#!/usr/bin/perl
use warnings;
use strict;
use Image::Magick;

my $blob = `import -window root jpg:-`;   
#my $blob = `import -`;  #postscript produced
#print "$blob\n";

# now $blob is in memory and you can do what you
# want with it.

my $output = Image::Magick->new(magick=>'jpg');
$output->BlobToImage( $blob );
#$output->Resize(geometry=>'160x120');
$output->Write( $0.'.jpg');
# png works too

# or use Imager 
use Imager;

# Convert image 
my $img = Imager->new;
$img->read(data=>$blob, type=>'jpeg')
           or die "Cannot read: ", $img->errstr;

#See perldoc Imager::Transformations
my $rot20 = $img->rotate(degrees=>20);

$rot20->write(file=>"$0-rot20.jpg", type=>'jpeg')
           or die "Cannot write: ",$rot20->errstr;