ppmrelief - compute a relief of a PPM image
ppmrelief
[ppmfile]
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:
<span style="font-family: monospace">
| 1 0 0 |
| 0 0 0 |
| 0 0 -1 |
</span>
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
.)
Copyright (C) 1990 by Wilson Bent (whb@hoh-2.att.com)