#!/usr/bin/perl -wT
use strict;

# types where extension <> content-type
my %types = qw(jpg jpeg tif tiff);

# get an array of image-files
my @images = glob("./images/*");
die "No images found\n" unless scalar @images;

# choose an image and and prepare content type extension
my $image = $images[int(rand @images)];
die "No extension for $image\n" unless $image =~ /\.(.+)$/;
my $ctype = $1;
$ctype = $types{$ctype} if exists $types{$ctype};

# read and  print image
open(IMG, $image)||die "Cannot open $image:$!\n";
print "Content-type: image/$ctype\n\n";
binmode (IMG);
binmode (STDOUT);
print while(<IMG>);
close IMG;