capturar pantalla PHP

<?php
function getScreenShot($url, $width)
{
$path = "http://s.wordpress.com/mshots/v1/";
return $path.urlencode($url)."?w=".$width;
}
?>

<img alt="" src="<?echo getScreenShot('http://www.vidadelprogramador.com', 300);?>" />




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