$re = '/((?:https?(?:%3A%2F%2F|:\/\/))(?:www\.)?(?:\S+)(?:%2F|\/)(?:(?!\.(?:mp4|mkv|wmv|m4v|mov|avi|flv|webm|flac|mka|m4a|aac|ogg))[^\/])*\.(mp4|mkv|wmv|m4v|mov|avi|flv|webm|flac|mka|m4a|aac|ogg))(?!\/|\.[a-z]{1,3})/im';
$str = 'http://test.com/test.mkv
http://test.com/test/test.jpg.mkv
https://test.com/test.mkv?test=test
http%3A%2F%2Ftest.com%2Ftest.mkv%3Ftest%3Dtest
https%3A%2F%2Ftest.com%2Ftest.jpg.mkv%3Ftest%3Dtest.mkv
http://test.com/t est.mkv__some__random__string__http://test.com/test.mkv
The last example should match the two URLs but, not the __some__random__string__.
Some examples that should not be matched:
http://test.com/test.mkv.jpg
http://test.com/test.mkv/test.jpg
https://test.com/test.mkv.jpg?test=test.mkv
http%3A%2F%2Ftest.com%2Ftest.mkv.jpg
https%3A%2F%2Ftest.com%2Ftest.mkv.jpg%3Ftest%3Dtest.mkv
http://test.com/t est.mkv__some__random__string__http://test.com/test.mkv.jpg
The last example should match only the first URL, before __some__random__string__';
preg_match_all($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