public function initializeArguments()
{
parent::initializeArguments();
$this->registerUniversalTagAttributes();
$this->registerArgument('width', 'integer', 'Width of rendered placeholder image', false, 640);
$this->registerArgument('height', 'integer', 'Height of rendered placeholder image', false, false);
$this->registerArgument('backgroundColor', 'string', 'Background color', false, '333333');
$this->registerArgument('textColor', 'string', 'Text color', false, 'FFFFFF');
}