use strict;
use warnings;

use Imager;
use Imager::Filter::Autocrop;

my $imgdata = undef;
open(IN, '<', 'example.jpg');
binmode(IN);
{ local $/ = undef; $imgdata = <IN> }
close(IN);

my $img = Imager->new();
# possible params are 'file', 'data' and 'fd'
$img->read(data=>\$imgdata) or die "read: ".$img->errstr();

$img->filter(type=>'autocrop', fuzz=>20) or die "autocrop: ".$img->errstr();
$img->write(file=>'out.jpg') or die "writing: ".$img->errstr();