I am using Kdenlive 0.9.2 on Ubuntu 10.04 LTS. Hardware is a Dell Inspiron 1420 laptop.
My project is using HD 1080p 25 fps clips in MPEG-2 M2T format (video only, no sound) which were generated in Kdenlive from historic WWI-era low-resolution clips and dubbing them with an audio file. The parameters as shown in the Render dialog when creating these clips were as follows:
f=mpegts acodec=mp2 ab=%audiobitrate+'k' ar=48000 vcodec=mpeg2video minrate=0 vb=%bitrate+'k' bf=2 b_strategy=1 trellis=1 aspect=%dar pass=%passes
Now I have reloaded these clips into a new project in order to create effects and to dub the audio. I am trying to use proxy clips due to the high resolution of the project clips, but it isn't working. After activating the "Proxy clips" option in the project settings, saving the project, then reopening, I right-click on a clip in the project tree. The context menu shows "Proxy clip" with a checkbox. The first time, right after I activated the proxy option in the project settings, there appeared a little progress bar saying something like "3 jobs" (I have three clips at the moment in the project tree). But afterwards, all is stil the same as before. In the context menu which appears when right-clicking a clip in the tree, I see "Proxy clip" and the checkbox which is always unchecked, even after I click on it. And in the Project settings, I see "0" next to "Proxy files" under the "Project files" tab.
How can I get these proxy clips to work?