ConvertUnsignedToSigned example for Delphi

procedure TForm1.Button1Click(Sender: TObject);
begin
   LEADImage1.LoadSigned:= True;
   { Load the bitmap, keeping the bits per pixel of the file }
   LEADImage1.Load( 'c:\Image1.tif', 0, 0, 1 );

   if ( Not LEADImage1.IsSigned) then
      { convert bitmap to signed }
      LEADImage1.ConvertUnsignedToSigned( PROCESS_RANGE_ONLY );
end;