Hi everybody. I am new to Linux. My distro is Elementary OS 0.3 (Freya) which is basically based on Ubuntu 14.04. When i first installed Kdenlive (0.9.6) fresh, it did great job with my Apple Prores 4K 4444 files. I even did some color grading and denoising (frei0r plugins were working) and all. It was actually much faster than i expected. Then after I installed 0.9.10 and got a segmentation error. It wasn't opening at all. It took me a few hours to discover to move the mlt directory from usr/lib to usr/local/lib and i got it firing up again. Now it opens up fine however not only Prores 4K 4444 but whatever clip that i could have found including some very simple avi ones won't import to my project and the "Clip is invalid will be removed from project" warning pops up.

I can still watch the Prores 4K 4444 .mov files in Audience (eOS video player) and in VLC (much slower but yes). I removed VLC by thinking some vlc libs might be getting into Kdenlive's way but no change.

ii kdenlive 0.9.10-0ubuntu0~sunab~trusty1 amd64
ii kdenlive-data 0.9.10-0ubuntu0~sunab~trusty1 all
ii kdenlive-dbg 0.9.10-0ubuntu0~sunab~trusty1 amd64

ii frei0r-plugins 1.4.0+git20140826.72e51041-0ubuntu0~sunab~trusty1 amd64

ii chromium-codecs-ffmpeg-extra 43.0.2357.130-0ubuntu0.14.04.1.1092 amd64
ii ffmpeg 7:2.7.2+git~trusty amd64
ii gstreamer0.10-ffmpeg:amd64 0.10.13-5ubuntu1~trusty2 amd64
ii libffmpegthumbnailer4 2.0.8-2 amd64
ii libxine2-ffmpeg 1.2.4-2ubuntu1 amd64

ii libmlt++3 0.9.3+git20141005.22abed67-0ubuntu0~sunab~trusty1 amd64
ii libmlt-data 0.9.3+git20141005.22abed67-0ubuntu0~sunab~trusty1 all
ii libmlt6 0.9.3+git20141005.22abed67-0ubuntu0~sunab~trusty1 amd64

added repositories are
http://ppa.launchpad.net/sunab/kdenlive-release/ubuntu trusty main
http://ppa.launchpad.net/mc3man/trusty-media/ubuntu trusty main

helps appreciated.

Just for a record. I fixed it.

I have discovered some residual libmlt* files under /usr/lib those were incompatible with the currently installed 0.9.3+git20141005.22abed67 version. They belonged to a higher version (i guess 0.9.6 or something) which i had built from source. I removed melt with sudo apt-get remove melt --purge and then deleted all existing mlt* and libmlt* files along with directories named mlt under usr/lib and usr/local/lib. After a fresh install of melt 0.9.3+git20141005.22abed67 and fixing the Kdenlive Settings to point at the right directories for ffmpeg, ffmplay and melt solved it.

Then somebody had to stop me but i was all alone and I have even managed to fire up all my 6 cores for h264 rendering which cut the rendering time by 4 . But that's another story.