RewriteEngine On
RewriteCond %{QUERY_STRING}	^.*(w|h|f)\=.*$
RewriteRule ^(wp\-content\/uploads\/.*\.)(jpg|JPG|jpeg|png|PNG|gif|GIF)$ /thumb.php?image=$1$2 [QSA,L]

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress