small fix for embeded url

app/models/ad_image.rb

@@ -36,7 +36,7 @@ class AdImage
 
   def embed_url
     uri = URI.parse(self.youtube) rescue nil
-    if !uri.nil?
+    if !uri.nil? && uri.host == "www.youtube.com"
       params = CGI.parse(uri.query)
       v = params['v'].first
       return "http://www.youtube.com/embed/#{v}"