Как сохранить все картинки TWebBrowser?

uses
  UrlMon;

function DownloadFile(SourceFile, DestFile: string): Boolean;
begin
  try
    Result := UrlDownloadToFile(nil, PChar(SourceFile), PChar(DestFile), 0,
      nil) = 0;
  except
    Result := False;
  end;
end;

procedure TForm1.Button1Click(Sender: TObject);
var
  k, p: Integer;
  Source, dest, ext: string;
begin
  for k := 0 to WebBrowser1.OleObject.Document.Images.Length - 1 do
  begin
    Source := WebBrowser1.OleObject.Document.Images.Item(k).Src;
    p := LastDelimiter('.', Source);
    ext := UpperCase(Copy(Source, p + 1, Length(Source)));
    if (ext = 'GIF') or (ext = 'JPG') then
    begin
      p  := LastDelimiter('/', Source);
      dest := ExtractFilePath(ParamStr(0)) + Copy(Source, p + 1,
        Length(Source));
      DownloadFile(Source, dest);
    end;
  end;
end;