modify Images.php use regex to php function

@@ -67,7 +67,7 @@ class Helpers
      */
     public static function getFilterUrl($url)
     {
-        $url = strtr($url, array('.m.yohobuy.com' => SUB_DOMAIN, OLD_MAIN => SITE_MAIN));
+        $url = strtr($url, array('.m.yohobuy.com' => SUB_DOMAIN, OLD_MAIN => SITE_MAIN, 'www.yohobuy.com' => SITE_MAIN));
         $filter = strstr($url, 'openby:yohobuy=', true);
         if ($filter) {
             return rtrim(rtrim($filter, '?'), '&');

@@ -48,7 +48,7 @@ class Images
      */
     public static function getSourceUrl($fileName, $bucket = 'yhfair')
     {
-        if(preg_match('|http://|', $fileName)){
+        if(stripos($fileName, 'http://') === 0){
             return $fileName;
         }
         $domain = self::getDomain($bucket, $fileName);