curl - Strange "JPEG datastream contains no image" with PHP -

i getting remote image , checking size of it.

sometimes strange error saying jpeg datastream contains no image , narrowed down it's happening @ step, in fact it's happening @ imagecreatefromstring. problem? issue image? or need increase kind of memory setting in php.ini or..?

function ranger($url) {     $headers = array(         "range: bytes=0-32768"     );      $curl = curl_init($url);      curl_setopt($curl, curlopt_httpheader, $headers);     curl_setopt($curl, curlopt_returntransfer, 1);      $data = curl_exec($curl);      curl_close($curl);      return $data; }  $url = $prod['image1']; $raw1 = ranger($url); $im = imagecreatefromstring($raw1); $width = imagesx($im); $height = imagesy($im); 

you need follow these 3 steps solve problem:

1. as error message states, not have image. need determine why not have image. start running var_dump($raw1) take @ algorithm in general. after step should know why not have image expected one.

2. ?

3. user valid image resource parameter of imagecreatefromstring.