RewriteEngine on
Options All -Indexes

RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !^http://ronkssystems.com/.*$      [NC]
RewriteCond %{HTTP_REFERER} !^http://ronkssystems.com$      [NC]
RewriteCond %{HTTP_REFERER} !^http://www.ronkssystems.com/.*$      [NC]
RewriteCond %{HTTP_REFERER} !^http://www.ronkssystems.com$      [NC]
RewriteCond %{HTTP_REFERER} !^http://ddytalk.com/.*$      [NC]
RewriteCond %{HTTP_REFERER} !^http://ddytalk.com$      [NC]
RewriteCond %{HTTP_REFERER} !^http://www.ddytalk.com/.*$      [NC]
RewriteCond %{HTTP_REFERER} !^http://www.ddytalk.com$      [NC]
RewriteCond %{HTTP_REFERER} !^http://ddytalk.ca/.*$      [NC]
RewriteCond %{HTTP_REFERER} !^http://ddytalk.ca$      [NC]
RewriteCond %{HTTP_REFERER} !^http://www.ddytalk.ca/.*$      [NC]
RewriteCond %{HTTP_REFERER} !^http://www.ddytalk.ca$      [NC]
RewriteRule .*\.(jpg|jpeg|gif|png|bmp)$ - [F,NC]