http://www.perlmonks.org?node_id=492171
Description: This code snippet demonstrates how to overlay translucent text on an image using Image::Magick. It draws the text using Annotate to an overlay image with a neutral background, then uses Composite's Hardlight operation to merge the overlay image into the destination image.
use strict;
use warnings;
use Image::Magick;

my $image = Image::Magick->new ();
my $over = Image::Magick->new();

$image->ReadImage ('x.JPG');
$over->Set(size=> "1200x200");
$over->ReadImage('xc:#808080'); # Nochange colour for Hardlight
my $err = $over->Annotate
  (
  pointsize => 200,
  text => 'Hello World',
  gravity=>'center',
  stroke => '#C0C0C0', # Increase to make stroke more white
  fill => '#505050', # Decrease to make fill more black
  font => '@C:/WINDOWS/Fonts/times.TTF', # Omit for default font
  );
print $err if $err;

$image->Composite (compose=>'Hardlight', image=>$over,gravity=>'center
+');
$image->Write ('xb.jpg');