1994.08.26 18:00 "ppm2tiff doesn't ignored comments in the tiff-file", by Uwe Bonnes
A header in a ppm-file like:
# Ghostscript 8 bit mapped color image dump
causes ppm2tiff to abort with:
(file): Not a PPM file.
You have to erase the comment by hand. >From the definition of the ppm-file, the comment is legal.
Uwe Bonnes firstname.lastname@example.org