Description:
------------
Hello,

- PHP-5.4.3
- PECL gmagick-1.1.0RC3 (includes the attached patch)
- GraphicsMagick-1.3.13

Below is a working code with Imagick. But this doesn't work with Gmagick.


BTW:
I'm unsure where to set the ImageFormat with Gmagick. For each frame or for the complete image right before the writeImage()?

With Imagick I'm setting the the format with setFormat() one time at the beginning, after "$gmagick = new Gmagick();". But setFormat() doesn't exists in Gmagick, and setImageFormat() doesn't work at this place, becourse the image is empty at this time(--> exception empty Gmagick object).

Regards,
Carsten


Test script:
---------------
<?php
$gmagick = new Gmagick();

for ($i = 1; $i <= 3; $i++) {
    $frame = new Gmagick();
    $frame->readImage(sprintf('test%s.jpg', $i));
    $frame->setImageFormat('gif');
    $frame->setImageDelay(1000);

    $gmagick->addImage($frame);

    $frame->destroy();
}


$gmagick->writeImage('test.gif', true);

$gmagick->destroy();
?>


Expected result:
----------------
No exception.


Actual result:
--------------
[13-Jun-2012 07:48:12 UTC] PHP Fatal error:  Uncaught exception 'GmagickException' with message 'Can not process empty Gmagick object' in C:\Test\test.php:17
Stack trace:
#0 C:\Test\test.php(17): Gmagick->writeimage('test.gif', true)
#1 {main}
  thrown in C:\Test\test.php on line 17