PHP check image if exists and return a text if not

Question

I found this solution, because @getimagesize was horrible slow:

function get_image_by_id($ID)
{
$url = $ID;
$ch = curl_init($url);
curl_setopt($ch, CURLOPT_HEADER, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_exec($ch);
$info = curl_getinfo($ch);
if(file_get_contents($url) == NULL)
{
    return NULL;
}
else
{
    return $url;
}
}

It works very fast but this function always tries to load the image even if it isn't exists. Here is how I implement into my code:

<?php if (get_image_by_id($link)): ?>
    <?php echo '<img src="' . $link . '" alt="' . $propname . '" />'; ?>
<?php endif; ?>

I need an else only if the image isn't exists then only echo $propname from the array.

With is_null it works but it has the same speed as @getimagesize (slow).

So now the else looks like:

<?php if (is_null(get_image_by_id($link))): ?>
    <?php echo $propname; ?>
<?php endif; ?>

How can I make a fast code to this:

if(image_exists($link) {
echo $image;
} else {
echo $propname;
}

Answer 1

Use Curl for returning status to identify existence of image

<?php
    function image_exist($url){
        $ch = curl_init($url);    
        curl_setopt($ch, CURLOPT_NOBODY, true);
        curl_exec($ch);
        $code = curl_getinfo($ch, CURLINFO_HTTP_CODE);

        if($code == 200){
           $status = true;
        }else{
          $status = false;
        }
        curl_close($ch);
       return $status;
    }
    ?>

Answer 2

You can test to see the curl response and if you have something then do your code:

$output=curl_exec($ch);
if ($output === false || $info['http_code'] != 200) {
  //$output = "No cURL data returned for $url [". $info['http_code']. "]";
  //if (curl_error($ch))
  //  $output .= "\n". curl_error($ch);
  //}
  return null; //or $output
else {
  // 'OK' status; format $output data if necessary here: 
  return $url;
}

don't forget to close the curl connection curl_close($ch);