$this->securimage->image_bg_color = new Securimage_Color(227, 218, 237);
      $this->securimage->line_color = new Securimage_Color(51, 51, 51);
      $this->securimage->num_lines = 5;
      $this->securimage->use_multi_text   = true;
      $this->securimage->multi_text_color = array(
         new Securimage_Color(184, 4, 50),
         new Securimage_Color(12, 67, 157),
         new Securimage_Color(244, 49, 11)
         );
      $this->securimage->text_color = new Securimage_Color(184, 4, 50);

<?php 
defined('C5_EXECUTE') or die("Access Denied.");
class ValidationCaptchaHelper {
   public function __construct() {
      Loader::model('system/captcha/library');
      Loader::model('system/captcha/controller');
      $captcha = SystemCaptchaLibrary::getActive();
      $this->controller = $captcha->getController();
   }      
   public function __call($nm, $args) {
      if (method_exists($this->controller, $nm)) { 
         return call_user_func_array(array($this->controller, $nm), $args);
      }
   }
}