#!/usr/bin/env perl
use strict;
use warnings;
use feature 'say';
use Data::Printer;
use Image::ExifTool qw(:Public);

my $image = $ARGV[0];

my $exif = ImageInfo( $image, 'XResolution', 'YResolution' );
p $exif;

my $xrez = $$exif{'XResolution'};
my $yrez = $$exif{'YResolution'};

say "Resolution is $xrez x $yrez.";
__END__
\ {
    XResolution   180,
    YResolution   180
}
Resolution is 180 x 180.