Generate a transition between two PPM images. More information: https://netpbm.sourceforge.net/doc/ppmfade.html.
ppmfade -f path/to/image1.ppm -l path/to/image2.ppm -mix|spread|shift|relief|oil|...
ppmfade -f path/to/image.ppm -mix|spread|shift|relief|oil|...
ppmfade -l path/to/image.ppm -mix|spread|shift|relief|oil|...
base.NNNN.ppm
where NNNN
is a increasing number:ppmfade -f path/to/image1.ppm -l path/to/image2.ppm -mix|spread|shift|relief|oil|... -base base