title: set compression headers and compress , caching headers?
body: <p>What headers should a send with an image output (image.php when opened allows user to download an image) to set caching time for that image to 3 days (instead of re-downloading the image from the user side) ??</p>
  
  <p>and how can i compress the image and send it compressed and what headers should i send along to tell the browser that this image is compressed ?</p>
  
  <p>thank you .</p>