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v2.0.2: does not display time properly

Posted: 07 Jul 2012 02:15
by ixodid
I downloaded an .ogv file that is 2:32:00 long. Just skimming through it, it seems to be complete and plays fine, but the total time displayed in the box in the lower right-hand corner reads 1:30:00.

When I move my mouse pointer along the playback progress line, the mouse-over time displayed corresponds with the 1:30:00 scale. But the time is displayed correctly in the elapsed section of the time box. So if I am playing near the end of the video, the time display reads, for instance, 2:24:00/1:30:00.

Is there a way to make the time display correctly?
____

EDIT: Now that I've played through much of the video, I'm finding that:

1) The video skips forward occasionally
2) The elapsed time freezes and then skips ahead about every 10 - 15 seconds

Thoughts, please?

Re: v2.0.2: does not display time properly

Posted: 07 Jul 2012 11:31
by nkoriyama
Known issue.ticket 6983
At the moment, if you use avformat demuxer, you can see the correct time.

Re: v2.0.2: does not display time properly

Posted: 07 Jul 2012 17:05
by ixodid
Thank you for your answer. Is avformat demuxer a download or option? I followed the ticket 6983 link but did not understand it.

And, will it take care of the content skipping issue?

Re: v2.0.2: does not display time properly

Posted: 07 Jul 2012 22:47
by nkoriyama
Preferences -> All -> Input / Codecs -> Demuxers
Demux module

Re: v2.0.2: does not display time properly

Posted: 07 Jul 2012 23:49
by ixodid
Preferences -> All -> Input / Codecs -> Demuxers
Demux module
I do not find Demux module there...

Re: v2.0.2: does not display time properly

Posted: 08 Jul 2012 05:02
by nkoriyama
Image

Re: v2.0.2: does not display time properly

Posted: 08 Jul 2012 05:05
by nkoriyama
I don't recommend always using Avformat demuxer.
Please use it for experimental purpose only.

Re: v2.0.2: does not display time properly

Posted: 08 Jul 2012 13:33
by ixodid
I set to AVformat demuxer and not the file will not play at all.

Will the demuxer (if I can get it to work) take care of the content skipping issue? I ask because the more important issue is that I be able to hear the file unbroken.

Is there another method I could try? Should I download that file again? Perhaps edit the file to break it into two or more parts?

Thank you for your help.

Re: v2.0.2: does not display time properly

Posted: 01 Oct 2012 18:34
by amartin
Hello,

I am trying to run VLC playing a RTP + MpegTS + H264 stream (provided by a simple Gstreamer pipeline) represented by an SDP.

I have already checked that the MpegTS timestamps are there with a "timeoverlay" element in a gst pipeline.

It is played correctly by VLC but the displayed time is always 00:00 when "Default Demuxer" is set.

If I set "avformat" demuxer the following error is thrown by the VLC message log:
avcodec debug: couldn't guess format
main debug: no demux module matching "avcodec" could be loaded

My feeling is that AVformat demuxer can deal with MPEGTS, but RTP/RTSP live 555 (default) deals with RTP. RTP live555 demuxer is not able to take neither MPEGTS nor RTP timestamps. Isn't it?

Have somebody achieved to play an RTP + MpegTS stream in VLC with the MpegTS stream time?

Thank you in advance for your help.

Re: v2.0.2: does not display time properly

Posted: 01 Oct 2012 21:45
by Rémi Denis-Courmont
VLC always uses the MPEG-TS PCR when dealing with MPEG-TS, including over RTP, ignoring the RTP timestamp. For normal (elementary) RTP streams, RTP timestamps are correleated with RTCP-SR. Thus, you cannot synchronize MPEG-TS (over RTP) with something else (over RTP).

Re: v2.0.2: does not display time properly

Posted: 02 Oct 2012 08:57
by amartin
Dear Rémi,

Do you mean that if I achieve to include MPEG-TS PCR data in the RTP+MPEG-TS stream, VLC will display this time?

If I have understood you correctly I can just analyse or modify, if necessary, the Gst mpegtsmux plugin. This is not a big hurdle from my side.

Thank you.

Re: v2.0.2: does not display time properly

Posted: 03 Oct 2012 12:51
by amartin
This live streaming RTP+MPEG-TS issue is being tracked in VLC 2.0.3 in windows so I continue this thead in:
viewtopic.php?f=14&t=104760&p=354750#p354750

Re: v2.0.2: does not display time properly

Posted: 03 Oct 2012 16:46
by Jean-Baptiste Kempf
Please do not cross post.

Re: v2.0.2: does not display time properly

Posted: 03 Oct 2012 17:47
by Rémi Denis-Courmont
I don't understand the question.

Re: v2.0.2: does not display time properly

Posted: 04 Oct 2012 09:02
by amartin
The question was just to get confirmation that a proper PCR data embedded in the MPEG-TS stream should enable correct VLC current time display (PSI like for DVB) regardless of UDP and RTP communication protocol.

Re: v2.0.2: does not display time properly

Posted: 04 Oct 2012 16:55
by Rémi Denis-Courmont
I still don't understand the question.

Re: v2.0.2: does not display time properly

Posted: 04 Oct 2012 17:45
by amartin
I am streaming a live video flow over UDP with RTP encapsulation.

The scenarios is: if the server start to stream an event at 17h15m00s. Then at 17h30m00s when a VLC client connects to this stream (through an SDP) I'd like VLC to display 00:15:00 ... :01 ... :02... and so on. Now it always shows 00:00 all the time.

Is there an specific pair (encapsulator and codec) to achieve it? MPEG-TS and H.264 stream timestamps are not managed/displayed properly by VLC.

I checked that for a real DVB broadcasted signal the time is correctly displayed based on PSI data. I want the same for custom UDP live stream.

I also know that if the stream is generated by VLC employing RTSP + MPEGTS + H264 (for example) the time is displayed in the VLC client correctly, but i need to use RTP (UDP).

I hope that now it is more clear.

Re: v2.0.2: does not display time properly

Posted: 04 Oct 2012 19:29
by Rémi Denis-Courmont
VLC uses the same DVB meta infos that digital TVs do, to find the display time. This has nothing to do with PCR.

If it's missing, VLC simply cannot compute the time.

Re: v2.0.2: does not display time properly

Posted: 16 Dec 2012 02:58
by dmitche3
Sorry if this was answered but I couldn't follow the thread very well. Is there a ticket to fix the elapsed time so that the proper time is displayed or was the solution given? I tried using the solution given and performance was so bad (slow) that I was running probably close to 1 frame per second. Other demuxer options caused vlc to freeze up or just didn't do anything.

Thanks.