#!/usr/bin/perl
use warnings;
use strict;
use Imager;

my $factor = 1.5; #  above 1 will lighten, 
                #  between 0 and 1 it with darken

my $file = shift or die "Need a file $!\n";

my $newtype = 'jpg';

( my $basename) = $file  =~ /(.*)\.(\w+)$/;

my $img = Imager->new();
$img->open(file=>$file) or die $img->errstr();

my $newimg = $img->copy();

my @map = map {  int( $factor * $_)  } 0..255;

$newimg->map(all=> \@map);

my $newname = $basename.'-light'.'.jpg';
print "$newname\n";

$newimg->write(file =>  $newname );
