Natools

                 + Tools.Image_Length (Last_Run_Size) + Last_Run_Header_Size;
         end;
      else
         declare
            Largest_Prefix : constant Natural
              := (case Input_Length mod 3 is
                  when 1 => 15 * 3 + 1,
                  when 2 => ((62 - Natural (Last_Code)) * 4 - 1) * 3 + 2,
                  when 2 => ((61 - Natural (Last_Code)) * 4 - 1) * 3 + 2,
                  when others => 0);
            Prefix_Header_Size : constant Ada.Streams.Stream_Element_Count
              := (if Largest_Prefix > 0 then 1 else 0);
            Largest_Run : constant Positive := 64 * 3;
            Prefix_Size : constant Natural
              := Natural'Min (Largest_Prefix, Input_Length);
            Run_Count : constant Natural

                  Index := Index + Extra_Blocks * 3;
               end if;
            end;
         elsif Input'Length mod 3 = 2 then
            declare
               Extra_Blocks : constant Natural := Natural'Min
                 (Input'Length / 3,
                  (62 - Natural (Last_Code)) * 4 - 1);
                  (61 - Natural (Last_Code)) * 4 - 1);
            begin
               Output (Offset)
                 := Tools.Image (61 - Tools.Base_64_Digit (Extra_Blocks / 4));
               Offset := Offset + 1;

               Tools.Encode_Double
                 (Input (Index .. Index + 1),