ZLMediaKit/webrtc/Sdp.cpp
2021-04-15 19:40:17 +08:00

1570 lines
52 KiB
C++
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*
* Copyright (c) 2016 The ZLMediaKit project authors. All Rights Reserved.
*
* This file is part of ZLMediaKit(https://github.com/xia-chu/ZLMediaKit).
*
* Use of this source code is governed by MIT license that can be found in the
* LICENSE file in the root of the source tree. All contributing project authors
* may be found in the AUTHORS file in the root of the source tree.
*/
#include "Sdp.h"
#include "Rtsp/Rtsp.h"
#include <inttypes.h>
using namespace mediakit;
using onCreateSdpItem = function<SdpItem::Ptr(const string &key, const string &value)>;
static map<string, onCreateSdpItem, StrCaseCompare> sdpItemCreator;
template <typename Item>
void registerSdpItem(){
onCreateSdpItem func = [](const string &key, const string &value) {
auto ret = std::make_shared<Item>();
ret->parse(value);
return ret;
};
Item item;
sdpItemCreator.emplace(item.getKey(), std::move(func));
}
class DirectionInterface {
public:
virtual RtpDirection getDirection() const = 0;
};
class SdpDirectionSendonly : public SdpItem, public DirectionInterface{
public:
const char* getKey() const override { return getRtpDirectionString(getDirection());}
RtpDirection getDirection() const override {return RtpDirection::sendonly;}
};
class SdpDirectionRecvonly : public SdpItem, public DirectionInterface{
public:
const char* getKey() const override { return getRtpDirectionString(getDirection());}
RtpDirection getDirection() const override {return RtpDirection::recvonly;}
};
class SdpDirectionSendrecv : public SdpItem, public DirectionInterface{
public:
const char* getKey() const override { return getRtpDirectionString(getDirection());}
RtpDirection getDirection() const override {return RtpDirection::sendrecv;}
};
class SdpDirectionInactive : public SdpItem, public DirectionInterface{
public:
const char* getKey() const override { return getRtpDirectionString(getDirection());}
RtpDirection getDirection() const override {return RtpDirection::inactive;}
};
class DirectionInterfaceImp : public SdpItem, public DirectionInterface{
public:
DirectionInterfaceImp(RtpDirection direct){
direction = direct;
}
const char* getKey() const override { return getRtpDirectionString(getDirection());}
RtpDirection getDirection() const override {return direction;}
private:
RtpDirection direction;
};
static bool registerAllItem(){
registerSdpItem<SdpString<'v'> >();
registerSdpItem<SdpString<'s'> >();
registerSdpItem<SdpString<'i'> >();
registerSdpItem<SdpString<'u'> >();
registerSdpItem<SdpString<'e'> >();
registerSdpItem<SdpString<'p'> >();
registerSdpItem<SdpString<'z'> >();
registerSdpItem<SdpString<'k'> >();
registerSdpItem<SdpString<'r'> >();
registerSdpItem<SdpTime>();
registerSdpItem<SdpOrigin>();
registerSdpItem<SdpConnection>();
registerSdpItem<SdpBandwidth>();
registerSdpItem<SdpMedia>();
registerSdpItem<SdpAttr>();
registerSdpItem<SdpAttrGroup>();
registerSdpItem<SdpAttrMsidSemantic>();
registerSdpItem<SdpAttrRtcp>();
registerSdpItem<SdpAttrIceUfrag>();
registerSdpItem<SdpAttrIcePwd>();
registerSdpItem<SdpAttrIceOption>();
registerSdpItem<SdpAttrFingerprint>();
registerSdpItem<SdpAttrSetup>();
registerSdpItem<SdpAttrMid>();
registerSdpItem<SdpAttrExtmap>();
registerSdpItem<SdpAttrRtpMap>();
registerSdpItem<SdpAttrRtcpFb>();
registerSdpItem<SdpAttrFmtp>();
registerSdpItem<SdpAttrSSRC>();
registerSdpItem<SdpAttrSSRCGroup>();
registerSdpItem<SdpAttrSctpMap>();
registerSdpItem<SdpAttrCandidate>();
registerSdpItem<SdpDirectionSendonly>();
registerSdpItem<SdpDirectionRecvonly>();
registerSdpItem<SdpDirectionSendrecv>();
registerSdpItem<SdpDirectionInactive>();
registerSdpItem<SdpAttrMsid>();
registerSdpItem<SdpAttrExtmapAllowMixed>();
registerSdpItem<SdpAttrRid>();
registerSdpItem<SdpAttrSimulcast>();
return true;
}
static map<string, DtlsRole, StrCaseCompare> dtls_role_map = {
{"active", DtlsRole::active},
{"passive", DtlsRole::passive},
{"actpass", DtlsRole::actpass}
};
DtlsRole getDtlsRole(const string &str) {
auto it = dtls_role_map.find(str);
return it == dtls_role_map.end() ? DtlsRole::invalid : it->second;
}
const char* getDtlsRoleString(DtlsRole role){
switch (role) {
case DtlsRole::active : return "active";
case DtlsRole::passive : return "passive";
case DtlsRole::actpass : return "actpass";
default: return "invalid";
}
}
static map<string, RtpDirection, StrCaseCompare> direction_map = {
{"sendonly", RtpDirection::sendonly},
{"recvonly", RtpDirection::recvonly},
{"sendrecv", RtpDirection::sendrecv},
{"inactive", RtpDirection::inactive}
};
RtpDirection getRtpDirection(const string &str) {
auto it = direction_map.find(str);
return it == direction_map.end() ? RtpDirection::invalid : it->second;
}
const char* getRtpDirectionString(RtpDirection val){
switch (val) {
case RtpDirection::sendonly : return "sendonly";
case RtpDirection::recvonly : return "recvonly";
case RtpDirection::sendrecv : return "sendrecv";
case RtpDirection::inactive : return "inactive";
default: return "invalid";
}
}
//////////////////////////////////////////////////////////////////////////////////////////
string RtcSdpBase::toString() const {
_StrPrinter printer;
for (auto &item : items) {
printer << item->getKey() << "=" << item->toString() << "\r\n";
}
return std::move(printer);
}
RtpDirection RtcSdpBase::getDirection() const{
for (auto &item : items) {
auto attr = dynamic_pointer_cast<SdpAttr>(item);
if (attr) {
auto dir = dynamic_pointer_cast<DirectionInterface>(attr->detail);
if (dir) {
return dir->getDirection();
}
}
}
return RtpDirection::invalid;
}
SdpItem::Ptr RtcSdpBase::getItem(char key_c, const char *attr_key) const {
for (auto item : items) {
string key(1, key_c);
if (strcasecmp(item->getKey(), key.data()) == 0) {
if (!attr_key) {
return item;
}
auto attr = dynamic_pointer_cast<SdpAttr>(item);
if (attr && !strcasecmp(attr->detail->getKey() , attr_key)) {
return attr->detail;
}
}
}
return SdpItem::Ptr();
}
int RtcSdpBase::getVersion() const {
return atoi(getStringItem('v').data());
}
SdpOrigin RtcSdpBase::getOrigin() const {
return getItemClass<SdpOrigin>('o');
}
string RtcSdpBase::getSessionName() const {
return getStringItem('s');
}
string RtcSdpBase::getSessionInfo() const {
return getStringItem('i');
}
SdpTime RtcSdpBase::getSessionTime() const{
return getItemClass<SdpTime>('t');
}
SdpConnection RtcSdpBase::getConnection() const {
return getItemClass<SdpConnection>('c');
}
SdpBandwidth RtcSdpBase::getBandwidth() const {
return getItemClass<SdpBandwidth>('b');
}
string RtcSdpBase::getUri() const {
return getStringItem('u');
}
string RtcSdpBase::getEmail() const {
return getStringItem('e');
}
string RtcSdpBase::getPhone() const {
return getStringItem('p');
}
string RtcSdpBase::getTimeZone() const {
return getStringItem('z');
}
string RtcSdpBase::getEncryptKey() const {
return getStringItem('k');
}
string RtcSdpBase::getRepeatTimes() const {
return getStringItem('r');
}
//////////////////////////////////////////////////////////////////////
void RtcSessionSdp::parse(const string &str) {
static auto flag = registerAllItem();
RtcSdpBase *media = nullptr;
auto lines = split(str, "\n");
for(auto &line : lines){
trim(line);
if(line.size() < 3 || line[1] != '='){
continue;
}
auto key = line.substr(0, 1);
auto value = line.substr(2);
if (!strcasecmp(key.data(), "m")) {
medias.emplace_back(RtcSdpBase());
media = &medias.back();
}
SdpItem::Ptr item;
auto it = sdpItemCreator.find(key);
if (it != sdpItemCreator.end()) {
item = it->second(key, value);
} else {
item = std::make_shared<SdpCommon>(key);
item->parse(value);
}
if (media) {
media->items.push_back(std::move(item));
} else {
items.push_back(std::move(item));
}
}
}
string RtcSessionSdp::toString() const {
_StrPrinter printer;
printer << RtcSdpBase::toString();
for (auto &media : medias) {
printer << media.toString();
}
return std::move(printer);
}
//////////////////////////////////////////////////////////////////////////////////////////
#define SDP_THROW() throw std::invalid_argument(StrPrinter << "解析sdp " << getKey() << " 字段失败:" << str)
#define SDP_THROW2() throw std::invalid_argument(StrPrinter << "生成sdp " << getKey() << " 字段失败")
void SdpTime::parse(const string &str) {
if (sscanf(str.data(), "%" SCNu64 " %" SCNu64, &start, &stop) != 2) {
SDP_THROW();
}
}
string SdpTime::toString() const {
if (value.empty()) {
value = to_string(start) + " " + to_string(stop);
}
return SdpItem::toString();
}
void SdpOrigin::parse(const string &str) {
auto vec = split(str, " ");
if (vec.size() != 6) {
SDP_THROW();
}
username = vec[0];
session_id = vec[1];
session_version = vec[2];
nettype = vec[3];
addrtype = vec[4];
address = vec[5];
}
string SdpOrigin::toString() const {
if (value.empty()) {
value = username + " " + session_id + " " + session_version + " " + nettype + " " + addrtype + " " + address;
}
return SdpItem::toString();
}
void SdpConnection::parse(const string &str) {
auto vec = split(str, " ");
if (vec.size() != 3) {
SDP_THROW();
}
nettype = vec[0];
addrtype = vec[1];
address = vec[2];
}
string SdpConnection::toString() const {
if (value.empty()) {
value = nettype + " " + addrtype + " " + address;
}
return SdpItem::toString();
}
void SdpBandwidth::parse(const string &str) {
auto vec = split(str, ":");
if (vec.size() != 2) {
SDP_THROW();
}
bwtype = vec[0];
bandwidth = atoi(vec[1].data());
}
string SdpBandwidth::toString() const {
if (value.empty()) {
value = bwtype + ":" + to_string(bandwidth);
}
return SdpItem::toString();
}
void SdpMedia::parse(const string &str) {
auto vec = split(str, " ");
if (vec.size() < 4) {
SDP_THROW();
}
type = getTrackType(vec[0]);
if (type == TrackInvalid) {
SDP_THROW();
}
port = atoi(vec[1].data());
proto = vec[2];
for (size_t i = 3; i < vec.size(); ++i) {
auto pt = atoi(vec[i].data());
if (type != TrackApplication && pt > 0xFF) {
SDP_THROW();
}
fmts.emplace_back(pt);
}
}
string SdpMedia::toString() const {
if (value.empty()) {
value = string(getTrackString(type)) + " " + to_string(port) + " " + proto;
for (auto fmt : fmts) {
value += ' ';
value += to_string(fmt);
}
}
return SdpItem::toString();
}
void SdpAttr::parse(const string &str) {
auto pos = str.find(':');
auto key = pos == string::npos ? str : str.substr(0, pos);
auto value = pos == string::npos ? string() : str.substr(pos + 1);
auto it = sdpItemCreator.find(key);
if (it != sdpItemCreator.end()) {
detail = it->second(key, value);
} else {
detail = std::make_shared<SdpCommon>(key);
detail->parse(value);
}
}
string SdpAttr::toString() const {
if (value.empty()) {
auto detail_value = detail->toString();
if (detail_value.empty()) {
value = detail->getKey();
} else {
value = string(detail->getKey()) + ":" + detail_value;
}
}
return SdpItem::toString();
}
void SdpAttrGroup::parse(const string &str) {
auto vec = split(str, " ");
if (vec.size() < 2) {
SDP_THROW();
}
type = vec[0];
vec.erase(vec.begin());
mids = std::move(vec);
}
string SdpAttrGroup::toString() const {
if (value.empty()) {
value = type;
for (auto mid : mids) {
value += ' ';
value += mid;
}
}
return SdpItem::toString();
}
void SdpAttrMsidSemantic::parse(const string &str) {
auto vec = split(str, " ");
if (vec.size() < 1) {
SDP_THROW();
}
msid = vec[0];
token = vec.size() > 1 ? vec[1] : "";
}
string SdpAttrMsidSemantic::toString() const {
if (value.empty()) {
if (token.empty()) {
value = string(" ") + msid;
} else {
value = string(" ") + msid + " " + token;
}
}
return SdpItem::toString();
}
void SdpAttrRtcp::parse(const string &str) {
auto vec = split(str, " ");
if (vec.size() != 4) {
SDP_THROW();
}
port = atoi(vec[0].data());
nettype = vec[1];
addrtype = vec[2];
address = vec[3];
}
string SdpAttrRtcp::toString() const {
if (value.empty()) {
value = to_string(port) + " " + nettype + " " + addrtype + " " + address;
}
return SdpItem::toString();
}
void SdpAttrIceOption::parse(const string &str){
auto vec = split(str, " ");
for (auto &v : vec) {
if (!strcasecmp(v.data(), "trickle")) {
trickle = true;
continue;
}
if (!strcasecmp(v.data(), "renomination")) {
renomination = true;
continue;
}
}
}
string SdpAttrIceOption::toString() const{
if (value.empty()) {
if (trickle && renomination) {
value = "trickle renomination";
} else if (trickle) {
value = "trickle";
} else if (renomination) {
value = "renomination";
}
}
return value;
}
void SdpAttrFingerprint::parse(const string &str) {
auto vec = split(str, " ");
if (vec.size() != 2) {
SDP_THROW();
}
algorithm = vec[0];
hash = vec[1];
}
string SdpAttrFingerprint::toString() const {
if (value.empty()) {
value = algorithm + " " + hash;
}
return SdpItem::toString();
}
void SdpAttrSetup::parse(const string &str) {
role = getDtlsRole(str);
if (role == DtlsRole::invalid) {
SDP_THROW();
}
}
string SdpAttrSetup::toString() const {
if (value.empty()) {
value = getDtlsRoleString(role);
}
return SdpItem::toString();
}
void SdpAttrExtmap::parse(const string &str) {
char buf[128] = {0};
char direction_buf[32] = {0};
if (sscanf(str.data(), "%" SCNd32 "/%31[^ ] %127s", &index, direction_buf, buf) != 3) {
if (sscanf(str.data(), "%" SCNd32 " %127s", &index, buf) != 2) {
SDP_THROW();
}
direction = RtpDirection::sendrecv;
} else {
direction = getRtpDirection(direction_buf);
}
ext = buf;
}
string SdpAttrExtmap::toString() const {
if (value.empty()) {
if(direction == RtpDirection::invalid || direction == RtpDirection::sendrecv){
value = to_string(index) + " " + ext;
} else {
value = to_string(index) + "/" + getRtpDirectionString(direction) + " " + ext;
}
}
return SdpItem::toString();
}
void SdpAttrRtpMap::parse(const string &str) {
char buf[32] = {0};
if (sscanf(str.data(), "%" SCNu8 " %31[^/]/%" SCNd32 "/%" SCNd32, &pt, buf, &sample_rate, &channel) != 4) {
if (sscanf(str.data(), "%" SCNu8 " %31[^/]/%" SCNd32, &pt, buf, &sample_rate) != 3) {
SDP_THROW();
}
if (getTrackType(getCodecId(buf)) == TrackAudio) {
//未指定通道数时且为音频时那么通道数默认为1
channel = 1;
}
}
codec = buf;
}
string SdpAttrRtpMap::toString() const {
if (value.empty()) {
value = to_string(pt) + " " + codec + "/" + to_string(sample_rate);
if (channel) {
value += '/';
value += to_string(channel);
}
}
return SdpItem::toString();
}
void SdpAttrRtcpFb::parse(const string &str_in) {
auto str = str_in + "\n";
char rtcp_type_buf[32] = {0};
if (2 != sscanf(str.data(), "%" SCNu8 " %31[^\n]", &pt, rtcp_type_buf)) {
SDP_THROW();
}
rtcp_type = rtcp_type_buf;
}
string SdpAttrRtcpFb::toString() const {
if (value.empty()) {
value = to_string(pt) + " " + rtcp_type;
}
return SdpItem::toString();
}
void SdpAttrFmtp::parse(const string &str) {
auto pos = str.find(' ');
if (pos == string::npos) {
SDP_THROW();
}
pt = atoi(str.substr(0, pos).data());
auto vec = split(str.substr(pos + 1), ";");
for (auto &item : vec) {
trim(item);
auto pos = item.find('=');
if(pos == string::npos){
fmtp.emplace(std::make_pair(item, ""));
} else {
fmtp.emplace(std::make_pair(item.substr(0, pos), item.substr(pos + 1)));
}
}
if (fmtp.empty()) {
SDP_THROW();
}
}
string SdpAttrFmtp::toString() const {
if (value.empty()) {
value = to_string(pt);
int i = 0;
for (auto &pr : fmtp) {
value += (i++ ? ';' : ' ');
value += pr.first + "=" + pr.second;
}
}
return SdpItem::toString();
}
void SdpAttrSSRC::parse(const string &str_in) {
auto str = str_in + '\n';
char attr_buf[32] = {0};
char attr_val_buf[128] = {0};
if (3 == sscanf(str.data(), "%" SCNu32 " %31[^:]:%127[^\n]", &ssrc, attr_buf, attr_val_buf)) {
attribute = attr_buf;
attribute_value = attr_val_buf;
} else if (2 == sscanf(str.data(), "%" SCNu32 " %31s[^\n]", &ssrc, attr_buf)) {
attribute = attr_buf;
} else {
SDP_THROW();
}
}
string SdpAttrSSRC::toString() const {
if (value.empty()) {
value = to_string(ssrc) + ' ';
value += attribute;
if (!attribute_value.empty()) {
value += ':';
value += attribute_value;
}
}
return SdpItem::toString();
}
void SdpAttrSSRCGroup::parse(const string &str) {
auto vec = split(str, " ");
if (vec.size() == 3) {
if (vec[0] != "FID") {
SDP_THROW();
}
type = std::move(vec[0]);
u.fid.rtp_ssrc = atoll(vec[1].data()) & 0xFFFFFFFF;
u.fid.rtx_ssrc = atoll(vec[2].data()) & 0xFFFFFFFF;
} else if (vec.size() == 4) {
if (vec[0] != "SIM") {
SDP_THROW();
}
type = std::move(vec[0]);
u.sim.rtp_ssrc_low = atoll(vec[1].data()) & 0xFFFFFFFF;
u.sim.rtp_ssrc_mid = atoll(vec[2].data()) & 0xFFFFFFFF;
u.sim.rtp_ssrc_high = atoll(vec[3].data()) & 0xFFFFFFFF;
} else {
SDP_THROW();
}
}
string SdpAttrSSRCGroup::toString() const {
if (value.empty()) {
if (isFID()) {
value = type + " " + to_string(u.fid.rtp_ssrc) + " " + to_string(u.fid.rtx_ssrc);
} else if (isSIM()) {
value = type + " " + to_string(u.sim.rtp_ssrc_low) + " " + to_string(u.sim.rtp_ssrc_mid) + " " + to_string(u.sim.rtp_ssrc_high);
} else {
SDP_THROW2();
}
}
return SdpItem::toString();
}
void SdpAttrSctpMap::parse(const string &str) {
char subtypes_buf[64] = {0};
if (3 == sscanf(str.data(), "%" SCNu16 " %63[^ ] %" SCNd32, &port, subtypes_buf, &streams)) {
subtypes = subtypes_buf;
} else {
SDP_THROW();
}
}
string SdpAttrSctpMap::toString() const {
if (value.empty()) {
value = to_string(port);
value += ' ';
value += subtypes;
value += ' ';
value += to_string(streams);
}
return SdpItem::toString();
}
void SdpAttrCandidate::parse(const string &str) {
char foundation_buf[32] = {0};
char transport_buf[16] = {0};
char address_buf[32] = {0};
char type_buf[16] = {0};
if (7 != sscanf(str.data(), "%31[^ ] %" SCNu32 " %15[^ ] %" SCNu32 " %31[^ ] %" SCNu16 " typ %15[^ ]",
foundation_buf, &component, transport_buf, &priority, address_buf, &port, type_buf)) {
SDP_THROW();
}
foundation = foundation_buf;
transport = transport_buf;
address = address_buf;
type = type_buf;
auto pos = str.find(type);
if (pos != string::npos) {
auto remain = str.substr(pos + type.size());
trim(remain);
if (!remain.empty()) {
auto vec = split(remain, " ");
string key;
for (auto &item : vec) {
if (key.empty()) {
key = item;
} else {
arr.emplace_back(std::make_pair(std::move(key), std::move(item)));
}
}
}
}
}
string SdpAttrCandidate::toString() const {
if (value.empty()) {
value = foundation + " " + to_string(component) + " " + transport + " " + to_string(priority) +
" " + address + " " + to_string(port) + " typ " + type;
for (auto &pr : arr) {
value += ' ';
value += pr.first;
value += ' ';
value += pr.second;
}
}
return SdpItem::toString();
}
void RtcSession::loadFrom(const string &str, bool check) {
RtcSessionSdp sdp;
sdp.parse(str);
version = sdp.getVersion();
origin = sdp.getOrigin();
session_name = sdp.getSessionName();
session_info = sdp.getSessionInfo();
connection = sdp.getConnection();
bandwidth = sdp.getBandwidth();
time = sdp.getSessionTime();
msid_semantic = sdp.getItemClass<SdpAttrMsidSemantic>('a', "msid-semantic");
for (auto &media : sdp.medias) {
auto mline = media.getItemClass<SdpMedia>('m');
switch (mline.type) {
case TrackVideo:
case TrackAudio:
case TrackApplication: break;
default: throw std::invalid_argument(StrPrinter << "不识别的media类型:" << mline.toString());
}
this->media.emplace_back();
auto &rtc_media = this->media.back();
rtc_media.type = mline.type;
rtc_media.mid = media.getStringItem('a', "mid");
rtc_media.proto = mline.proto;
rtc_media.type = mline.type;
rtc_media.port = mline.port;
rtc_media.addr = media.getItemClass<SdpConnection>('c');
rtc_media.ice_ufrag = media.getStringItem('a', "ice-ufrag");
rtc_media.ice_pwd = media.getStringItem('a', "ice-pwd");
rtc_media.role = media.getItemClass<SdpAttrSetup>('a', "setup").role;
rtc_media.fingerprint = media.getItemClass<SdpAttrFingerprint>('a', "fingerprint");
if (rtc_media.fingerprint.empty()) {
rtc_media.fingerprint = sdp.getItemClass<SdpAttrFingerprint>('a', "fingerprint");
}
rtc_media.ice_lite = media.getItem('a', "ice-lite").operator bool();
auto ice_options = media.getItemClass<SdpAttrIceOption>('a', "ice-options");
rtc_media.ice_trickle = ice_options.trickle;
rtc_media.ice_renomination = ice_options.renomination;
rtc_media.candidate = media.getAllItem<SdpAttrCandidate>('a', "candidate");
if (mline.type == TrackType::TrackApplication) {
rtc_media.sctp_port = atoi(media.getStringItem('a', "sctp-port").data());
rtc_media.sctpmap = media.getItemClass<SdpAttrSctpMap>('a', "sctpmap");
continue;
}
rtc_media.rtcp_addr = media.getItemClass<SdpAttrRtcp>('a', "rtcp");
rtc_media.direction = media.getDirection();
rtc_media.extmap = media.getAllItem<SdpAttrExtmap>('a', "extmap");
rtc_media.rtcp_mux = media.getItem('a', "rtcp-mux").operator bool();
rtc_media.rtcp_rsize = media.getItem('a', "rtcp-rsize").operator bool();
map<uint32_t, RtcSSRC> rtc_ssrc_map;
for (auto &ssrc : media.getAllItem<SdpAttrSSRC>('a', "ssrc")) {
auto &rtc_ssrc = rtc_ssrc_map[ssrc.ssrc];
rtc_ssrc.ssrc = ssrc.ssrc;
if (!strcasecmp(ssrc.attribute.data(), "cname")) {
rtc_ssrc.cname = ssrc.attribute_value;
continue;
}
if (!strcasecmp(ssrc.attribute.data(), "msid")) {
rtc_ssrc.msid = ssrc.attribute_value;
continue;
}
if (!strcasecmp(ssrc.attribute.data(), "mslabel")) {
rtc_ssrc.mslabel = ssrc.attribute_value;
continue;
}
if (!strcasecmp(ssrc.attribute.data(), "label")) {
rtc_ssrc.label = ssrc.attribute_value;
continue;
}
}
uint32_t ssrc_rtp = 0, ssrc_rtx = 0, ssrc_rtp_low = 0, ssrc_rtp_mid = 0, ssrc_rtp_high = 0;
auto ssrc_groups = media.getAllItem<SdpAttrSSRCGroup>('a', "ssrc-group");
for (auto &group : ssrc_groups) {
if (group.isFID()) {
ssrc_rtp = group.u.fid.rtp_ssrc;
ssrc_rtx = group.u.fid.rtx_ssrc;
} else if (group.isSIM()) {
ssrc_rtp_low = group.u.sim.rtp_ssrc_low;
ssrc_rtp_mid = group.u.sim.rtp_ssrc_mid;
ssrc_rtp_high = group.u.sim.rtp_ssrc_high;
}
}
if (!ssrc_rtp) {
//没有指定ssrc-group字段那么只有一个ssrc
if (rtc_ssrc_map.size() > 1) {
throw std::invalid_argument("sdp中不存在a=ssrc-group:FID字段,但是ssrc却有多个");
}
if (rtc_ssrc_map.size() == 1) {
ssrc_rtp = rtc_ssrc_map.begin()->second.ssrc;
}
}
for (auto &pr : rtc_ssrc_map) {
auto &rtc_ssrc = pr.second;
if (rtc_ssrc.ssrc == ssrc_rtp) {
rtc_media.rtp_ssrc = rtc_ssrc;
}
if (rtc_ssrc.ssrc == ssrc_rtx) {
rtc_media.rtx_ssrc = rtc_ssrc;
}
if (rtc_ssrc.ssrc == ssrc_rtp_low) {
rtc_media.rtp_ssrc_low = rtc_ssrc;
}
if (rtc_ssrc.ssrc == ssrc_rtp_mid) {
rtc_media.rtp_ssrc_mid = rtc_ssrc;
}
if (rtc_ssrc.ssrc == ssrc_rtp_high) {
rtc_media.rtp_ssrc_high = rtc_ssrc;
}
}
auto rtpmap_arr = media.getAllItem<SdpAttrRtpMap>('a', "rtpmap");
auto rtcpfb_arr = media.getAllItem<SdpAttrRtcpFb>('a', "rtcp-fb");
auto fmtp_aar = media.getAllItem<SdpAttrFmtp>('a', "fmtp");
//方便根据pt查找rtpmap,一个pt必有一条
map<uint8_t, SdpAttrRtpMap &> rtpmap_map;
//方便根据pt查找rtcp-fb,一个pt可能有多条或0条
multimap<uint8_t, SdpAttrRtcpFb &> rtcpfb_map;
//方便根据pt查找fmtp一个pt最多一条
map<uint8_t, SdpAttrFmtp &> fmtp_map;
for (auto &rtpmap : rtpmap_arr) {
if (!rtpmap_map.emplace(rtpmap.pt, rtpmap).second) {
//添加失败,有多条
throw std::invalid_argument(StrPrinter << "该pt存在多条a=rtpmap:" << rtpmap.pt);
}
}
for (auto &rtpfb : rtcpfb_arr) {
rtcpfb_map.emplace(rtpfb.pt, rtpfb);
}
for (auto &fmtp : fmtp_aar) {
if (!fmtp_map.emplace(fmtp.pt, fmtp).second) {
//添加失败,有多条
throw std::invalid_argument(StrPrinter << "该pt存在多条a=fmtp:" << fmtp.pt);
}
}
for (auto &pt : mline.fmts) {
//遍历所有编码方案的pt
rtc_media.plan.emplace_back();
auto &plan = rtc_media.plan.back();
auto rtpmap_it = rtpmap_map.find(pt);
if (rtpmap_it == rtpmap_map.end()) {
plan.pt = pt;
plan.codec = RtpPayload::getName(pt);
plan.sample_rate = RtpPayload::getClockRate(pt);
plan.channel = RtpPayload::getAudioChannel(pt);
} else {
plan.pt = rtpmap_it->second.pt;
plan.codec = rtpmap_it->second.codec;
plan.sample_rate = rtpmap_it->second.sample_rate;
plan.channel = rtpmap_it->second.channel;
}
auto fmtp_it = fmtp_map.find(pt);
if (fmtp_it != fmtp_map.end()) {
plan.fmtp = fmtp_it->second.fmtp;
}
for (auto rtpfb_it = rtcpfb_map.find(pt);
rtpfb_it != rtcpfb_map.end() && rtpfb_it->second.pt == pt; ++rtpfb_it) {
plan.rtcp_fb.emplace_back(rtpfb_it->second.rtcp_type);
}
}
}
group = sdp.getItemClass<SdpAttrGroup>('a', "group");
if (check) {
checkValid();
}
}
std::shared_ptr<SdpItem> wrapSdpAttr(SdpItem::Ptr item){
auto ret = std::make_shared<SdpAttr>();
ret->detail = std::move(item);
return ret;
}
static void toRtsp(vector <SdpItem::Ptr> &items) {
for (auto it = items.begin(); it != items.end();) {
switch ((*it)->getKey()[0]) {
case 'v':
case 'o':
case 's':
case 'i':
case 't':
case 'c':
case 'b':{
++it;
break;
}
case 'm': {
auto m = dynamic_pointer_cast<SdpMedia>(*it);
CHECK(m);
m->proto = "RTP/AVP";
++it;
break;
}
case 'a': {
auto attr = dynamic_pointer_cast<SdpAttr>(*it);
CHECK(attr);
if (!strcasecmp(attr->detail->getKey(), "rtpmap")
|| !strcasecmp(attr->detail->getKey(), "fmtp")) {
++it;
break;
}
}
default: {
it = items.erase(it);
break;
}
}
}
}
string RtcSession::toRtspSdp() const{
checkValid();
RtcSession copy = *this;
copy.media.clear();
for (auto &m : media) {
switch (m.type) {
case TrackAudio:
case TrackVideo: {
copy.media.emplace_back(m);
copy.media.back().plan.resize(1);
break;
}
default:
continue;
}
}
copy.session_name = "zlmediakit rtsp stream from webrtc";
auto sdp = copy.toRtcSessionSdp();
toRtsp(sdp->items);
int i = 0;
for (auto &m : sdp->medias) {
toRtsp(m.items);
m.items.push_back(wrapSdpAttr(std::make_shared<SdpCommon>("control", string("trackID=") + to_string(i++))));
}
return sdp->toString();
}
RtcSessionSdp::Ptr RtcSession::toRtcSessionSdp() const{
RtcSessionSdp::Ptr ret = std::make_shared<RtcSessionSdp>();
auto &sdp = *ret;
sdp.items.emplace_back(std::make_shared<SdpString<'v'> >(to_string(version)));
sdp.items.emplace_back(std::make_shared<SdpOrigin>(origin));
sdp.items.emplace_back(std::make_shared<SdpString<'s'> >(session_name));
if (!session_info.empty()) {
sdp.items.emplace_back(std::make_shared<SdpString<'i'> >(session_info));
}
sdp.items.emplace_back(std::make_shared<SdpTime>(time));
if(connection.empty()){
sdp.items.emplace_back(std::make_shared<SdpConnection>(connection));
}
if (!bandwidth.empty()) {
sdp.items.emplace_back(std::make_shared<SdpBandwidth>(bandwidth));
}
sdp.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrGroup>(group)));
sdp.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrMsidSemantic>(msid_semantic)));
for (auto &m : media) {
sdp.medias.emplace_back();
auto &sdp_media = sdp.medias.back();
auto mline = std::make_shared<SdpMedia>();
mline->type = m.type;
mline->port = m.port;
mline->proto = m.proto;
for (auto &p : m.plan) {
mline->fmts.emplace_back(p.pt);
}
if (m.type == TrackApplication) {
mline->fmts.emplace_back(m.sctp_port);
}
sdp_media.items.emplace_back(std::move(mline));
sdp_media.items.emplace_back(std::make_shared<SdpConnection>(m.addr));
if (!m.rtcp_addr.empty()) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrRtcp>(m.rtcp_addr)));
}
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrIceUfrag>(m.ice_ufrag)));
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrIcePwd>(m.ice_pwd)));
if (m.ice_trickle || m.ice_renomination) {
auto attr = std::make_shared<SdpAttrIceOption>();
attr->trickle = m.ice_trickle;
attr->renomination = m.ice_renomination;
sdp_media.items.emplace_back(wrapSdpAttr(attr));
}
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrFingerprint>(m.fingerprint)));
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrSetup>(m.role)));
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrMid>(m.mid)));
if (m.ice_lite) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpCommon>("ice-lite")));
}
for (auto &ext : m.extmap) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrExtmap>(ext)));
}
if (m.direction != RtpDirection::invalid) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<DirectionInterfaceImp>(m.direction)));
}
if (m.rtcp_mux) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpCommon>("rtcp-mux")));
}
if (m.rtcp_rsize) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpCommon>("rtcp-rsize")));
}
if(m.type != TrackApplication) {
for (auto &p : m.plan) {
auto rtp_map = std::make_shared<SdpAttrRtpMap>();
rtp_map->pt = p.pt;
rtp_map->codec = p.codec;
rtp_map->sample_rate = p.sample_rate;
rtp_map->channel = p.channel;
sdp_media.items.emplace_back(wrapSdpAttr(std::move(rtp_map)));
for (auto &fb : p.rtcp_fb) {
auto rtcp_fb = std::make_shared<SdpAttrRtcpFb>();
rtcp_fb->pt = p.pt;
rtcp_fb->rtcp_type = fb;
sdp_media.items.emplace_back(wrapSdpAttr(std::move(rtcp_fb)));
}
if (!p.fmtp.empty()) {
auto fmtp = std::make_shared<SdpAttrFmtp>();
fmtp->pt = p.pt;
fmtp->fmtp = p.fmtp;
sdp_media.items.emplace_back(wrapSdpAttr(std::move(fmtp)));
}
}
if (!m.rtp_ssrc.empty() && !m.rtx_ssrc.empty()) {
auto group = std::make_shared<SdpAttrSSRCGroup>();
group->type = "FID";
group->u.fid.rtp_ssrc = m.rtp_ssrc.ssrc;
group->u.fid.rtx_ssrc = m.rtx_ssrc.ssrc;
sdp_media.items.emplace_back(wrapSdpAttr(std::move(group)));
}
static auto addSSRCItem = [](const RtcSSRC &rtp_ssrc, vector<SdpItem::Ptr> &items) {
SdpAttrSSRC ssrc;
ssrc.ssrc = rtp_ssrc.ssrc;
ssrc.attribute = "cname";
ssrc.attribute_value = rtp_ssrc.cname;
items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrSSRC>(ssrc)));
if (!rtp_ssrc.msid.empty()) {
ssrc.attribute = "msid";
ssrc.attribute_value = rtp_ssrc.msid;
items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrSSRC>(ssrc)));
}
if (!rtp_ssrc.mslabel.empty()) {
ssrc.attribute = "mslabel";
ssrc.attribute_value = rtp_ssrc.mslabel;
items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrSSRC>(ssrc)));
}
if (!rtp_ssrc.label.empty()) {
ssrc.attribute = "label";
ssrc.attribute_value = rtp_ssrc.label;
items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrSSRC>(ssrc)));
}
};
if (!m.rtp_ssrc.empty()) {
addSSRCItem(m.rtp_ssrc, sdp_media.items);
}
if (!m.rtx_ssrc.empty()) {
addSSRCItem(m.rtx_ssrc, sdp_media.items);
}
bool enable_sim = false;
if (!m.rtp_ssrc_low.empty() && !m.rtp_ssrc_mid.empty() && !m.rtp_ssrc_high.empty()) {
auto group = std::make_shared<SdpAttrSSRCGroup>();
group->type = "SIM";
group->u.sim.rtp_ssrc_low = m.rtp_ssrc_low.ssrc;
group->u.sim.rtp_ssrc_mid = m.rtp_ssrc_mid.ssrc;
group->u.sim.rtp_ssrc_high = m.rtp_ssrc_high.ssrc;
sdp_media.items.emplace_back(wrapSdpAttr(std::move(group)));
enable_sim = true;
}
if (enable_sim) {
addSSRCItem(m.rtp_ssrc_low, sdp_media.items);
addSSRCItem(m.rtp_ssrc_mid, sdp_media.items);
addSSRCItem(m.rtp_ssrc_high, sdp_media.items);
}
} else {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrSctpMap>(m.sctpmap)));
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpCommon>("sctp-port", to_string(m.sctp_port))));
}
for (auto &cand : m.candidate) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrCandidate>(cand)));
}
}
return ret;
}
string RtcSession::toString() const{
checkValid();
return toRtcSessionSdp()->toString();
}
string RtcCodecPlan::getFmtp(const char *key) const{
for (auto &item : fmtp) {
if (strcasecmp(item.first.data(), key) == 0) {
return item.second;
}
}
return "";
}
const RtcCodecPlan *RtcMedia::getPlan(uint8_t pt) const{
for (auto &item : plan) {
if (item.pt == pt) {
return &item;
}
}
return nullptr;
}
const RtcCodecPlan *RtcMedia::getPlan(const char *codec) const{
for (auto &item : plan) {
if (strcasecmp(item.codec.data(), codec) == 0) {
return &item;
}
}
return nullptr;
}
const RtcCodecPlan *RtcMedia::getRelatedRtxPlan(uint8_t pt) const{
for (auto &item : plan) {
if (strcasecmp(item.codec.data(), "rtx") == 0) {
auto apt = atoi(item.getFmtp("apt").data());
if (pt == apt) {
return &item;
}
}
}
return nullptr;
}
void RtcMedia::checkValid() const{
CHECK(type != TrackInvalid);
CHECK(!mid.empty());
CHECK(!proto.empty());
CHECK(direction != RtpDirection::invalid || type == TrackApplication);
CHECK(!plan.empty() || type == TrackApplication );
bool send_rtp = (direction == RtpDirection::sendonly || direction == RtpDirection::sendrecv);
CHECK(!rtp_ssrc.empty() || !send_rtp);
auto rtx_plan = getPlan("rtx");
if (rtx_plan) {
//开启rtx后必须指定rtx_ssrc
//todo 此处不确定
// CHECK(!rtx_ssrc.empty() || !send_rtp);
}
}
void RtcSession::checkValid() const{
CHECK(version == 0);
CHECK(!origin.empty());
CHECK(!session_name.empty());
CHECK(!msid_semantic.empty());
CHECK(!media.empty());
CHECK(group.mids.size() <= media.size());
for (auto &item : media) {
item.checkValid();
}
}
const RtcMedia *RtcSession::getMedia(TrackType type) const{
for(auto &m : media){
if(m.type == type){
return &m;
}
}
return nullptr;
}
void RtcConfigure::RtcTrackConfigure::setDefaultSetting(TrackType type){
enable = true;
rtcp_mux = true;
rtcp_rsize = false;
group_bundle = true;
support_rtx = true;
support_red = false;
support_ulpfec = false;
ice_lite = true;
ice_trickle = true;
ice_renomination = false;
switch (type) {
case TrackAudio: {
//此处调整偏好的编码格式优先级
preferred_codec = {CodecAAC, CodecG711U, CodecG711A, CodecOpus};
rtcp_fb = {"transport-cc"};
extmap = {"1 urn:ietf:params:rtp-hdrext:ssrc-audio-level"};
break;
}
case TrackVideo: {
//此处调整偏好的编码格式优先级
preferred_codec = {CodecH264, CodecH265};
rtcp_fb = {"nack", "ccm fir", "nack pli", "goog-remb", "transport-cc"};
extmap = {"2 urn:ietf:params:rtp-hdrext:toffset",
"3 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time",
"4 urn:3gpp:video-orientation",
"5 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01",
"6 http://www.webrtc.org/experiments/rtp-hdrext/playout-delay"};
break;
}
case TrackApplication: {
enable = false;
break;
}
default: break;
}
}
void RtcConfigure::setDefaultSetting(string ice_ufrag,
string ice_pwd,
RtpDirection direction,
const SdpAttrFingerprint &fingerprint) {
video.setDefaultSetting(TrackVideo);
audio.setDefaultSetting(TrackAudio);
application.setDefaultSetting(TrackApplication);
video.ice_ufrag = audio.ice_ufrag = application.ice_ufrag = ice_ufrag;
video.ice_pwd = audio.ice_pwd = application.ice_pwd = ice_pwd;
video.direction = audio.direction = application.direction = direction;
video.fingerprint = audio.fingerprint = application.fingerprint = fingerprint;
}
void RtcConfigure::addCandidate(const SdpAttrCandidate &candidate, TrackType type) {
switch (type) {
case TrackAudio: {
audio.candidate.emplace_back(candidate);
break;
}
case TrackVideo: {
video.candidate.emplace_back(candidate);
break;
}
case TrackApplication: {
application.candidate.emplace_back(candidate);
break;
}
default: {
if (audio.group_bundle) {
audio.candidate.emplace_back(candidate);
}
if (video.group_bundle) {
video.candidate.emplace_back(candidate);
}
if (application.group_bundle) {
application.candidate.emplace_back(candidate);
}
break;
}
}
}
shared_ptr<RtcSession> RtcConfigure::createAnswer(const RtcSession &offer){
shared_ptr<RtcSession> ret = std::make_shared<RtcSession>();
ret->version = offer.version;
//todo 此处设置会话id与会话地址貌似没什么作用
ret->origin = offer.origin;
ret->session_name = offer.session_name;
ret->msid_semantic = offer.msid_semantic;
matchMedia(ret, TrackAudio, offer.media, audio);
matchMedia(ret, TrackVideo, offer.media, video);
matchMedia(ret, TrackApplication, offer.media, application);
if (ret->media.empty()) {
throw std::invalid_argument("生成的answer sdp中媒体个数为0");
}
//设置音视频端口复用
if (!offer.group.mids.empty()) {
for (auto &m : ret->media) {
ret->group.mids.emplace_back(m.mid);
}
}
return ret;
}
void RtcConfigure::matchMedia(shared_ptr<RtcSession> &ret, TrackType type, const vector<RtcMedia> &medias, const RtcTrackConfigure &configure){
if (!configure.enable) {
return;
}
bool check_profile = true;
bool check_codec = true;
RETRY:
for (auto &codec : configure.preferred_codec) {
for (auto &offer_media : medias) {
if (offer_media.type != type) {
continue;
}
if (offer_media.ice_lite && configure.ice_lite) {
WarnL << "answer sdp配置为ice_lite模式与offer sdp中的ice_lite模式冲突";
continue;
}
const RtcCodecPlan *offer_plan_ptr = nullptr;
for (auto &plan : offer_media.plan) {
//先检查编码格式是否为偏好
if (check_codec && getCodecId(plan.codec) != codec) {
continue;
}
//命中偏好的编码格式,然后检查规格
if (check_profile && !onCheckCodecProfile(plan, codec)) {
continue;
}
//找到中意的codec
offer_plan_ptr = &plan;
break;
}
if (!offer_plan_ptr) {
//offer中该媒体的所有的codec都不支持
continue;
}
RtcMedia answer_media;
answer_media.type = offer_media.type;
answer_media.mid = offer_media.mid;
answer_media.proto = offer_media.proto;
//todo(此处设置rtp端口貌似没什么作用)
answer_media.port = offer_media.port;
//todo(此处设置rtp的ip地址貌似没什么作用)
answer_media.addr = offer_media.addr;
//todo(此处设置rtcp地址貌似没什么作用)
answer_media.rtcp_addr = offer_media.rtcp_addr;
answer_media.rtcp_mux = offer_media.rtcp_mux && configure.rtcp_mux;
answer_media.rtcp_rsize = offer_media.rtcp_rsize && configure.rtcp_rsize;
answer_media.ice_trickle = offer_media.ice_trickle && configure.ice_trickle;
answer_media.ice_renomination = offer_media.ice_renomination && configure.ice_renomination;
answer_media.ice_ufrag = configure.ice_ufrag;
answer_media.ice_pwd = configure.ice_pwd;
answer_media.fingerprint = configure.fingerprint;
answer_media.ice_lite = configure.ice_lite;
answer_media.candidate = configure.candidate;
switch (offer_media.role) {
case DtlsRole::actpass :
case DtlsRole::active : {
answer_media.role = DtlsRole::passive;
break;
}
case DtlsRole::passive : {
answer_media.role = DtlsRole::active;
break;
}
default: continue;
}
switch (offer_media.direction) {
case RtpDirection::sendonly : {
if (configure.direction != RtpDirection::recvonly &&
configure.direction != RtpDirection::sendrecv) {
//我们不支持接收
continue;
}
answer_media.direction = RtpDirection::recvonly;
break;
}
case RtpDirection::recvonly : {
if (configure.direction != RtpDirection::sendonly &&
configure.direction != RtpDirection::sendrecv) {
//我们不支持发送
continue;
}
answer_media.direction = RtpDirection::sendonly;
break;
}
case RtpDirection::sendrecv : {
//对方支持发送接收,那么最终能力根据配置来决定
answer_media.direction = configure.direction;
break;
}
default: continue;
}
//添加媒体plan
answer_media.plan.emplace_back(*offer_plan_ptr);
onSelectPlan(answer_media.plan.back(), codec);
//添加rtx,red,ulpfec plan
if (configure.support_red || configure.support_rtx || configure.support_ulpfec) {
for (auto &plan : offer_media.plan) {
if (!strcasecmp(plan.codec.data(), "rtx")) {
if (configure.support_rtx && atoi(plan.getFmtp("apt").data()) == offer_plan_ptr->pt) {
answer_media.plan.emplace_back(plan);
}
continue;
}
if (!strcasecmp(plan.codec.data(), "red")) {
if (configure.support_red) {
answer_media.plan.emplace_back(plan);
}
continue;
}
if (!strcasecmp(plan.codec.data(), "ulpfec")) {
if (configure.support_ulpfec) {
answer_media.plan.emplace_back(plan);
}
continue;
}
}
}
//这是我们支持的扩展
unordered_set<string> extmap_set;
for (auto &ext : configure.extmap) {
SdpAttrExtmap ext_cfg;
ext_cfg.parse(ext);
extmap_set.emplace(ext_cfg.ext);
}
//对方和我方都支持的扩展,那么我们都支持
for (auto &ext : offer_media.extmap) {
if (extmap_set.find(ext.ext) != extmap_set.end()) {
answer_media.extmap.emplace_back(ext);
}
}
//我们支持的rtcp类型
unordered_set<string> rtcp_fb_set;
for (auto &fp : configure.rtcp_fb) {
rtcp_fb_set.emplace(fp);
}
vector<string> offer_rtcp_fb;
for (auto &fp : offer_plan_ptr->rtcp_fb) {
if (rtcp_fb_set.find(fp) != rtcp_fb_set.end()) {
//对方该rtcp被我们支持
offer_rtcp_fb.emplace_back(fp);
}
}
//修改为我们支持的rtcp-fb类型
answer_media.plan[0].rtcp_fb.swap(offer_rtcp_fb);
ret->media.emplace_back(answer_media);
return;
}
}
if (check_profile) {
//如果是由于检查profile导致匹配失败那么重试一次且不检查profile
check_profile = false;
goto RETRY;
}
if (check_codec) {
//如果是由于检查codec导致匹配失败那么重试一次且不检查codec
check_codec = false;
goto RETRY;
}
}
void RtcConfigure::setPlayRtspInfo(const string &sdp){
RtcSession session;
session.loadFrom(sdp, false);
for (auto &m : session.media) {
switch (m.type) {
case TrackVideo : {
_rtsp_video_plan = std::make_shared<RtcCodecPlan>(m.plan[0]);
video.preferred_codec.clear();
video.preferred_codec.emplace_back(getCodecId(_rtsp_video_plan->codec));
break;
}
case TrackAudio : {
_rtsp_audio_plan = std::make_shared<RtcCodecPlan>(m.plan[0]);
audio.preferred_codec.clear();
audio.preferred_codec.emplace_back(getCodecId(_rtsp_audio_plan->codec));
break;
}
default: break;
}
}
}
static const string kProfile{"profile-level-id"};
static const string kMode{"packetization-mode"};
bool RtcConfigure::onCheckCodecProfile(const RtcCodecPlan &plan, CodecId codec){
if (_rtsp_audio_plan && codec == getCodecId(_rtsp_audio_plan->codec)) {
if (plan.sample_rate != _rtsp_audio_plan->sample_rate || plan.channel != _rtsp_audio_plan->channel) {
//音频采样率和通道数必须相同
return false;
}
return true;
}
if (_rtsp_video_plan && codec == CodecH264 && getCodecId(_rtsp_video_plan->codec) == CodecH264) {
//h264时profile-level-id
if (strcasecmp(_rtsp_video_plan->fmtp[kProfile].data(), const_cast<RtcCodecPlan &>(plan).fmtp[kProfile].data())) {
//profile-level-id 不匹配
return false;
}
return true;
}
return true;
}
void RtcConfigure::onSelectPlan(RtcCodecPlan &plan, CodecId codec){
if (_rtsp_video_plan && codec == CodecH264 && getCodecId(_rtsp_video_plan->codec) == CodecH264) {
//h264时设置packetization-mod为一致
auto mode = _rtsp_video_plan->fmtp[kMode];
plan.fmtp[kMode] = mode.empty() ? "0" : mode;
}
}