Bug 177976 – [MSE][GStreamer] Seek on youtube.com/tv fails after r217185

• Status: RESOLVED
• Resolution: FIXED
• Component: Media

[Enrique Ocaña]

http://trac.webkit.org/changeset/217185 added an extra call to MediaSourcePrivate::waitForSeekCompleted() on MediaSource::seekToTime() that our MediaPlayerPrivateGStreamerMSE (the final receiver) isn't expecting. This is completely breaking the seek behaviour because, unlike MediaPlayerPrivateMediaSourceAVFObjC, the GStreamer MSE player private doesn't have an internal seek state to distinguish the original call from the new one.

[Enrique Ocaña]

Created attachment 322931 [details]
Patch

[Jer Noble]

Sorry about that!  But keep in mind, there are some WebGL conformance tests that require that the <video> element has a decoded frame available as soon as the "seeked" event fires.  The point of the second "waitForSeekCompleted()" was to give the private an opportunity to delay completion of a seek until it's had a chance to decode the frame at the seeded time.  So you may want to look into adding that kind of behavior to the GStreamer back-end.

[Enrique Ocaña]

Thanks for pointing it out. However, by now our priority should be to put MSE in GStreamer on a better shape (lots of w3c tests failing, webm support, still some seek corner cases). Then we can focus on proper interoperation with other parts of webkit (WebGL, as you mention).

[WebKit Commit Bot]

Comment on attachment 322931 [details]
Patch

Clearing flags on attachment: 322931

Committed r222966: <http://trac.webkit.org/changeset/222966>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.

[Radar WebKit Bug Importer]

<rdar://problem/34851779>