Kdenlive/Manual/Effects/Alpha manipulation/Rotoscoping
Rotoscoping
"In the visual effects industry, the term rotoscoping refers to the technique of manually creating a matte for an element on a live-action plate so it may be composited over another background." Wikipedia
Examples of what you can do with the Rotoscoping effect.
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see also Rotoscoping on ttill's blog
This video is about green screen on Kdenlive but he does use rotoscoping in it too.
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