Question

i wrote this function:

function isImage($url)
  {

     $params = array('http' => array(
                  'method' => 'HEAD'
               ));
     $ctx = stream_context_create($params);
     $fp = @fopen($url, 'rb', false, $ctx);
     if (!$fp) 
        return false;  // Problem with url

    $meta = stream_get_meta_data($fp);
    if ($meta === false)
    {
        fclose($fp);
        return false;  // Problem reading data from url
    }

    $wrapper_data = $meta["wrapper_data"];
    if(is_array($wrapper_data)){
      foreach(array_keys($wrapper_data) as $hh){
          if(substr($wrapper_data[$hh], 0, 19) == "Content-Type: image") // strlen("Content-Type: image") == 19 
          {
            fclose($fp);
            return true;
          }
      }
    }

    fclose($fp);
    return false;
  }

It does checks if a url returns an image type, now i would like to extend this method controlling if returned image’s extension is in array (‘png’,’jpeg’,’jpg’).

i need this control, cause of users submitting image urls on my app.

Any suggestion will be appriciated!

Answer 1

This code snippet will return you the image type along with the checking if it’s an image :

    function get_type ($url) {

    $mimes = array (    'bmp'   =>  array('image/bmp', 'image/x-windows-bmp'),
                    'gif'   =>  'image/gif',
                    'jpeg'  =>  array('image/jpeg', 'image/pjpeg'),
                    'jpg'   =>  array('image/jpeg', 'image/pjpeg'),
                    'jpe'   =>  array('image/jpeg', 'image/pjpeg'),
                    'png'   =>  array('image/png',  'image/x-png')
            ) ;

    $info  = getimagesize($url);

    //$info['mime'] = 'image/gif';

    if ($info['mime']) {
        if ($type = array_search ($info ['mime'],$mimes)) 
            return $type;
        else {
            foreach ($mimes as $key=>$value) {
                if (is_array ($value) ) {
                    if ( !( FALSE === array_search ($info['mime'] , $value ) ))
                        return $key;
                }
            }
        }//end of else
    }
    else return "Not an image";

}

If you call this function with this :

echo get_type("http://www.gravatar.com/avatar/701467343cbd095506ca24b1ee5406d8?s=128&d=identicon&r=PG");

It will return png.

And if you call with this url :

echo get_type("http://www.google.com");

It will return Not an image.

Hope that helps . Happy coding 🙂