GNOME Bugzilla – Bug 615154
A lot of frames are dropped during playback after a gap in the timeline
Last modified: 2014-11-06 20:36:14 UTC
If pitivi plays a clip after leaving an area without any clip then the playback is broken. Frames get dropped in the audio and video tracks, though the effect seems to be independent of each other. Steps to reproduce: 1. Import a video file (DV in our case) and inser it in the timeline at the start 2. Playback video, this is smooth 3. Move clip away from the start of the timeline 4. Start playback from a few seconds in front of the clip Only restarting pitivi fixes the problem. Adding a black PNG file and a silent audio track in the background of the whole video works around the issue. Pitivi master (7cbb64f803e7575ed3967936409aa3c754732923), and: bluez-gstreamer 4.51-0ubuntu2 gstreamer0.10-alsa 0.10.28-1~karmic2 gstreamer0.10-ffmpeg 0.10.10-1~karmic1 gstreamer0.10-fluendo-mp3 0.10.12.debian-2~karmic1 gstreamer0.10-gnonlin 0.10.15-1~karmic1 gstreamer0.10-nice 0.0.9-2 gstreamer0.10-plugins-bad 0.10.18-2~karmic1 gstreamer0.10-plugins-bad-multiverse 0.10.13-0ubuntu1 gstreamer0.10-plugins-base 0.10.28-1~karmic2 gstreamer0.10-plugins-base-apps 0.10.28-1~karmic2 gstreamer0.10-plugins-good 0.10.21-1~karmic1 gstreamer0.10-plugins-ugly 0.10.14-1~karmic1 gstreamer0.10-plugins-ugly-multiverse 0.10.12-0ubuntu1 gstreamer0.10-pulseaudio 0.10.21-1~karmic1 gstreamer0.10-tools 0.10.28-1~karmic2 gstreamer0.10-x 0.10.28-1~karmic2 libgstreamer-plugins-base0.10-0 0.10.28-1~karmic2 libgstreamer0.10-0 0.10.28-1~karmic2 Pitivi is slightly patched, eg. to use ximagesink instead of xvimagesink as XVideo is having problems on the machine.
I guess this could be related to bug #610077.
Or bug #613416 maybe?
I don't think this is bug #613416. Performance *changes at runtime* after a certain condition was met. Also, we now noticed that this is not just the playback that gets broken. For whatever reason, rendering a project with such a clip results in a file with a 30fps video track, instead of the 25fps that are selected in the project. The same workaround, ie. adding a black image in the background, works fine too.
I did notice often that QoS kicks-in when you go from one clip to another (even if they're snapped together), but I don't know if that's the same thing (probably).
I have the gap bug also when the gap is located between 2 clips. The previewer lags when 2 clips are not exactly one after the other, so it lags when there's a gap between 2 clips, no matter if the 2 clips are on the same layer or not. See the following screencast that illustrates this bug: https://bugs.launchpad.net/ubuntu/+source/pitivi/+bug/608898/+attachment/1773347/+files/pitivi-lag.ogv My config: PiTiVi 0.13.5., Ubuntu 10.10
Not sure if this still happens with 0.14, but this problem might disappear when pitivi gets ported to GES.
I have this problem on 0.15.0 and also leads to all sorts of stability issues. Even worse, it makes rendering stop if such gaps exist. If there is a second continuous audio track and a video (of an image file) the stability improves, but still, the preview is bad and rendering breaks. Oddly enough, if the gaps are removed and rendering is successful, there can be occasional glimpses of the image. Could that be related to the black frame bug?
AFAIK the black frame bug is a different issue... (which I haven't seen so far in the GES version). Anyway, this bug (and many other playback/rendering-related bugs) will need to be tested again after the switch to GES is complete. Sadly we can't investigate much bugs that occur on the "traditional" core of PiTiVi at this point because all efforts are focused on the GES version (which is due to be release for GNOME 3.4, but hopefully there should be some testing releases before then).
Hi there, As Pitivi 0.91 has now been released, we would like to encourage you to test it. It is quite possible that your issue is fixed in this version, as it is a very significant technical overhaul compared to the 0.15 series. Read more about the 0.91 release here: http://wiki.pitivi.org/wiki/0.91 If you can reproduce this bug against 0.91 or newer (such as the git version), please update this bug report accordingly with detailed instructions to reproduce the bug, updated sample files/projects in xges format, etc. Drop by our IRC channel if you need help getting started or want to help out! Thanks!
Closing this bug report as no further information has been provided. Please feel free to reopen if the issue persists with 0.94 or newer and if you can provide the information asked for. Thanks!