rawtopgm(1) on Linux
The text 511d076191f4, as Debian 2.2 (Potato), Debian 2.1 (Slink), Debian 2.0 (Hamm) shipped it.
convert raw grayscale bytes into a portable graymap
Flags it lists
-
-headerskip -
-rowskip -
-tb -
-topbottom