I have a amd64 tripple core 3.1 ghz system with 4 GB of ram running Gentoo Linux, 64bit-compiled. I am running kdenlive-0.8, recently updated from 0.7.8 to see if it helped resolve this problem, which it didn't. My graphics chip is a radeon hd4250, if that matters.
The problem is, that when I apply even the most trivial transition, the playback speed in kdenlive gets extremely jerky (choppy, staccato, whatever), making it extremely difficult to edit anything. For example, in the current movie I'm editing, I wanted to have a couple different versions of the same clip, one at full size, and the other zoomed in on different faces. If I use the pan and zoom effect, however, the clip becomes so slow and jerky, that it is impossible to do any editing. I'm not panning here, and I'm not compositing, just simply zooming in 300%. That doesn't seem like it should be terribly mathematically challenging for the cpu. Other effects are really choppy and slow too, compositing and fading, for example.
I look at the cpu, and I see that it isn't pushed as hard as it could be. It jumps anywhere from 30% to 95% on one core, but it is not pinned at 100% or anything like it. The other two cores don't seem to be doing much at all. The memory isn't maxed-out either.
I'm wondering if there is some setting, or compile time option of some component I'm missing here that is making this so difficult. I have tried messing with all the settings on the "Settings:Configure Kdenlive" drop-down menu, but nothing seems to help. I have enabled frame-dropping on the playback as well, but it either doesn't help, or isn't enough. My computer is not a wimp... I'm sure that there must be something I can do.
Can someone please give me a hand?