Firstly I am blown away by how far Kdenlive has come after being away from it for over a year! I develop AV Linux which is an LXDE based Debian Multimedia Content Creation distro which features the well known gtk based Linux NLEs LiVES and Openshot as well as Cinelerra. I originally included Kdenlive but it was difficult to integrate into LXDE without font display issues not to mention the added bulk of the KDE4 support libs. Recently I did an experiment with a KDE4 based AV Linux and finally got re-acquainted with Kdenlive and am very impressed with 0.7.8.
One issue I've encountered is trying to get profiles to use all the threads for rendering on a quad core machine, Handbrake and WinFF will use all the cores but not Kdenlive. I have created a custom x264 profile for my iPod and passing the 'threads=0' or 'threads=4' command doesn't seem to make any difference to the encoding speed even if I use existing Kdenlive x264 profiles. I am using mlt 0.5.10, ffmpeg 0.6SVN-r24504 and libx264-104 on Debian Squeeze.
Here is the profile:
s=640x480 aspect=%dar progressive=1 threads=4 acodec=aac ab=128k vcodec=libx264 crf=21 flags=+loop cmp=+chroma partitions=+parti8x8+parti4x4+partp8x8+partb8x8 me_method=umh subq=5 me_range=16 g=250 keyint_min=25 sc_threshold=40 i_qfactor=0.71 qcomp=0.6 directpred=1 trellis=1 coder=0 bf=0 refs=1 flags2=-wpred-dct8x8 level=13 bufsize=768k wpredp=0 bt=256k
Any help would be appreciated...