how to eval image as text

I am saving into database a large text as image
so i have a column of type image ServiceDescription in database with value 0x2C78846D6C
how do i encode it and load it using eval 
 <asp:TemplateField HeaderText="ItemImage" SortExpression="ItemImage">                     <ItemTemplate>                                              <asp:Label ID="Label1" runat="server" Text='<%# BitConverter.ToString((byte[])Eval("ServiceDescription")) ) %>'></asp:Label>        &n ...