$re = '/<img src=\".+?\/PIAimages\/(.+)\"/i';
$str = '<img src="www.ikea.com/ms/img/header/logo.gif" >
<img src="www.ikea.com/ms/ru_RU/img/ads/askanna.jpg" >
<img src="www.ikea.com/ms/img/header/main_menu_shadow.gif" >
<img src="www.ikea.com/ms/media/seorange/20153/20151_dica04a..." >
<img src="www.ikea.com/PIAimages/0322782_PE516321_S3.JPG" >
<img src="www.ikea.com/PIAimages/0355650_PE547817_S3.JPG" >
www.ikea.com/PIAimages/0292760_PE425390_S3.JPG" >
www.ikea.com/PIAimages/0325067_PE523174_S3.JPG" >';
preg_match_all($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