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I wish to decode 608/708 captions from an HEVC encoded video wrapped within an MPEG TS stream. I cannot find any information as to how to locate the closed caption data. Is anybody able to provide any assistance with this regard?

Bastian35022
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ManicsMan
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I guess HEVC streams store CEA 608/708 captions in SEI T35 registered data, like H264 does. May be you could add a link of the HEVC stream to help confirmation.

sym39
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  • Thanks for the reply. I did look for SMPTE 291M packetization of the captions as used in H264 but could not find them. I am not sure what SEI T35 is. The file that I am trying to extract captions from can be downloaded from https://drive.google.com/file/d/0Bz6rufqGlwtLS3kyUVBYSVR5YW8/view?usp=sharing – ManicsMan Oct 13 '14 at 02:53
  • For CEA 608/708 and how they are embedded in H264 streams, look at http://www.atsc.org/cms/standards/a72/a_72_part_1.pdf, 6.4. – sym39 Oct 17 '14 at 09:44
  • For SEI, you can have a look at H264 and or H265 specification (look for user_data_registered_itu_t_t35). About the ts file you provided, I was unable to find any H265 SEI, and my analyzer reports some errors on the PES payload, so if subtitles are present, they may be located there, may be stored in an other way (ie, not in SEI). Additionally, I didn't found any TS descriptor that may announce how the caption are stored. – sym39 Oct 17 '14 at 09:52