len = pick_stream(s, &rtsp_st, rt->recvbuf, len);
if (len > 0 && rtsp_st->transport_priv && rt->transport == RTSP_TRANSPORT_RTP)
ff_rtp_check_and_send_back_rr(rtsp_st->transport_priv, NULL, s->pb, len);
len = pick_stream(s, &rtsp_st, rt->recvbuf, len);
if (len > 0 && rtsp_st->transport_priv && rt->transport == RTSP_TRANSPORT_RTP)
ff_rtp_check_and_send_back_rr(rtsp_st->transport_priv, NULL, s->pb, len);