function __construct($config = array())
{
parent::__construct($config);
parent::set_message('numeric_positive', 'The {field} field must contain a decimal greater or equal than 0.');
parent::set_message('image_base64', 'The {field} field must be a image in base64 format.');
parent::set_message('valid_base64', 'The {field} field must be base64 data.');
}