Description:
------------
It's me again ;-)

I am not able to get Gmagick to read a PNG-image from an open file descriptor via Gmagick::readImageFile(), as Gmagick throws a GmagickException:

  'Improper image header ()'

The image seems to be fine however. I can save the same image to file and Gmagick will not complain with the following workaround example:

<?php
  $image = new Gmagick();
  exec("gm convert label:test png:- > /tmp/test.png");
  $image->read('/tmp/test.png');
  header('Content-type: image/' . $image->getImageFormat());
  echo $image->getImageBlob();
?>

Any way to fix the below test script or any idea for a better workaround than saving to file? OK, The file could be saved to shared memory, but I would like to avoid writing to file in general.

 - I am using gmagick-1.1.7RC3
 - Imagick works BTW



Test script:
---------------
<?php
  //$image = new Imagick(); // works
  $image = new Gmagick();
  $cmd = "gm convert label:test png:-";
  $handle = popen($cmd, 'r');
  $image->readImageFile($handle);
  header('Content-type: image/' . $image->getImageFormat());
  echo $image->getImageBlob();
?>



Expected result:
----------------
Expected: A valid PNG image.

Actual result:
--------------
Fatal error: Uncaught exception 'GmagickException' with message 'Improper image header ()' in test.php:6 Stack trace: #0 test.php(6): Gmagick->readimagefile(Resource id #2) #1 {main} thrown in test.php on line 6