handle image URL (.htaccess) by passed variable - apache

Question

I would like to handle my image URLs in two different ways.
First, when the browser calls for:
http://example.com/image.jpg (need to be shown)
Second, when the browser calls for:
http://example.org/image.jpg?actionId=123 (need to be URL rewrote to index.php?actionId=123)
The point is, when the URL has it's specified variable, then we need to redirected to the index.php with that variable and it's value.
I'm using .htaccess with mod_rewrite, which is the following now:
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php?q=$1 [QSA]
</IfModule>
So it's checks for existing file or directory, any other way, it's passed to index.php in 'q' param.
Thank you in advance!

Answer 1

For the first example you don't need to do anything, the image will be shown if it exists. Therefore you only need to consider the case with the query string:
RewriteEngine On
RewriteCond %{QUERY_STRING} actionId=([^&]+)
RewriteRule \.jpg$ index.php?actionId=%1 [L]
If there are other parameters that you also need to pass to to index.php then just doing the rewrite should be enough as the query string is sent by default. To be sure use the QSA flag:
RewriteEngine On
RewriteCond %{QUERY_STRING} actionId=([^&]+)
RewriteRule \.jpg$ index.php [QSA,L]