#!/usr/bin/perl

# pixel.cgi -- Generate a single-pixel GIF of a given color.
#
# Usage:
#  <img src="pixel.cgi/CC9966.gif" width=25 height=25>
#
# Dave W. Smith <dws@davewsmith.com>

my($rgb) = $ENV{PATH_INFO} =~ m|/([0-9A-Za-z]{6})(?:\.gif)?$|i;
$rgb ||= '888888';

my $gif = pack("H*",
               '47494638396101000100B30000' . $rgb .
               'FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF' .
               'FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF' .
               'FFFFFFFFFFFFFFFFFFFFFFFFFF2C0000' .
               '0000010001000004021044003B'
              );

binmode(STDOUT);
print "Content-type: image/gif\r\n";
print "Content-length: ", length($gif), "\r\n";
print "\r\n";
print $gif;