Problem with subtitles on recording playback

[uglyned]

Hi,

 

It seems like Teletext:888 subtitles don't play back quite right on recordings - they appear maybe 3 or 4 seconds earlier than they should.

 

If I watch a TV show live then the subs appear exactly when they should but if I record the programme and watch the subs, they appear maybe 3 or 4 seconds early.

 

That makes them useless because they don't appear at the same time as the speech.

 

I prefer the teletext:888 subtitles because they appear on the screen without the black background. If I select DVB subtitles they have the black background which, strangely, look like teletext. Are they definitely the right way around.

 

Let me know if there's anything else you need - maybe a quick recording or something?

[Zathras]

Just want to say I have the same problem with teletext subtitles when watching recorded material. Here I'd say the subtitles are around 2 seconds too early, that's mostly tolerable but still quite annoying. DVB subtitles always come up good but many channels only have the teletext subs option.

 

For what it's worth, my hardware is Terratec Cinergy C PCI HD + CI Addon and apart from this issue I haven't really had any problems.

Edited July 8, 2009 by Zathras

[Zathras]

In case it matters, I decided to create a support.zip file of my system as attached.

 

Again, I use Terratec Cinergy C PCI with CI Addon; driver version is 1.1.0.601 .

 

Guess this isn't such a common issue after all. Annoying, nevertheless.

support.zip

[IRa]

Here I'd say the subtitles are around 2 seconds too early,

If you are talkinga about Finnish YLEs prodcast they don't send teletext subtitles at right time in DVB-T or C (they send them for DVB-S uses only)

[Zathras]

If you are talkinga about Finnish YLEs prodcast they don't send teletext subtitles at right time in DVB-T or C (they send them for DVB-S uses only)

But I'm talking about pay-tv channels such as Canal+.

[uglyned]

For me it was Teletext:888 subtitles on BBC2 England.

[Zathras]

This issue had been somewhat less noticeable for me lately for whatever reason, until I had to recently reinstall DVBViewer due to unrelated reasons. Now the problem's back, teletext subtitles are definitely 2-3 seconds ahead of the spoken lines and the problem occurs only when watching recorded shows. No sync issues with live tv, nor with DVB subtitles.

 

The weird thing is the subtitles are perfectly in sync when I open a recording in TSPlayer so I don't think it's the actual recordings that are sync-broken but the way DVBViewer opens and/or views them. I would happily watch those recordings within TSPlayer if I could make the teletext screen transparent -- it's always just a big black box blocking almost the whole screen (opaque/transparent checkboxes in Videotext tab do nothing, I don't know if they should).

 

So I'd like to make either (in order of preference):

- DVBViewer to show recorded teletext subtitles in good sync, or

- TSPlayer to show teletext subtitles in a transparent background.

 

Should be possible, right?

[Zathras]

Wow, I never knew VLC player supports teletext subtitles. I actually demuxed a file to get an srt subtitle so that I'd check if it works in VLC when I suddenly saw that you can directly select teletext subtitles in VLC, and the sync is perfect. This made my day, I don't necessarily need to watch the stuff in DVBViewer.

Edited February 21, 2010 by Zathras

[Griga]

I would happily watch those recordings within TSPlayer if I could make the teletext screen transparent -- it's always just a big black box blocking almost the whole screen

TSPlayer only supports transparent teletext subtitles in overlay mode (Settings -> Renderer -> Video -> Overlay Mixer).

 

Anyway... teletext subtitles are not explicitely synchronized with video/audio, neither in TSPlayer, nor in DVBViewer, which means, the time stamps are not considered. Teletext is displayed when it arrives. So this issue

 

teletext subtitles are definitely 2-3 seconds ahead of the spoken lines

may be caused by delayed video/audio, e.g. due to extensive buffering in the DirectShow filtergraph (a kind of unwanted timeshift), and it may depend on the decoder/renderer selection.

[Zathras]

TSPlayer only supports transparent teletext subtitles in overlay mode (Settings -> Renderer -> Video -> Overlay Mixer).

 

Anyway... teletext subtitles are not explicitely synchronized with video/audio, neither in TSPlayer, nor in DVBViewer, which means, the time stamps are not considered. Teletext is displayed when it arrives. So this issue may be caused by delayed video/audio, e.g. due to extensive buffering in the DirectShow filtergraph (a kind of unwanted timeshift), and it may depend on the decoder/renderer selection.

Thanks for your answer.

 

Yeah, I kind of guessed it would have something to do with buffering. In any case, VLC Player gets me by OK so I don't really have to scratch my head with the issue anymore.

 

I wonder if in some future version of DVBViewer the teletext could check if the video is "late" and delay itself accordingly, or if you could adjust the "time" manually by xx seconds. Then again it seems, not too many people are having issues with it.

Edited February 21, 2010 by Zathras

[Derrick]

..is there a reason, still not to consider the time stamps? At least this is a long time known issue.

[Griga]

It's just a question of time

[Lars_MQ]

There are so many things waiting (Grigas ttx rewrite still needs to be adapted for the Pro) and there is way too little time for all... Plus Griga has to figure this out (I simply can't - not my area of expertise ) and he does it all - and lot's of things more that you don't see directly in the public - in his free time, so earning money for living has simply more priority than a hobby in such cases...

[Derrick]

I rest my case

[Zathras]

Apparently I have no trouble watching the teletext-subtitled content on DVBViewer GE either. I didn't remember there was that version as well.

 

Also, all problems I had with the (FTA) HD channels went away when I use the GE instead of the normal DVBViewer Pro. Pretty cool.

[petgox]

Wow, I never knew VLC player supports teletext subtitles. I actually demuxed a file to get an srt subtitle so that I'd check if it works in VLC when I suddenly saw that you can directly select teletext subtitles in VLC, and the sync is perfect. This made my day, I don't necessarily need to watch the stuff in DVBViewer.

Can you tell me what your recorded teletext subtitles look like in VLC player, when I play the recorded .ts file in VLC player(because of the known issues of synchronization in DVBViewer) and choose the subtitle track, it does show teletext subtitles (as you can see in the picture), I was wondering is there any way for these subtitles to be displayed not so narrowly but across the whole width of the picture, as it is displayed in DVBViewer. I tried changing few option in VLC, but unsuccessfully.

 

Thanks in advance!