Sorry for the long post, but I fear I cannot describe it shorter :)
I am running kdenlive 0.9.5-git20130403 on a 64bit ubuntu 12.04, AMD quadcore @ 2.7 Ghz and 8GB of RAM.
In my current project I use stills ( 8MP up to 18MP ) and movie clips (1080p and 1080i) to create a movie of my last trip to new zealand. I have appx. 1000 stills and 250 movie clips to be added to the final edit. The project setting is for output to 1080p @ 25fps.
With this setup I have several problems:
1.) I have now added ~200 stills/movie clips and kdenlive will constantly use up my memory after a while of editing ( > 5.6 GB after 1 hr work) which will cause the system to swap once I start rendering out ( melt using up to 3 GB) in my current setting. Also the loading time for the project is already very long. I am forced to split the project into several sub projects and do a final edit from the parts, which is not really very convenient.
Are there any tips on how to tackle this problem ?
2.) This is the one which bothers me most: When working with the setting of 1080p@25fps the playback is slow. For the clips and stills alone without any effects it is at ~ 15fps but as soon as transistions and effects ( most notably pan and zoom) are used the frame rate drops to 1-3 fps and sometimes even below that. Even with the realtime setting checked I do not get any usable feedback about the timing and needed editing of the movie. It is mostly guesswork and the turnaorund cycles via rendering are very long.
If I reduce the project settings to 1/4 (480x270@25fps) I manage to get a realtime display almost throughout the project. Working with this setting helps tremendously.
Now the problem is, that I cannot simply switch the project back to 1080p, as all the effects with transformations or cropping are using absolute values, thus ruining all my hard work in setting up the correct transformations (still image clipping, Ken-Burns Effects etc).
I tried all sorts of approaches but never got any settings which gave me a fast playback and a FullHD output.
Right now I have hacked together a dirty program which adjusts the effect settings to the proper values for either the 1080p or the 1/4 settings. This works astongishly well, but directly manipulating the .kdenlive project files is not a good way to deal with this.
Have I overlooked something obvious or is there no support from kdenlive to edit in a low resolution and render it out in a high one ?
Any thoughts and ideas are highly appreciated.