Man page 1 : pbmtoascii

pbmtoascii - convert a portable bitmap into ASCII graphics

pbmtoascii [ -1x2 | -2x4 ] [ pbmfile ]

Reads a portable bitmap as input. Produces a somewhat crude ASCII graphic as output.

Note that there is no asciitopbm tool - this transformation is one-way.

The

-1x2 and

-2x4 flags give you two alternate ways for the bits to get mapped to characters. With

R 1x2 , the default, each character represents a group of 1 bit across by 2 bits down. With

R -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 - "pnmscale -width 158 | pgmnorm | pgmtopbm -thresh" should give good results.

pbm(5)

Copyright (C) 1988, 1992 by Jef Poskanzer.