ImageMagick uses "blobs" for converting to and from raw image data in scalars. Here are a few simple usages:

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

my $imgfile = shift;

my $image = Image::Magick->new();
$image->Read($imgfile);
my $blob = $image->ImageToBlob();
#raw image data is now in scalar $blob

#and the opposite
my $output = Image::Magick->new(magick=>'jpg');
$output->BlobToImage( $blob );
$output->Resize(geometry=>'160x120');
$output->Write('z.jpg');
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another example to show the scalar blob does indeed contain image data

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

my $image = Image::Magick->new(
   size => "600x600",
              );

$image->Read("xc:white");
$image->Draw(
   primitive => 'line',
   points    => "300,100 300,500",
   stroke    => '#600',
);

$image->Set(magick=>'gif');                                           
+         

my $blob = $image->ImageToBlob();

open(FH,"> $0.gif")or die "$!\n";
print FH $blob;
close FH;
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