while len frames demuxer parse if frames for frame in frames if dec is

        while len(s):
            frames = demuxer.parse(s)
            if frames:
                for frame in frames:
                    if dec is None:
                        dec = acodec.Decoder(demuxer.streams[frame[0]])
                    raw = dec.decode(frame[1])
                    if raw and raw.data:
                        if self.snd is None:
                            self.snd = sound.Output(int(raw.sample_rate), raw.channels, sound.AFMT_S16_LE, self.card )
                        self.snd.play(raw.data)
            s = buffer.read(512)