Copy content of channels into other ones

[top1r]

Hi, I would like to know how to copy the content of colors channels RGB (Red, Green and Blue) into Green, then copy the content of Alpha channel into Red ?

I tried it on PS and it was quite easy, but I can't manage to reproduce it on Gimp.

Thanks and have a good day !

[rich2005]

Try:
Colors -> Components -> Decompose ...choose RGBA and to layers
that makes a new image.
Copy the Alpha layer Edit -> Copy
Go to the Red layer and Edit -> Paste As -> Paste As Floating Data
Anchor that "Floating layer"  Either in Layer dock or Layer -> Anchor floating Layer or Mask
Colors -> Components -> Recompose
Go back to the original image for the change.

A 40 second animation of that:  https://sendvid.com/esy5aj3v