# ImgSum.pm
package ImgSum;

use strict;
use warnings;

use Image::Magick;

sub summary {
    my ($imgf, $res) = @_;
    my $img = new Image::Magick;
    $img->Read($imgf);

    my ($w, $h) = $img->Get(qw/rows columns/);

    my @sum;
    my $i = 0;
    for (my $y = 0; $y < $h; $y += $res)
    {
        for (my $x = 0; $x < $w; $x += $res)
        {
            my $px = $img->Get("pixel[$x,$y]");
            my $rgb = [split/,/, $px];
            $sum[$i++] = $rgb;
        }
    }
    return \@sum;
}

1;