/// <exception cref="XmpException"/>
        private static void ProcessXmpDateTag([NotNull] IXmpMeta meta, [NotNull] XmpDirectory directory, int tagType)
        {
            string schemaNs;
            string propName;

            if (!XmpDirectory.TagSchemaMap.TryGetValue(tagType, out schemaNs) || !XmpDirectory.TagPropNameMap.TryGetValue(tagType, out propName))
            {
                return;
            }

            var cal = meta.GetPropertyCalendar(schemaNs, propName);

            if (cal != null)
            {
                directory.Set(tagType, cal.GetTime());
            }
        }