Jump to content

Captions do not appear during Live TV playback, but DO play during playback of RECORDED TV


Recommended Posts

I'm trying to watch Live TV (via Emby's native Hauppauge device support) with closed captions (ATSC Closed Captions, NOT subtitles) in the Apple TV client but I can't seem to find any combination of settings that cause them to appear. I don't even get a "Subtitles" option from the top pull-down menu. Even more perplexingly, they appear and work just fine when playing back recorded content from the same tuner and channel. (The content was recorded by Emby) When playing this back, I DO get a "Subtitles" option from the top pull-down menu which gives me the selections: "Off", "Auto", and "CC". I have attached ffmpeg logs of the Live TV transcode that fails to provide captions and the recorded content transcode that succeeds. They seem to be nearly identical. I also have attached the general server log.


Additionally, if I get the transcoded Live TV stream from Emby's logs and play it in VLC while Emby is playing it, VLC allows me to enable closed captions just fine. So it appears they they are NOT lost in the transcode and, for whatever reason, the Live TV player is incorrectly forbidding me from enabling closed caption display. I believe Apple's player handles CC natively so I would hope that this is just a matter of not forcing captions to be disabled.


As a side note, captions only work properly with the "Standard" deinterlace mode, the bob-and-weave mode causes the caption contents to 'double-up' in a peculiar way. I don't think this is your fault (or anyone's, really). The way the bob-and-weave deinterlace yields two frames per interlaced frame seems to duplicate the caption data, as it is encoded into the frames themselves somehow. Worth knowing if you're trying to reproduce and see wacky looking captions.

FFMpeg With Captions.log

FFMpeg No Captions.log


Link to comment
Share on other sites

@@Luke, it doesn't show me available subtitle streams for either of Live TV or recorded TV in the web player.


Additionally, if I disable the Apple TV's built-in Closed Captioning processing (Settings -> General -> Accessibility -> Subtitles and Captioning, toggle 'Closed Captions and SDH' to 'Off'), the captions in prerecorded content no longer appear. However, if I select 'CC' from the Subtitles section of the top pull-down menu after having done this, the captions appear again. (This doesn't seem to affect the Apple TV's setting at all) Which is what has been leading me to believe that the Apple TV's native player just sort of does this on its own when it thinks it's allowed (the displayed Closed Captions follow the styling I set in the Apple TV's subtitle settings, but it seems Emby just does this in general). If I change the Apple TV's setting back to 'On', the player for prerecorded content within Emby selects 'CC' automatically.


Also if I play the captioned content in VLC but ALSO add a 'real' subtitle track it treats them as separate things (and renders them quite differently).


I'd be willing to try any beta version of the Apple TV client that experimentally enabled selecting any possible detected 'subtitles' for Live TV (to give one the option to pick their 'CC' option) and report back if that's possible.

Edited by KazPinkerton
Link to comment
Share on other sites

Ok so then yes, Ebr is correct here. We still have a little bit of work to do regarding closed captions. As you might know, closed captions are not the same thing as subtitles. We obviously fully support subtitles. Depending on the source of your live tv stream, the closed captions could come in either form, and in subtitle form they are already supported. But when they are true closed captions, we still have a little work to do. Thanks.

Link to comment
Share on other sites

  • 3 years later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Create New...