GNOME Bugzilla – Bug 793323
iOS 11.2 vtdec ! glimagesink decoding broken on iphone 6
Last modified: 2018-11-03 14:17:48 UTC
In iOS 11.2.5 testing with GStreamer 1.12.4 on an iPhone 6, I'm currently seeing that vtdec ! glimagesink output plays incorrectly, with frames showing out of order. It only happens with GL output from vtdec, and I suspect is related to the GL textures being invalidated too early, or otherwise not having the content we think they do. The same build works fine on an older ipad3 with iOS 9.2, and since the latest work on vtdec references iOS 11.1, I suspect it worked there and is therefore possibly an iOS change we need to find a solution for. Has anyone else been testing on iOS 11.2 recently?
I had a chance to test decoding on an iPhone 7, and it *does not* show the same behaviour - video decoding seems to work fine there with iOS 11.2.5.
I think the problem is specific to iphone 6 (or lower?), and seems to be about how long textures are valid for. Simply doing vtdec ! videorate ! glimagesink makes things work - and I suspect it's because videorate holds a reference to the video buffer until the next one arrives.
Is this a regression on our side also, or only on Apple's side?
I have no way to tell.
Do you have any ideas where to look / things left to try? Not sure I want to block the release on this, esp. if it only happens with some/older devices.
Oh, but it happens with 1.12 as well, so not really a blocker anyway I guess, other than in the sense that it would be nice to fix.
Yes, not a blocker. If it's a regression, it's not a very recent one, and afaict I'm the first to notice it.
I have some (third party) results that indicate that the problem starts to occur on the iPhone 6/6S/6+ between iOS 10.3.1 and iOS 11.2.5 which would indicate a regression in the underlying OS/frameworks.
-- GitLab Migration Automatic Message -- This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity. You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/issues/653.