/**
  * @param array $output_dimensions
  * @param string $image_size
  */
 public function __construct($image_size, $output_dimensions = array(), $default_image_path = '')
 {
     try {
         $utils = Anno_Keeper::retrieve('utils');
     } catch (Exception $e) {
         $utils = Anno_Keeper::keep('utils', new Anno_Template_Utils());
     }
     $this->utils = $utils;
     if (count($output_dimensions)) {
         $this->dimensions = array($output_dimensions[0], $output_dimensions[1]);
     } else {
         global $_wp_additional_image_sizes;
         $image_info = $_wp_additional_image_sizes[$image_size];
         $this->dimensions = array($image_info['width'], $image_info['height']);
     }
     $this->default_image_path = $default_image_path;
 }