Put a movie clip in timeline. Add color clip in timeline above movie clip. Add "composite" transition on color clip. Add "Alpha manipulation -> Rotoscoping". Kdenlive crash! It happen (without error message) with "Alpha manipulation -> Chromakey" too. I trying with .xmf and .mp4 clip, same results. Reproducible: Always Steps to Reproduce: 1. Put a movie clip in timeline. 2. Add color clip in timeline above movie clip. 3. Add "composite" transition on color clip. 4. Add "Alpha manipulation -> Rotoscoping".
Rotoscoping effect is known to crash in the Kdenlive 16.08.x versions. This was fixed in git master and will be released as Kdenlive 16.12 in december. The Chroma Key crash is something different. Can you get a backtrace ? https://userbase.kde.org/Kdenlive/Manual/BugReporting#How_to_get_useful_crash_information_.28backtrace.29
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