I have a php script which create a dynamic image with cache. I use ETAG and expire headers for all my images, for this I use a regexp like '.(jpg|gif|png)$'.
With this method a user receive a "304 Not Modified" server response when the user has in cache images from my website and he refreh a page.
The problem is that my dynamic image are cached by the brower but if the user refresh the page he receive a "200 ok" status and not a "304 Not Modified" status. (I'm working on local and the time response of my local server is varying from 125ms to 375ms only for getting a image, I really need to have 304 status)
What can I do for having a "304 Not Modified" status for dynamic images?
Thanks in advance.