To parse the following code You need PHP compiled with support for the GD Graphics Library.

header("Expires Wed, 6 Sep 2000 11:11:11 GMT");
header("Last-Modified:" .gmdate("D,d M Y H:i:s")."GMT");
header("Cache-Control: no-store, no-cache, must-revalidate");  // HTTP/1.1
header("Cache-Control: post-check=0, pre-check=0", false);
header("Pragma: no-cache");                          // HTTP/1.0

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
<meta http-equiv=content-type content="text/html; charset=iso-8859-1">
<style type="text/css">
body {margin: 1em}
A:link, A:visited, A:active  {color: #cc6600; background-color: transparent; text-decoration: none}
tt {font-size: 12px; line-height: 7px}
<body bgcolor="#000000">
srand ((float) microtime() * 10000000);
$input = array ("imgs/some.png", "imgs/some1.png", "imgs/some2.png", "imgs/some3.png");
$rand_keys = array_rand ($input);

  $im = ImageCreateFromPNG($input[$rand_keys]);
  $dx = ImageSX($im);
  $dy = ImageSY($im);
  for($y=0; $y < $dy; $y++){
    for($x=0; $x < $dx; $x++){
      $col = ImageColorAt($im, $x, $y);
      $rgb = ImageColorsForIndex($im, $col);
      printf('<font color="#%02x%02x%02x">x</font>',
              $rgb['red'], $rgb['green'], $rgb['blue']);
    echo "<br>\n";
                <td width=100>&#xA0;</td>
                <td valign=bottom><a href="the_code.html">the code</a> <br><font color="#ffffff"></font></td>

Sample image 36x38 pixels

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