I have made a title clip with white letters with a transparent background in the Motion Graphic software Friction 2D and rendered it as mov with apples pro res 4444 codec which has an alpha channel. So it should be transparent.
When imported into Kdenlive the clip is solid black with white letters.
I can use an alpha shape and get it to work as a fix but it only works for two neighboring tracks and I would rather use the alpha channel in the clip so it is easy and simple to move it around the timeline.
What do I have to do to “activate” the alpha channel so to speak. Reading the manual I kind of thought Kdenlive automatically uses an alpha channel.
I am on Linux Mint 21.3 with the latest Kdenlive appimage.
Hmmmm. I think the problem is with Friction 2D (or my use of Friction 2D) and not with KDenlive (or my use of it) because testing a PNG with transparency made in Inkscape did work as expected out of the box. I am guessing that Friction 2D simply cant render mov with an alpha channel even if you choose quicktime mov pro res 4444 codec because the colour format is restrictet to YUVxxxxx and looking at videos for After Effects it should apparently be RGB+alpha.
My mistake…
Well Friction 2D can make mov pro res 4444 videos with an alpha channel. Using not rgb+alpha but yuva444 and the transparency shows up in mpv player fine. So I did use Friction 2D incorrectly. Now here is the problem. Kdenlive does automatically find the alpha channel of a PNG with transparency. But it still does not find the alpha channel of my new mov pro res 4444 yuva444 even though it has one as shown by the mpv player. So what am I doing wrong or not doing to make it work for videos…
Well I think I have a work around. If I place a PNG with transparency (nothing else) on a track above the clip with the alpha channel magic happens and the transparency works for the video as well. Fun and games…but it works