This is the command pgmedge that can be run in the OnWorks free hosting provider using one of our multiple free online workstations such as Ubuntu Online, Fedora Online, Windows online emulator or MAC OS online emulator
PROGRAM:
NAME
pgmedge - edge-detect a portable graymap
SYNOPSIS
pgmedge [pgmfile]
DESCRIPTION
Reads a portable graymap as input. Outlines the edges, and writes a portable graymap as
output. Piping the result through pgmtopbm -threshold and playing with the threshold
value will give a bitmap of the edges.
The edge detection technique used is to take the Pythagorean sum of two Sobel gradient
operators at 90 degrees to each other. For more details see "Digital Image Processing" by
Gonzalez and Wintz, chapter 7.
The maxval of the output is the same as the maxval of the input The effect is better with
larger maxvals, so you may want to increase the maxval of the input by running it through
pnmdepth first.
Use pgmedge online using onworks.net services