Question

In the images folder i have a notfound.php file with

<?php
header('Content-type: image/png');
    $im = imagecreatefrompng('simnotfound.png');
    imagepng($im);
    imagedestroy($im);
    ?>

The image is a 256 by 256. The notfound.php page shows a black 256 by 256 square. The image is not all black tho. Its just some black text on a transparent background in the center.

The fix is

<?php
header('Content-type: image/png');
    $im = imagecreatefrompng('simnotfound.png');
    imagealphablending($im, true); // setting alpha blending on
    imagesavealpha($im, true); // save alphablending setting (important)
    imagepng($im);
    imagedestroy($im);
    ?>

Answer 1

create your image file one more time with white background to check that is read correctly, if yes – problem is your transparent background

also try with other file to eliminate problem with reading this specific file