On Mon, 2007-02-12 at 23:50 -0800, "Germain Le Chapelain" <[EMAIL PROTECTED]> > I would like to know who to copy the alpha channel of an image to > another image.
1. Merge visible layers of the source image. 2. Copy visible layer of source image 3. Create new image for destination (as in File->New). 4. Add a layer to destination image 5. Delete background layer in destination image 6. Add black layer mask to only layer left in destination image. 7. Make black layer mask active drawable. 8. Paste into destination image. 9. Anchor to active drawable (re: mask). 10. Apply layer mask. Now the destination image (at least in that one layer) has the same alpha as your source image. Steps 4-5 could be: 4. Add alpha channel to background layer 5. (delete this step) Should also work in both 2.2 and 2.4. I tried this with a simple white image (single layer) using a gradient in a layer mask to create the source image. I then applied the layer mask in the source image to put the alpha into the layer itself. When this layer was copied to the black layer mask of the destination, the visual appearance was correct. When I saved both files (after applying the mask in the destination) they have the same file size (as expected) but they are not binary identical when saved as either XCF, TIFF or PNG. Not sure why (maybe some metadata differences?). I did notice that the pasted copy had a selection outline that was not the full size of the source image (both images where the same size). So even though I did a Select->All, Edit->Copy (I also tried Edit->Copy Visible), it appears to only have picked up to a certain transparency level in the copy. Or maybe it's just that the marching ants only recognize up to a certain level when pasted. Maybe one of the developers has some insight as to why the source and destination wouldn't be identical in this case. -- Michael J. Hammel Senior Software Engineer [EMAIL PROTECTED] http://graphics-muse.org ------------------------------------------------------------------------------ Success is never hard won. It is hard achieved. -- Michael J. Hammel _______________________________________________ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
