Question

I have a .php file that’s supposed to load an image for display in an img tag
(i.e., <img src="the_file.php?which=0"/>). It looks like this:

<?php
    ob_clean();

    header("Content-type: image/png");

    include_once("util.php");

    //Do a simple calculation to get $name from (int)$_GET["which"];

    $im = imagecreatefrompng("protected_directory/".$name.".png");

    imagepng($im,NULL,0,NULL);

    imagedestroy($im);

    ob_end_flush();
?>

It works correctly, but the image loads substantially slower than just loading it directly
(i.e. <img src="protected_directory/the_name.png"/>, where “the_name” was calculated the same way as in the PHP file, but I can’t just do this because the protected_directory isn’t world readable).

My question is, why is this suddenly so much slower? It’s not a large image, but nor is it terribly small.

Answer 1

If you’re just displaying an existing file, use readfile() to output it to the browser. There’s no need to go through all the overhead of creating an editable GD object for this.