I 'm locking for a function to downgrade an image from 32bit per channell to 8 bit per channell.
I searched in the help menue and in the full list of functions ( from script-Fu Consol). I did not found any function to use for this one. The function image-convert-rgb is contained only in the libgimp-2.0-0.dll. This means I do not know how to extend this function for implementing the color depth changes.
Does somebody know how to do do it in Gimp without going to e.g. Photoshop or irfanview.
The higher pixel depth is realy usefulle if you do many curve manipulations with scanned images. I avoid many gaps in the histogram comming from integer calculations & limits here.
The opposite function (upgrade from 8 to e.g. 32bit/channel) will be required in the future.