GNOME Bugzilla – Bug 723447
Rendering HD videos produces a file with video part unreadable
Last modified: 2014-09-28 20:43:43 UTC
Here is a summary of a rendering issue happening only if I use HD videos. Some context: My videos come from a GoPro, which by default saves the video in full quality (here 1080p, that is 1920×1080, 60 fps) and another one in low quality, which is very good to use when preparing a video project (here 432×240, 30 fps). If I start a new project, set up its properties manually (432×240, 30 fps, square pixel ratio, sound in 48kHz), add the low quality video and directly renders as OGV (100% video), this works, I get the expected result (see a project archive here: http://mathieu.basille.net/tmp/test1-432x240.xges_tar, and the result here: http://mathieu.basille.net/tmp/test1-432x240.ogv). Now if I do exactly the same, this time setting up the properties to HD (1920×1080, 60 fps, square pixel ratio, sound in 48kHz), and use the HD video, Pitivi does not render properly. Pitiv still proceeds with no errors, but produces a file in which the video part is unreadable (see a project archive here: http://mathieu.basille.net/tmp/test1-1920x1080.xges_tar, and the result here: http://mathieu.basille.net/tmp/test1-1920x1080.ogv). Any idea why? Thanks a lot for any suggestion. Mathieu
Forgot to say: I'm using Pitivi 0.92-1 from Debian experimental...
Same result with the latest Debian updates for video codecs. Is there anything I could do to try to debug this? This is really blocking for me since I cannot render my video projects.
1) Weird, with either the git version or Pitivi 0.92 provided by Fedora 20, if I take your project file "as is" and render without touching anything, no problem at all. I can't reproduce the issue. The resulting rendered file has a playable video stream (I can see the nice landscape in Totem). I'm not sure why you're experiencing the issue and I'm not seeing it on my side... 2) *However*, your project makes me discover another bug similar to bug #720699: if I set the project settings from the clip's properties and try to render, I experience your problem and see this in the terminal: GStreamer-CRITICAL **: gst_mini_object_unref: assertion 'mini_object->refcount > 0' failed Inspection of the differences between the two xges files shows that only the "stream-profile" section changes: Your file has: width=(int)1980, height=(int)1080, framerate=(fraction)60/1, pixel-aspect-ratio=(fraction)1/1' ...while my "broken" version creates: width=(int)1920, height=(int)1080, framerate=(fraction)60000/1001, pixel-aspect-ratio=(fraction)1/1, format=(string)I420' (note that you incorrectly set your width and framerate :) I'm suspecting that the "format=(string)I420" is the one breaking stuff. i420 is one of the possible YUV colorspace formats. This sounds like a videomixer issue. Unless we/you can find a way to reproduce the issue, so far the only bug I'm seeing is the one in 2) - if so, maybe we should retitle this bug report.
Hey Jean-François. I'm aware of bug #720699, which did affect me (with a faulty 'rate=(glong)44100'). But I don't think it is the case here. If I apply the properties of the video to the project, I get back to the error from bug #720699, not a new one. If I add the 'format=(string)I420', I also get back to the same error. On the one hand, I'm glad that you can render the video correctly! This means that, at least, it is not a general issue, and that the problem is mostly related to my system. However, I'm still not able to render correctly. I tried a couple of things directly in the xges file (using the correct dimensions...), using different framerates: '(fraction)60/1' or '(fraction)60000/1001' (which is 59.94 fps, one thing that I still don't understand), to no avail... In every case, I had the infamous message at the start of the rendering: (pitivi:22094): GStreamer-CRITICAL **: gst_mini_object_unref: assertion `mini_object->refcount > 0' failed I'm completely lost here. Is there anything I should check on my system, maybe on the GStreamer side? Thanks for any help on this, this is so frustrating not to be able to do anything useful with Pitivi! Mathieu
I'm not sure the previous message is very clear. Let me try to make it better: bug #720699 is blocking, Pitivi generates an error at the beginning of the process and does not render anything. In my case, Pitivi does not complain (except the message above about 'gst_mini_object_unref'), renders a file, which is however useless, since it does not seem to have any video in it (although the file size would suggest so)... Hope this makes things clearer. Mathieu.
Hi Mathieu, this is a known bug afaict, can you please check if replacing every instance of 'presence="0"' with 'presence="1"' in your project file produces a correct rendered file ?
Alleluia! This works beautifully. I'm now going to test that on other projects, and on more complicated stuff... Out of curiosity, what does the "presence='0'/'1'" mean? And which bug is it, so that I can tag this bug report as a duplicate, and close it from my side? I couldn't find anything related with 'presence' in the Pitivi bugs... In the meantime, thanks a lot! I'm now able to play with Pitivi, to my great pleasure :) Mathieu.