public function resizePortraitImage($image)
    {
        $images = array();
        $original_width = imagesx($image);
        $originl_height = imagesy($image);

        foreach ($this->_sizes as $name => $size) {
            if (!is_int($size)) {
                list($width, $height) = AnHelperImage::parseSize($size);
                if ($original_width < $width) {
                    $size = array($original_width, $originl_height);
                } else {
                    $size = array($width, 'auto');
                }
            }

            $data = AnHelperImage::resize($image, $size);
            $width = imagesx($data);
            $height = imagesy($data);
            $images[$name] = array('size' => $width.'x'.$height,'data' => $data);
        }

        if ($this->_keep_original) {
            $images['original'] = array('size' => $original_width.'x'.$originl_height, 'data' => $image);
        }

        return $images;
    }