From dad9f04a811c8e1800ecd08eddbcbb445e169be4 Mon Sep 17 00:00:00 2001 From: Andreas Eversberg Date: Thu, 14 Mar 2013 09:41:18 +0100 Subject: Drop bad speech frames rather than forwarding them via RTP Some RTP endpoints may not check for bad frame indications, so a frame that is marked as bad may be still decoded, which creates anoying noise. This patch drops these frames. It depends on the SIP endpoint how these dropped frames are handled. (insert silence, extrapolate speech...) --- src/libtrau/rtp_proxy.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/src/libtrau/rtp_proxy.c b/src/libtrau/rtp_proxy.c index 3fb8b455b..8f931cf24 100644 --- a/src/libtrau/rtp_proxy.c +++ b/src/libtrau/rtp_proxy.c @@ -291,27 +291,36 @@ int rtp_send_frame(struct rtp_socket *rs, struct gsm_data_frame *frame) switch (frame->msg_type) { case GSM_TCHF_FRAME: + if ((frame->data[0] >> 4) != 0xd) + goto bfi; payload_type = RTP_PT_GSM_FULL; payload_len = 33; duration = 160; break; case GSM_TCHF_FRAME_EFR: + if ((frame->data[0] >> 4) != 0xc) + goto bfi; payload_type = (dynamic_pt) ? : RTP_PT_GSM_EFR; payload_len = 31; duration = 160; break; case GSM_TCHH_FRAME: + if ((frame->data[0] & 0xf0) != 0x00) + goto bfi; payload_type = (dynamic_pt) ? : RTP_PT_GSM_HALF; payload_len = 15; duration = 160; break; case GSM_TCH_FRAME_AMR: + if ((frame->data[1] & 0x04) != 0x04) + goto bfi; payload_type = (dynamic_pt) ? : RTP_PT_AMR; payload_len = frame->data[0]; duration = 160; amr = 1; break; case GSM_BAD_FRAME: +bfi: /* in case of a bad frame, just count and drop packt */ payload_type = 0; payload_len = 0; -- cgit v1.2.3