Include payloadType in FrameInfo

So that consumers of onFrame can tell what codec the frame is in and
know what decoder to use.

Author: singpolyma

include/rtc/frameinfo.hpp

@@ -14,7 +14,8 @@
 namespace rtc {
 
 struct RTC_CPP_EXPORT FrameInfo {
-	FrameInfo(uint32_t timestamp) : timestamp(timestamp){};
+	FrameInfo(uint8_t payloadType, uint32_t timestamp) : payloadType(payloadType), timestamp(timestamp){};
+	uint8_t payloadType; // Indicates codec of the frame
 	uint32_t timestamp = 0; // RTP Timestamp
 };
 

include/rtc/h264rtpdepacketizer.hpp

@@ -33,7 +33,7 @@ class RTC_CPP_EXPORT H264RtpDepacketizer : public MediaHandler {
 	std::vector<message_ptr> mRtpBuffer;
 
 	message_vector buildFrames(message_vector::iterator firstPkt, message_vector::iterator lastPkt,
-	                           uint32_t timestamp);
+	                           uint8_t payloadType, uint32_t timestamp);
 };
 
 } // namespace rtc

src/h264rtpdepacketizer.cpp

@@ -32,10 +32,10 @@ const uint8_t naluTypeSTAPA = 24;
 const uint8_t naluTypeFUA = 28;
 
 message_vector H264RtpDepacketizer::buildFrames(message_vector::iterator begin,
-                                                message_vector::iterator end, uint32_t timestamp) {
+                                                message_vector::iterator end, uint8_t payloadType, uint32_t timestamp) {
 	message_vector out = {};
 	auto fua_buffer = std::vector<std::byte>{};
-	auto frameInfo = std::make_shared<FrameInfo>(timestamp);
+	auto frameInfo = std::make_shared<FrameInfo>(payloadType, timestamp);
 
 	for (auto it = begin; it != end; it++) {
 		auto pkt = it->get();
@@ -111,6 +111,7 @@ void H264RtpDepacketizer::incoming(message_vector &messages, const message_callb
 	               messages.end());
 
 	while (mRtpBuffer.size() != 0) {
+		uint8_t payload_type = 0;
 		uint32_t current_timestamp = 0;
 		size_t packets_in_timestamp = 0;
 
@@ -119,6 +120,7 @@ void H264RtpDepacketizer::incoming(message_vector &messages, const message_callb
 
 			if (current_timestamp == 0) {
 				current_timestamp = p->timestamp();
+				payload_type = p->payloadType(); // should all be the same for data of the same codec
 			} else if (current_timestamp != p->timestamp()) {
 				break;
 			}
@@ -133,7 +135,7 @@ void H264RtpDepacketizer::incoming(message_vector &messages, const message_callb
 		auto begin = mRtpBuffer.begin();
 		auto end = mRtpBuffer.begin() + (packets_in_timestamp - 1);
 
-		auto frames = buildFrames(begin, end + 1, current_timestamp);
+		auto frames = buildFrames(begin, end + 1, payload_type, current_timestamp);
 		messages.insert(messages.end(), frames.begin(), frames.end());
 		mRtpBuffer.erase(mRtpBuffer.begin(), mRtpBuffer.begin() + packets_in_timestamp);
 	}

src/rtpdepacketizer.cpp

@@ -36,7 +36,7 @@ void RtpDepacketizer::incoming([[maybe_unused]] message_vector &messages,
 		auto headerSize = sizeof(rtc::RtpHeader) + pkt->csrcCount() + pkt->getExtensionHeaderSize();
 		result.push_back(make_message(message->begin() + headerSize, message->end(),
 		                              Message::Binary, 0, nullptr,
-		                              std::make_shared<FrameInfo>(pkt->timestamp())));
+		                              std::make_shared<FrameInfo>(pkt->payloadType(), pkt->timestamp())));
 	}
 
 	messages.swap(result);