Как преобразовывать BMP в ICO?

type
TForm1 = class(TForm)
Button1: TButton;
procedure FormCreate(Sender: TObject);
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;
BitBuf: TBitMap;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
BitBuf:= TBitMap.Create;
BitBuf.LoadFromFile(’1.bmp’);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
BitBuf.SaveToFile(’1.ico’);
end;

end.