int SetElValueLengthByNumber(guint32 l, guint16 group, guint16 element);
int SetElValueLengthByName (guint32 l, std::string TagName);
int SetElValueLengthByNumber(guint32 l, guint16 group, guint16 element);
int SetElValueLengthByName (guint32 l, std::string TagName);