$re = '/((\[IMG WIDTH\=[\d]+ HEIGHT\=[\d]+])(.*)(\[\/IMG\]))/';
$str = '[IMG WIDTH=604 HEIGHT=467]http://img1.joyreactor.cc/pics/post/%D0%BA%D0%BE%D1%82%D0%B8%D0%BA%D0%B8-%D0%B6%D0%B8%D0%B2%D0%BD%D0%BE%D1%81%D1%82%D1%8C-%D0%B4%D0%BB%D0%B8%D0%BD%D0%BD%D0%BE%D0%BF%D0%BE%D1%81%D1%82-%D0%BF%D0%B5%D1%81%D0%BE%D1%87%D0%BD%D0%B8%D1%86%D0%B0-1170505.jpeg[/IMG][IMG WIDTH=604 HEIGHT=467]http://img1.joyreactor.cc/pics/post/%D0%BA%D0%BE%D1%82%D0%B8%D0%BA%D0%B8-%D0%B6%D0%B8%D0%B2%D0%BD%D0%BE%D1%81%D1%82%D1%8C-%D0%B4%D0%BB%D0%B8%D0%BD%D0%BD%D0%BE%D0%BF%D0%BE%D1%81%D1%82-%D0%BF%D0%B5%D1%81%D0%BE%D1%87%D0%BD%D0%B8%D1%86%D0%B0-1170505.jpeg[/IMG]';
preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0);
// Print the entire match result
var_dump($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