pbmtoascii - convert a portable bitmap into ASCII graphics
Reads a portable bitmap as input. Produces a somewhat crude
ASCII graphic as output.
Note that there is no asciitopbm tool - this transformation
The -1x2 and -2x4 flags give you two alternate
ways for the bits to get mapped to characters. With
1x2, the default, each character represents a group
of 1 bit across by 2 bits down. With -2x4, each
character represents 2 bits across by 4 bits down. With the
1x2 mode you can see the individual bits, so it's useful for
previewing small bitmaps on a non-graphics terminal. The 2x4
mode lets you display larger bitmaps on a standard 80-column
display, but it obscures bit-level details. 2x4 mode is also
good for displaying graymaps -
Copyright (C) 1988, 1992 by Jef Poskanzer.