ppmrelief - compute a relief of a PPM image

       Copyright (C) 1990 by Wilson Bent (whb@hoh-2.att.com)

       This program is part of Netpbm(1).

       ppmrelief reads a PPM image as input, and writes a relief of that image as a PPM image as output.

       The relief process is described in "Beyond Photography" by Holzmann, equation 3.19.  It's a sort of edge-
       detection and is essentially a convolution with this matrix:

           |  1  0  0 |
           |  0  0  0 |
           |  0  0 -1 |

       This manual page was generated by the Netpbm tool 'makeman' from HTML source.  The  master  documentation
       is at

              http://netpbm.sourceforge.net/doc/ppmrelief.html

netpbm documentation                             02 August 2014                         PpmreliefUserManual(1)

       ppmrelief - compute a relief of a PPM image

       There  are  no  command  line  options  defined specifically for ppmrelief, but it recognizes the options
       common to all programs based on libnetpbm (See  Common Options .)

pamshadedrelief(1), pgmbentley(1), pgmoil(1), ppm(1)

ppmrelief

       [ppmfile]