그림파일의 평균RGB 값 구하기

average-color.pl

#!/usr/bin/env perl

use strict;
use warnings;

use GD;

my $img = GD::Image->new($ARGV[0]);

my ($width, $height) = $img->getBounds;

my $n = 0;
my $avg = 0;

for my $y (0 .. $height - 1) {
    for my $x (0 .. $width - 1) {
        my ($r, $g, $b) = $img->rgb( $img->getPixel($x, $y));
        my $rgb =  ($r << 16) + ($g << 8) + $b;
        $avg = ($n * $avg + $rgb) / ($n + 1);
        $n += 1;
    }
}
printf "#%06X\n", $avg;

=pod

Usage:
  
  perl average-color.pl [file]
  
=cut