How to disable PHP Imagick

I am using PHP Imagick package. When I call the readimage method, I get this annoying warning for some PDFs:

 **** This file had errors that were repaired or ignored.
 **** The file was produced by:
 **** >>>>  <<<<
 **** Please notify the author of the software that produced this
 **** file that it does not conform to Adobe published PDF
 **** specification.

      

        
        
        
      

    

This is all the code I am using:

$img = new Imagick();
$img->setResolution(100, 100);
$img->readimage("scan-qr.pdf[0]");
$img->setImageFormat('gif');
$img->writeImage("scan-qr-$quality.gif");
$img->clear();
$img->destroy();

      

        
        
        
      

    

Any ideas on how to turn off these warnings?