How to prevent a file from direct URL Access using htaccess

RewriteEngine on 
RewriteCond %{HTTP_REFERER} !^http://(www\.)?localhost [NC] 
RewriteCond %{HTTP_REFERER} !^http://(www\.)?localhost.*$ [NC] 
RewriteRule \.(gif|jpg)$ - [F]

Thanks to https://stackoverflow.com/questions/10236717/how-to-prevent-a-file-from-direct-url-access