raku-rosettacode/programming_tasks/I/Image_convolution.md

Image convolution

#!/usr/bin/env perl6
 
# Reference:
# https://github.com/azawawi/perl6-magickwand
# http://www.imagemagick.org/Usage/convolve/
 
use v6;
 
use MagickWand;
 
# A new magic wand
my $original = MagickWand.new;
 
# Read an image
$original.read("./Lenna100.jpg") or die;
 
my $o = $original.clone;
 
# using coefficients from kernel "Sobel"
# http://www.imagemagick.org/Usage/convolve/#sobel
$o.convolve( [ 1, 0, -1,
               2, 0, -2,
               1, 0, -1] );
 
$o.write("Lenna100-convoluted.jpg") or die;
 
# And cleanup on exit
LEAVE {
  $original.cleanup   if $original.defined;
  $o.cleanup if $o.defined;
}