diff options
Diffstat (limited to 'modules/rtp_rtcp/source/forward_error_correction.cc')
| -rw-r--r-- | modules/rtp_rtcp/source/forward_error_correction.cc | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/modules/rtp_rtcp/source/forward_error_correction.cc b/modules/rtp_rtcp/source/forward_error_correction.cc index 31303c8a..eeead407 100644 --- a/modules/rtp_rtcp/source/forward_error_correction.cc +++ b/modules/rtp_rtcp/source/forward_error_correction.cc @@ -603,6 +603,23 @@ void ForwardErrorCorrection::InsertPackets( while (!received_packet_list->empty()) { ReceivedPacket* rx_packet = received_packet_list->front(); + // Check for discarding oldest FEC packet, to avoid wrong FEC decoding from + // sequence number wrap-around. Detection of old FEC packet is based on + // sequence number difference of received packet and oldest packet in FEC + // packet list. + // TODO(marpan/holmer): We should be able to improve detection/discarding of + // old FEC packets based on timestamp information or better sequence number + // thresholding (e.g., to distinguish between wrap-around and reordering). + if (!fec_packet_list_.empty()) { + uint16_t seq_num_diff = abs( + static_cast<int>(rx_packet->seq_num) - + static_cast<int>(fec_packet_list_.front()->seq_num)); + if (seq_num_diff > 0x3fff) { + DiscardFECPacket(fec_packet_list_.front()); + fec_packet_list_.pop_front(); + } + } + if (rx_packet->is_fec) { InsertFECPacket(rx_packet, recovered_packet_list); } else { |