In some cases, chroma key works horribly and color selection works very well. I was editing michael rosen ytps and since michael rosen has two backgrounds, I wanted to use color selection twice. Why does kdenlive let you use chroma key twice and not color selection?

If this is a unsolvable issue how can I flag it up as a issue that kdenlive devs should fix for the next update?

Yo're rright bluescreen & color selection together seem to work. I first did not notice that only the last one takes effect if two color sel.

See my mixed test results on gallery or http://youtu.be/gZ6a71feK7E

but for what I am doing chroma key/bluescreen cuts out the shirt. I NEED TO BE ABLE TO USE COLOR SELECTION TWICE (It works). How can I do this?

Perhaps I don't undestand your problem, but: Bluescreen color does not have to be blue or green. Use variance. First color selection, then bluescreen works. Or perhaps encode first selection and then use color selection again. If background image has same colors than the person, it's difficult anyway. Perhaps rotoscoping...

Yes, I can use bluescreen after color selection, BUT the quality of the bluescreen effect is poor on michael rosen videos.
https://imgur.com/a/rotAg
That was a comparision between color selection and chroma key. However, I cannot use color selection twice and have to ruin my video with chroma key

The real problem is the background with same color than the hair. You can use color selection multiple times if using e.g. lossless rendering. But that grey background & same color hair! Perhaps easier with original footage. Lossless renderings are huge. First color selection & then keyframe & moving rotoscoping. Laborious!

You can use the color selection as many times as you want, building a combined mask, just select the appropriate operation.
By default it is "write on clear", which will of course overwrite any previous alpha.


https://userbase.kde.org/Kdenlive/Manua ... nipulation

https://userbase.kde.org/Kdenlive/Manua ... n_Category

THANK YOU SO MUCH!!!!

The "min" operation worked and now I can use 2 color selections. What does "max" and "add" do? In my experience it just stopped the chroma keying from happening

The "operation" determines how the alpha generated in the last step will combine with the alpha from previous steps.
"Alpha" is the opacity, so "min" will combine the transparent parts, "max" will combine the opaque parts, etc.
Put another way, "min" is like a OR function for transparency - the output will be transparent where either of the two masks is transparent.
"Max" is a AND function for transparency (OR function for opacity), so if you have two non-overlaping transparent areas, nothing will be transparent after the "max" operation.

Why isn't min set by default???