Bug #2788
closed
teletext subtitle decoding does not work, sample included.
Added by danny skjodt about 10 years ago.
Updated almost 10 years ago.
Estimated time:
(Total: 0:00 h)
Found in version:
git from yesterday
Description
Hey ive got a sample here from a tv channel where subs only works if you take it out from tvheadend as pass, using matroska leaves empty subs.
Files
What does mkvinfo say about the recorded file ? Note that tvheadend stores subtitles ASIS with type S_DVBSUB . ffmpeg can handle them, but most players can't.
Jaroslav Kysela wrote:
What does mkvinfo say about the recorded file ? Note that tvheadend stores subtitles ASIS with type S_DVBSUB . ffmpeg can handle them, but most players can't.
My player is XBMC, its pretty simple to reproduce, hook up the ts file as a channel, and try with vlc first to get it out as pass, then matroska, the last one will have empty subs.
I believe that the S_DVBSUB track is in the matroska stream, but the player does not handle it correctly. Just look to the matroska file using mkvinfo.
Jaroslav Kysela wrote:
I believe that the S_DVBSUB track is in the matroska stream, but the player does not handle it correctly. Just look to the matroska file using mkvinfo.
Yes the subtitle tracks is in the stream, but they are empty, nothing shows up when you select em, tvheadends matroska muxer fails to mux then in a way that players like vlc and xbmc that else have no problems with matroska subs shows no subs.
I think its pretty clear that tvheadends matroska muxer fails to mux these subs properly as mux pass works, and mux matroska leaves empty subtitles, you can select subtitle yes but no subtitles shows up.
Here is a sample recorded in mkv from that channel, vlc would normaly play those text subs fine but they are empty ? :)
OK, so these subtitles are from teletext. Any teletext related errors in the log ?
Jaroslav Kysela wrote:
OK, so these subtitles are from teletext. Any teletext related errors in the log ?
Nope no errors and sample.ts play fine and shows the subs using various players :/
danny skjodt wrote:
Jaroslav Kysela wrote:
OK, so these subtitles are from teletext. Any teletext related errors in the log ?
Nope no errors and sample.ts play fine and shows the subs using various players :/
It gets even more strange, found out that in xbmc you can activate text tv, then find the right page and teletext works, but the ones tvheadend demuxes from the telx pid you can choose with L key or Subtitle button is still empty.
Just a little note: The MPEG-TS teletext packets in the provided .ts sample are not parsed by current tvheadend at all (another packing system), so the subtitles are not decoded from teletext. I need to find what's packing scheme is used.
- Subject changed from subtitle muxing dont work, sample included. to teletext subtitle decoding does not work, sample included.
- Status changed from New to Fixed
Applied in changeset commit:tvheadend|200ba1f28c3567c8eff2a02d4026932faf276012.
Fixed in v4.1-209-g200ba1f .
Jaroslav Kysela wrote:
Fixed in v4.1-209-g200ba1f .
Tested and works, manny thanks :)
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Updated by Jaroslav Kysela almost 10 years ago