To those following this thread, team lead and fellow Yorban Lucas Beeler just pointed something illuminating out about the grey thumbnails with 'ghostlike' images - what we're actually seeing is an intermediary frame, but without its 'parent' keyframe having been read first.
As you probably already know, many common video formats store a keyframe, where all the pixels in the shot are set at once, and then, to reduce the amount of required storage space, they store what's changed between the previous frame and the current one for several frames after that; this is known as an intermediary frame (this is an oversimplification, but sufficient for this discussion). In this case, the thumbnailer has never 'seen' the keyframe, so the pixbuf it's working with is valid, but empty of anything useful (grey). The thumbnailer then applies an intermediary frame's worth of motion changes to that, leading to the ghosting. (If you ever play a low-bit-rate video in certain formats in your favourite player and drag the time slider around arbitrarily, you may see similar graphical corruption.) There is a ticket open to more-correctly use GStreamer 1.0 the way it was designed (http://redmine.yorba.org/issues/6520), and a large part of this is always seeking to a point in a video where there's guaranteed to be a keyframe. This should fix the grey thumbnail issue completely. Cheers, -c On 19/03/2013, Clint Rogers <[email protected]> wrote: > Hi again, Thomas, > > If you feel comfortable doing so, can you send one of the MP4 files > that had a grey thumbnail generated for it to [email protected]? > (It'll be treated as confidential by us, but if these contain > sensitive or private footage you'd rather not share, simply aiming the > camera that produces them at an empty wall and shooting a few seconds > of that should also work.) > > If the import was all files generated by the same camera, but only > some receive grey thumbnails, are there any other things that might be > different about them (such as resolution or file size)? > > Cheers, > -c > > On 19/03/2013, Thomas Novin <[email protected]> wrote: >> Hello >> >> Yes, I still have the problem. Some .mp4-files generates grey >> thumbnails. Just now I imported 43 files. About 25% of them where gray >> (like mosaic). All good in Nautilus as usual. >> >> $ dpkg -l | grep gstream | egrep '1.0-plugins-|plugins-bad1' >> ii gstreamer1.0-plugins-base:i386 >> 1.0.5-1~ubuntu12.10.1~ppa5 >> i386 GStreamer plugins from the "base" set >> ii gstreamer1.0-plugins-good:i386 >> 1.0.5-1ubuntu1~ubuntu12.10.1~ppa4 >> i386 GStreamer plugins from the "good" set >> ii gstreamer1.0-plugins-ugly:i386 >> 1.0.5-1~ubuntu12.10.1~ppa1 >> i386 GStreamer plugins from the "ugly" set >> ii libgstreamer-plugins-bad1.0-0:i386 >> 1.0.5-1ubuntu1~ubuntu12.10.1~ppa3 >> i386 GStreamer development files for libraries from the >> "bad" set >> >> If I remove all these imported files and do it again, the same files >> will get bad thumbnails also the next time. >> >> Rgds//Thomas >> >> >> On Mon, Mar 18, 2013 at 9:49 PM, Clint Rogers <[email protected]> wrote: >>> Hi Thomas, >>> >>> Are you still having problems with this? Please let us know. >>> >>> Also, just to reconfirm, you have the version of plugins-bad for 1.0 >>> installed already, right? >>> >>> Cheers, >>> -c >>> >>> On 12/03/2013, Thomas Novin <[email protected]> wrote: >>>> Not very good I guess, I already have "bad thumbnails" so they are not >>>> empty. >>>> >>>> https://xyz.pp.se/~thnov/up/Screenshot%20from%202013-03-12%2017:44:09.png >>>> >>>> However, I still get gray thumbnails on certain videos when I import >>>> new ones, even after the issue was closed. But still all is good in >>>> Nautilus. >>>> >>>> Rgds//Thomas >>>> >>>> On Mon, Mar 11, 2013 at 8:03 PM, Clint Rogers <[email protected]> >>>> wrote: >>>>> Hi Thomas, >>>>> >>>>> What should happen is that, if you install or update one or more >>>>> GStreamer codecs, Shotwell should pick up on this the next time it's >>>>> launched, and attempt to thumbnail any video files for which it >>>>> doesn't have thumbnails already. There shouldn't be any need to blow >>>>> away your other good thumbnails, though. >>>>> >>>>> Can you try this and let us know if it works? >>>>> >>>>> Cheers, >>>>> -c >>>>> >>>>> >>>>> On 11/03/2013, Thomas Novin <[email protected]> wrote: >>>>>> My issue is with video-files so I don't think I can do rotate there. >>>>>> >>>>>> Any other suggestion? Since I have a 20-30k+ library it seems a bit >>>>>> hefty to remove all thumbnails just to re-create 100 :) >>>>>> >>>>>> Rgds//Thomas >>>>>> >>>>>> On Sat, Mar 9, 2013 at 4:37 PM, Joseph Bylund >>>>>> <[email protected]> >>>>>> wrote: >>>>>>> Thomas, >>>>>>> I believe rotate-undo works, the original message says it does not >>>>>>> work >>>>>>> for >>>>>>> raw files. >>>>>>> http://lists.yorba.org/pipermail/shotwell/2011-November/003309.html >>>>>>> -Joe >>>>>>> >>>>>>> On 03/09/2013 07:48 AM, Thomas Novin wrote: >>>>>>>> >>>>>>>> Hello >>>>>>>> >>>>>>>> Is it possible to re-generate thumbnails for just some file(s)? I >>>>>>>> have >>>>>>>> some bad thumbnails because of Bug #6452 but I want to re-generate >>>>>>>> them when I have the fixed version of Shotwell. >>>>>>>> >>>>>>>> Rgds//Thomas >>>>>>>> _______________________________________________ >>>>>>>> Shotwell mailing list >>>>>>>> [email protected] >>>>>>>> http://lists.yorba.org/cgi-bin/mailman/listinfo/shotwell >>>>>>> >>>>>>> >>>>>> _______________________________________________ >>>>>> Shotwell mailing list >>>>>> [email protected] >>>>>> http://lists.yorba.org/cgi-bin/mailman/listinfo/shotwell >>>>>> >>>>> >>>>> >>>>> -- >>>>> --------------------------- >>>>> "I asked if Sodium, Bromine and Oxygen wanted to hang out, but they >>>>> were like 'Na Br O'..." >>>> >>> >>> >>> -- >>> --------------------------- >>> "I asked if Sodium, Bromine and Oxygen wanted to hang out, but they >>> were like 'Na Br O'..." >> > > > -- > --------------------------- > "I don't know what (b² - 4ac) equals, and I don't care," Tom said > indiscriminately. > -- --------------------------- "I don't know what (b² - 4ac) equals, and I don't care," Tom said indiscriminately. _______________________________________________ Shotwell mailing list [email protected] http://lists.yorba.org/cgi-bin/mailman/listinfo/shotwell
