[fixed] [MP2-611] Having problems with subtitles (ATSC) (1 Viewer)
- Thread starter Gcarr
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@aspik I'm testing it now. Initially my screen froze a few minutes after I started. I rebooted and so far it's been 30 minutes and that problem hasn't come back. The only thing I notice is that I can't turn off ATSC subtitles from the Player Configuration Menu. I have to go back into settings to turn them off. Clicking on the Subtitle option in Player Configuration brings up an empty box and clicking does nothing. This problem was in the original dll also. I attached a screenshot of the menu so you can see what I am talking about. This is not a big problem for me, I appreciate your working on this so quick!
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Yes, I know. The problem is, we are not able to know if the played TS file contains ATSC subtitles. This information is needed as we add then the CC parser to the direct show graph. Our current implementation is mainly based on the setting "Enable ATSC subtitles".
@Owlsroost
checking the provided sample with mediainfo, shows that it has four "text entries". Do you think that this information can be used to know about the existence of ATSC subtitles?
VLC shows all four entries as an subtitle, but only when selecting the first one subtitles are displayed.
Even when we find a way to determine the existence of ATSC subtitles, I don't know how we should implement the "No subtitles" option. The CC parser is added while to video is about to start to play, we can't just remove it from the graph. So in best case, you'll have to stop the video and play it again.
- September 1, 2008
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The PMT video stream includes a caption service descriptor. For information about this descriptor please refer to ATSC A/65 section 6.9.2:
https://www.atsc.org/wp-content/upl...tocol-for-Terrestrial-Broadcast-and-Cable.pdf
In short: that descriptor should enable TsReader to determine how many closed captions streams/services there are, what language the caption streams/services are, and whether the caption streams/services are digital (EIA/CEA-708) or analog (EIA/CEA-608).
It might be better (more accurate) if TsReader were able to check the EIT (EPG data), because some channels only have captions for specific events/shows. According to the linked standard, the broadcaster may or may not remove the descriptor from the PMT... but they must include the same descriptor for each event/program/show that has captions, and not include it for events/programs/shows that don't have captions. On the other hand, EIT/EPG data for ATSC is notoriously bad (inaccurate)... and TsReader doesn't have access to it.
@morpheus_xx
The provided .dll has the "old" check against the ATSC subs option. I realized that the method AddEvr() (where _closedCaptionsFilterAdded was evaluated in order to increment the stream count) is executed before AddSubtitleFilter (where _closedCaptionsFilterAdded was set) from TsVideoPlayer. So, even if we could know if the played TS stream has ATSC subs, we would know it too late to do something with this information.
I pushed this fix to the teletext branch. If you do not have a better idea how to solve this nicer, I'll merge this to wip 2.2.2 and we have to accept that the option ATSC subs should be enabled only by users who can receive ATSC subs.
The provided .dll has the "old" check against the ATSC subs option. I realized that the method AddEvr() (where _closedCaptionsFilterAdded was evaluated in order to increment the stream count) is executed before AddSubtitleFilter (where _closedCaptionsFilterAdded was set) from TsVideoPlayer. So, even if we could know if the played TS stream has ATSC subs, we would know it too late to do something with this information.
I pushed this fix to the teletext branch. If you do not have a better idea how to solve this nicer, I'll merge this to wip 2.2.2 and we have to accept that the option ATSC subs should be enabled only by users who can receive ATSC subs.