refactor: 梳理 rtx 处理逻辑

This commit is contained in:
Johnny
2021-11-18 18:41:23 +08:00
parent b13a0f5b79
commit da0a7219e9
2 changed files with 61 additions and 24 deletions

View File

@@ -385,10 +385,10 @@ void WebRtcTransportImp::onStartWebRTC() {
_ssrc_to_track[track->offer_ssrc_rtx] = track;
//rtp pt --> MediaTrack
_pt_to_track.emplace(track->plan_rtp->pt, std::make_pair(false, track));
_pt_to_track.emplace(track->plan_rtp->pt, new WrappedRtpTrack(track, _twcc_ctx, *this));
if (track->plan_rtx) {
//rtx pt --> MediaTrack
_pt_to_track.emplace(track->plan_rtx->pt, std::make_pair(true, track));
_pt_to_track.emplace(track->plan_rtx->pt, new WrappedRtxTrack(track));
}
if (m_offer->type != TrackApplication) {
//记录rtp ext类型与id的关系方便接收或发送rtp时修改rtp ext id
@@ -691,43 +691,51 @@ void WebRtcTransportImp::onRtp(const char *buf, size_t len, uint64_t stamp_ms) {
WarnL << "unknown rtp pt:" << (int)rtp->pt;
return;
}
bool is_rtx = it->second.first;
it->second->inputRtp(buf, len, stamp_ms, rtp);
}
void WrappedRtpTrack::inputRtp(const char *buf, size_t len, uint64_t stamp_ms, RtpHeader *rtp) {
auto ssrc = ntohl(rtp->ssrc);
auto &track = it->second.second;
//修改ext id至统一
string rid;
auto twcc_ext = track->rtp_ext_ctx->changeRtpExtId(rtp, true, &rid, RtpExtType::transport_cc);
if (twcc_ext && !is_rtx) {
if (twcc_ext) {
_twcc_ctx.onRtp(ssrc, twcc_ext.getTransportCCSeq(), stamp_ms);
}
auto &ref = track->rtp_channel[rid];
if (!ref) {
if (is_rtx) {
//再接收到对应的rtp前丢弃rtx包
WarnL << "unknown rtx rtp, rid:" << rid << ", ssrc:" << ssrc << ", codec:" << track->plan_rtp->codec << ", seq:" << ntohs(rtp->seq);
return;
}
createRtpChannel(rid, ssrc, *track);
_transport.createRtpChannel(rid, ssrc, *track);
}
if (!is_rtx) {
//这是普通的rtp数据
//这是普通的rtp数据
#if 0
auto seq = ntohs(rtp->seq);
if (track->media->type == TrackVideo && seq % 100 == 0) {
//此处模拟接受丢包
return;
}
auto seq = ntohs(rtp->seq);
if (track->media->type == TrackVideo && seq % 100 == 0) {
//此处模拟接受丢包
return;
}
#endif
//解析并排序rtp
ref->inputRtp(track->media->type, track->plan_rtp->sample_rate, (uint8_t *) buf, len, false);
//解析并排序rtp
ref->inputRtp(track->media->type, track->plan_rtp->sample_rate, (uint8_t *) buf, len, false);
}
void WrappedRtxTrack::inputRtp(const char *buf, size_t len, uint64_t stamp_ms, RtpHeader *rtp) {
//修改ext id至统一
string rid;
track->rtp_ext_ctx->changeRtpExtId(rtp, true, &rid, RtpExtType::transport_cc);
auto &ref = track->rtp_channel[rid];
if (!ref) {
//再接收到对应的rtp前丢弃rtx包
WarnL << "unknown rtx rtp, rid:" << rid << ", ssrc:" << ntohl(rtp->ssrc) << ", codec:" << track->plan_rtp->codec << ", seq:" << ntohs(rtp->seq);
return;
}
//这里是rtx重传包
//https://datatracker.ietf.org/doc/html/rfc4588#section-4
// https://datatracker.ietf.org/doc/html/rfc4588#section-4
auto payload = rtp->getPayloadData();
auto size = rtp->getPayloadSize(len);
if (size < 2) {
@@ -736,7 +744,7 @@ void WebRtcTransportImp::onRtp(const char *buf, size_t len, uint64_t stamp_ms) {
//前两个字节是原始的rtp的seq
auto origin_seq = payload[0] << 8 | payload[1];
//rtx 转换为 rtp
// rtx 转换为 rtp
rtp->pt = track->plan_rtp->pt;
rtp->seq = htons(origin_seq);
rtp->ssrc = htonl(ref->getSSRC());