![Documentation-Of-Coinfinds-I.-Photography-Supplement]()
Gimp 2.8 creates an alpha channel as a single layer during the automatic process of editing the images to remove the background. Because not all viewers and image manipulation programs support the alpha channel, it is necessary to combine the layers. Flattening the image layers for single and batch files is described in the booklet.
It is written in german but with a lot of sreenshots.
Free download
https://niedersachsen.academia.edu/...chWerz/BooksEnjoy
Uli
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