procedure TForm1.Button1Click(Sender: TObject);
var
len: Integer;
mp : TMediaPlayer;
begin
if OpenDialog1.Execute then
begin
mp := MediaPlayer1;
mp.FileName := OpenDialog1.FileName;
mp.TimeFormat := tfMilliseconds;
mp.Open;
len := Trunc(mp.Length / 1000);
Label16.Caption := mp.FileName;
Label17.Caption := Format('%d:%d:%d',[len div 3600, len div 60, len mod 60]);
mp.Close;
end;
end;