语法无效 - 旋转木马的Glob图像目录扫描

I have the following syntax error with this code:

Warning: natcasesort() expects parameter 1 to be array, boolean given in Website/assets/country-gallery-js.php on line 14

Warning: Invalid argument supplied for foreach() in Website/assets/country-gallery-js.php on line 15

    <?php $thumbs = glob("img/thumb/*.{jpg,png,gif}", GLOB_BRACE); ?>
    <?php
    if(count($thumbs)) {
      natcasesort($thumbs);
      foreach($thumbs as $thumb) {?>
            <li class="item">
              <a class="fancybox" rel="gallery1" href="img/large/<?php echo basename($thumb) ?>">
                  <img src="<?php echo $thumb ?>" class="img-circle" width="100%" alt="" />
              </a>
          </li>
        <?php
        }
    }
    else {
      echo "Sorry, no images to display!";
    }
    ?>

I am unsure as to why. The code scans a folder for images to display as a carousel. It scans a thumbnail and large image folder for lightbox. When images are in the folder, it works like a treat.. when the folder is empty it should echo the 'else' text code. Instead it displays this syntax.

Can anyone help me figure this one out and stop the syntax from appearing?

Use is_array instead of count 
<?php $thumbs = glob("img/thumb/*.{jpg,png,gif}", GLOB_BRACE); ?>
<?php
if (is_array($thumbs)) {
    natcasesort($thumbs);
    foreach ($thumbs as $thumb) {
        ?>
        <li class="item">
            <a class="fancybox" rel="gallery1" href="img/large/<?php echo basename($thumb) ?>">
                <img src="<?php echo $thumb ?>" class="img-circle" width="100%" alt="" />
            </a>
        </li>

        <?php
    }
} else {
    echo "Sorry, no images to display!";
}
?>

I believe using the braces syntax:

glob("img/thumb/*.{jpg,png,gif}", GLOB_BRACE);

wont work, this probably will:

glob("img/thumb/*.jpg,img/thumb/*.png,img/thumb/*.gif", GLOB_BRACE);

The first step to what you ought to do to check where the problem lies is check what kind of value the variable $thumbs holds. This would have told you that the problem probably lies within the glob function.