web2png.php

<?PHP 

function compute_key_for_src($src) {
  // Replace with your API key
  return md5('<YOUR API KEY>'.$src)
}

function screenshot_of($src) {
  // Replace with the url to the profile that will take the screenshot
  return 'http://www.web2png.com/s/123/frontpage.png?src=$src&key='. compute_key_for_src($src);
}     

?>

<img src="<?PHP echo(screenshot_of('http://www.cnn.com')) ?>" width="" height="" />