protected function setImageStyle($style_id)
    {
        $this->data_imagestyle = array();

        if (is_numeric($style_id)) {

            $this->data_imagestyle = $this->image_style->get($style_id);

            if (empty($this->data_imagestyle)) {
                $this->outputHttpStatus(404);
            }
        }

        $this->prepareImageStyle($this->data_imagestyle);
    }