const gchar *exif_item_get_format_name(ExifItem *item, gint brief);
gchar *exif_item_get_data_as_text(ExifItem *item);
gint exif_item_get_integer(ExifItem *item, gint *value);
-ExifRational *exif_item_get_rational(ExifItem *item, gint *sign);
+ExifRational *exif_item_get_rational(ExifItem *item, gint *sign, gint n);
gchar *exif_item_get_string(ExifItem *item, gint idx);