<?php  $pdf_file   = './pdf/demo.pdf';  $save_to    = './jpg/demo.jpg';     //make sure that apache has permissions to write in this folder! (common problem)  //execute ImageMagick command 'convert' and convert PDF to JPG with applied settings  exec('convert "'.$pdf_file.'" -colorspace RGB -resize 800 "'.$save_to.'"', $output, $return_var);  if($return_var == 0) {              //if exec successfuly converted pdf to jpg      print "Conversion OK";  }  else print "Conversion failed.<br />".$output;  ?>