution which maybe some of CasparCG users already found. We have succesfully implemented integration with Playbox Subtitler, but it is still quite expensive solution for most clients.

CC is, like Teletext, something, that is inserted in TV lines in the area outside of the visible display. AFAIK Decklink cards do not support this. So you need to use something, that uses a card, that can inserts data outside of the display area. As Caspar only supports Decklink and Bluefish, you may be out of luck.

As far as I’m aware, this is something that has been asked for a few times, but noone has contributed or funded an implementation, so no progress has been made.
There is a github issue discussing this Playback/record of 608/708 CC and VANC · Issue #92 · CasparCG/server · GitHub

I am pretty sure that decklinks can do it, the specs do say:

SDI Metadata Support
RP 188/SMPTE 12M-2 and closed captioning.

but I haven’t tried it so can’t say for certain. I did do RP188 in the NRK 2.1, but that is much simpler and hasn’t made its way upstream

Almost all modern BMD cards supports VANC insertion (these TV lines outside visible display). Even their SDK is pretty well documented, but spec of 608/708 is really huge and we are not able to implement it by our own, so I was looking even for some affordable business solution and as far as I found was from Playbox (about 10k € per channel) where we can utilize BMD Duo cards and loopback output from CasparCG SDI OUT to SDI IN (insert VANC based of SRT files) and OUT again to distribution.

I will be glad if someone, who have faced this problem in some project, can guide me to more affordable solution.

Thanks guys.

Thanks for clarification. We are able to fund an implementation to Caspar, so if someone is interested, please leave me a message. Thank you.