Bug 183085 – [GStreamer][GTK][Stable] Seek broken on YouTube

• Status: RESOLVED
• Resolution: WONTFIX
• Component: Media

[Michael Catanzaro]

Yes, it's bug #182936, back again!

This issue seems to be present in 2.18.6 as well, but I can only reproduce in elementary OS, which uses GStreamer 1.8.3 and *does* have gstreamer1.0-libav. We should fix it here too. I'm filing a new bug because I'm not confident that r228603 will backport cleanly or fix the issue on this branch (have not checked).

[Michael Catanzaro]

In constrast, it's working perfectly fine for me on Fedora 27 (2.18.6 with GStreamer 1.12.4 and *no* gst-libav).

[Philippe Normand]

I don't support GStreamer < 1.12. Sorry.

[Michael Catanzaro]

Created attachment 334539 [details]
Debug log

Here's a debug log where I start playing a YouTube video, attempt to seek once, and then close Epiphany. The seek fails.

(Note: the criticals at the top are an ancient Epiphany bug, should be ignored.)

[Michael Catanzaro]

(In reply to Philippe Normand from comment #2)
> I don't support GStreamer < 1.12. Sorry.

Do we need to tell them to upgrade? They might be willing to if we suggest it. It's ABI-compatible, right?

[Philippe Normand]

(In reply to Michael Catanzaro from comment #4)
> (In reply to Philippe Normand from comment #2)
> > I don't support GStreamer < 1.12. Sorry.
> 
> Do we need to tell them to upgrade? They might be willing to if we suggest
> it. It's ABI-compatible, right?

Yes and Yes.
Perhaps they can wait March though, 1.14 should be released soon.

[Michael Catanzaro]

IMO this is urgent, there should be no waiting when YouTube is broken!

My concern, though, is that it's sort of supposed to be an LTS distro. They've made a major exception for WebKit. I'm not sure if they're going to want to pull GStreamer from newer versions of Ubuntu. I can ask, though. More likely, they'll want to downgrade WebKit, reintroducing security vulnerabilities, to avoid the need for a newer GStreamer, which would be reasonable and probably what I would do in their shoes. But we'll see....

Any chance you see anything obviously broken in the log, like you did last time I posted a debug log? I looked myself, but nothing stood out to me. E.g.:

0:00:03.186149502  2159 0x5616426b2d20 INFO       webkitmediaplayer MediaPlayerPrivateGStreamer.cpp:479:seek: [Seek] seek attempt to 26.376896 secs
0:00:03.186201608  2159 0x5616426b2d20 DEBUG      webkitmediaplayer MediaPlayerPrivateGStreamer.cpp:322:playbackPosition: Position 0:00:00.529842000
0:00:03.186213097  2159 0x5616426b2d20 INFO       webkitmediaplayer MediaPlayerPrivateGStreamer.cpp:489:seek: [Seek] seeking to 0:00:26.376896000 (26.376896)

Clearly not the same problem as bug #182936.

[Philippe Normand]

That means the seek event is sent to playbin but it fails at a different level. I won't devote any time to this issue, sorry again :)

[Jeremy Bicha]

Michael, sorry for the delay in looking into this. It's a busy week in Ubuntu development.

We had an Ubuntu 17.10 user report what sounds to me like this issue today at https://launchpad.net/bugs/1752197

I can verify the issue even with Ubuntu 18.04 Alpha with epiphany 3.27.90 and webkit2gtk 2.19.90.

(As you may remember, Ubuntu has to set -DUSE_GSTREAMER_GL=OFF but maybe that won't be necessary in 18.04 soon… I haven't tried recompiling with that option disabled yet to see if it makes a difference.)

Test Case (as I reproduced the issue)
=========
Visit YouTube.
Play a video. (This works normally.)
Pause the video then unpause.
The audio plays and YouTube's time indicator ( 0:55 / 3:20) updates but the video itself remains frozen at the paused frame.

[Michael Catanzaro]

(In reply to Jeremy Bicha from comment #8)
> I can verify the issue even with Ubuntu 18.04 Alpha with epiphany 3.27.90
> and webkit2gtk 2.19.90.

That's probably bug #182936, though. It has pretty much the same symptoms. Should be fixed in 3.27.91.

> (As you may remember, Ubuntu has to set -DUSE_GSTREAMER_GL=OFF but maybe
> that won't be necessary in 18.04 soon… I haven't tried recompiling with that
> option disabled yet to see if it makes a difference.)

Oh, that is another big difference. I had forgotten. Nobody is testing that except Ubuntu. :(

If GStreamer 1.14 makes it into 18.04, then you should definitely drop that build flag. But I wouldn't hold my breath, since they are on 1.13 now. I'm afraid I have lost confidence in the GStreamer development schedule. I think we will stop using unstable GStreamer releases in the GNOME modulesets....

> Test Case (as I reproduced the issue)
> =========
> Visit YouTube.
> Play a video. (This works normally.)
> Pause the video then unpause.
> The audio plays and YouTube's time indicator ( 0:55 / 3:20) updates but the
> video itself remains frozen at the paused frame.

Yes, I would try again with 2.19.91. I think it will be fixed there, but if not, then we can reopen this for further investigation.

[Michael Catanzaro]

(In reply to Michael Catanzaro from comment #9)
> That's probably bug #182936, though. It has pretty much the same symptoms.
> Should be fixed in 3.27.91.

I meant 2.19.91.

[Michael Catanzaro]

(In reply to Michael Catanzaro from comment #9)
> If GStreamer 1.14 makes it into 18.04, then you should definitely drop that
> build flag. But I wouldn't hold my breath, since they are on 1.13 now.

I meant 1.13.1. Version numbers are hard, apparently.

[Jeremy Bicha]

(In reply to Michael Catanzaro from comment #10)
> (In reply to Michael Catanzaro from comment #9)
> > That's probably bug #182936, though. It has pretty much the same symptoms.
> > Should be fixed in 3.27.91.
> 
> I meant 2.19.91.

Sorry, not fixed yet with 2.19.91

[Michael Catanzaro]

(In reply to Jeremy Bicha from comment #12)
> (In reply to Michael Catanzaro from comment #10)
> > (In reply to Michael Catanzaro from comment #9)
> > > That's probably bug #182936, though. It has pretty much the same symptoms.
> > > Should be fixed in 3.27.91.
> > 
> > I meant 2.19.91.
> 
> Sorry, not fixed yet with 2.19.91

Yes, I noticed that earlier today, and reopened bug #182936.