刚刚在文档中找到它： http://docs.magentocommerce.com/Mage_Catalog/Mage_Catalog_Helper_Image.html

Just found it in the docs: http://docs.magentocommerce.com/Mage_Catalog/Mage_Catalog_Helper_Image.html

似乎是：

$this->helper('catalog/image')->init($_product, 'image')->getOriginalHeight()
$this->helper('catalog/image')->init($_product, 'image')->getOriginalWidth()