Does it work if you comment this out? Seems to do nothing useful, if i read the code right...
Code:
  //Self.LoadFromIntFImage(Self.FBitmapIntF);
  Self.FBitmapIntF.Free;
Also you don't need to use Self. that often It does give clarity in some cases, but many people don't do that. For example:
Code:
label1.caption := 'Test';
Looks tidier than with "Self".