Is Black-Magic Support Close Caption?

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pankajMahan

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  • Joined: Thu Apr 26, 2018 6:27 am
  • Real Name: Pankaj Kumar

Is Black-Magic Support Close Caption?

PostThu Apr 26, 2018 6:38 am

Hi,

Do Blackmagic provide any API in their development SDK to pass close caption alongside video or any other API to burn the close-Captions in the video? I'm using C++ develpment SDK of Blackmagic.

Thanks,
Pankaj Kumar
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Cameron Nichols

Blackmagic Design

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Re: Is Black-Magic Support Close Caption?

PostFri Apr 27, 2018 3:50 am

Hi Panjak,

Yes, it is possible to embed Closed Caption (CEA708), encoded as SMPTE 292M packets as VANC output.

Refer to:
  • DeckLink SDK Manual - 2.4.7.2 VANC Output high level overview
  • ClosedCaptions SDK sample (Mac/Win/Linux)
Regards
Cameron
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pankajMahan

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  • Real Name: Pankaj Kumar

Re: Is Black-Magic Support Close Caption?

PostMon Apr 30, 2018 6:51 am

Thanks, Cameron
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pankajMahan

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  • Real Name: Pankaj Kumar

Re: Is Black-Magic Support Close Caption?

PostWed May 02, 2018 6:05 am

Hi Cameron,

I tried ClosedCaptions SDK sample for windows. I'm using a black-magic 4K card and 4k Samsung monitor and they are connected via HDMI port. But problem is that I didn't see any closed caption on the monitor. It just shows three blue frames.

Any kind of help will be appreciated.

Thanks,
Pankaj Kumar
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Cameron Nichols

Blackmagic Design

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  • Joined: Mon Sep 04, 2017 4:05 am

Re: Is Black-Magic Support Close Caption?

PostFri May 04, 2018 1:41 am

Hi Panjak,

Let me elaborate on my previous post. Closed Captions is supported on SDI as it follows the SMPTE ST 334 specification for transmitting in VANC for HD, or LINE21 for NTSC.

There is no equivalent standard for transmitting Closed Captions over HDMI, it is the responsibility of the content providers to decode Closed Captions within the Set Top Box.

Regards
Cameron

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