Calling images on website two times

Question

Hi,
When I am calling the images of the contents in the website which is developped by PHP, there is no problem to display them. But i check the Access Logs of site, Only Firefox GETs the page TWO times. Other browsers GET the page for one time, but Firefox GETs two times.
Image URL like this : http://www.mysite.com/image/name-of-the-image.jpg (With htaccess rewrite, to an image.php PHP file)
in image.php file , Image Magick (Php Image Library) prints the image..
Internet explorer, chrome, opera vs. is normal. Firefox gets two times on Access Log...
What is the solution of this problem, i couldn't find a solution...

Answer 1

Thanks David,
Yes it was a problem for development. I made the headers but still not worked. Then i tried different header, now problem solved... may be needed in the future, the correct header codes like this:
// Last Modified date for caching
$file_last_modified = filemtime($filename);
// Expires in two months
$expires = time() + (60 * 24 * 60 * 60);
header("Pragma: public");
header("Content-type: image/jpeg");
header("Expires: " . gmdate("D, d M Y H:i:s", $expires) . " GMT");
header("Last-Modified: " . gmdate("D, d M Y H:i:s", $file_last_modified) . " GMT");
Thanks