$re = '/(?:http:\/\/)(.*?)\/(.+?)(?:\/|\?|\#|$|\n)\w*.jpg/';
$str = '<div style="padding-right: 16px;"> <img class="img-thumbnail gamedetailthumb" src="http://images.cdn.spilcloud.com/thumbs-1-5/200X120_162615.jpg"> <img class="img-thumbnail gamedetailthumb" src="http://images.cdn.spilcloud.com/thumbs-1-5/120X90_162615.jpg"> <img class="img-thumbnail gamedetailthumb" src="http://images.cdn.spilcloud.com/thumbs-1-5/100X75_162615.jpg"> </div>';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php