How to replace the field type and value in dbgrid?

How to replace the field type and value in dbgrid?

My SQL query:

Code: XML [Select] DBForm.DBquery.SQL.text:='select callstart, callend, origin, destination, direction from callrecord;

termtype are integer values 0...3, instead I would like to show in dbgrid column fields: None, Incoming, Outgoing or Internal, accordingly. These text values are not stored in any DB table to be joined with; it is also not allowed to add smth to this DB (in my case). Is there a way how to do this "on fly", when the dbgrid obtains the values from the DB?