各协议全面支持vp8/vp9/av1编码，ertmp新增支持opus编码 (#4498)

实现功能：
- rtp 增加vp8，vp9和av1编码支持
- 实现MP4录像所需的extra_data接口
- 扩展rtmp增加对opus、vp8、vp9和av1的支持

已知问题：
- 开启enhance rtmp后，ffmpeg暂时不支持播放vp8编码格式，其他格式的支持
- vp9和av1开始播放时容易遇到卡顿情况，过几秒后好了，原因暂时未知

---------

Co-authored-by: xia-chu <771730766@qq.com>

ext-codec/OpusRtmp.cpp

@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2016-present The ZLMediaKit project authors. All Rights Reserved.
+ *
+ * This file is part of ZLMediaKit(https://github.com/ZLMediaKit/ZLMediaKit).
+ *
+ * Use of this source code is governed by MIT-like 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 "OpusRtmp.h"
+#include "Rtmp/utils.h"
+#include "Common/config.h"
+#include "Extension/Factory.h"
+
+using namespace std;
+using namespace toolkit;
+
+namespace mediakit {
+
+void OpusRtmpDecoder::inputRtmp(const RtmpPacket::Ptr &pkt) {
+    auto data = pkt->data();
+    int size = pkt->size();
+    auto flags = (uint8_t)data[0];
+    auto codec = (RtmpAudioCodec)(flags >> 4);
+    auto type = flags & 0x0F;
+    data++; size--;
+    if (codec == RtmpAudioCodec::FOURCC) {
+        // @todo parse enhance audio header and check fourcc
+        data += 4;
+        size -= 4;
+        if (type == (uint8_t)RtmpPacketType::PacketTypeSequenceStart) {
+            getTrack()->setExtraData((uint8_t *)data, size);
+        } else {
+            outputFrame(data, size, pkt->time_stamp, pkt->time_stamp);
+        }
+    } else {
+        outputFrame(data, size, pkt->time_stamp, pkt->time_stamp);
+    } 
+}
+
+void OpusRtmpDecoder::outputFrame(const char *data, size_t size, uint32_t dts, uint32_t pts) {
+    RtmpCodec::inputFrame(Factory::getFrameFromPtr(getTrack()->getCodecId(), data, size, dts, pts));
+}
+
+////////////////////////////////////////////////////////////////////////
+OpusRtmpEncoder::OpusRtmpEncoder(const Track::Ptr &track) : RtmpCodec(track) {
+    _enhanced = mINI::Instance()[Rtmp::kEnhanced];
+}
+
+bool OpusRtmpEncoder::inputFrame(const Frame::Ptr &frame) {
+    auto packet = RtmpPacket::create();
+    if (_enhanced) {
+        uint8_t flags = ((uint8_t)RtmpAudioCodec::FOURCC << 4) | (uint8_t)RtmpPacketType::PacketTypeCodedFrames;
+        packet->buffer.push_back(flags);
+        packet->buffer.append("Opus", 4);
+    } else {
+        uint8_t flags = getAudioRtmpFlags(getTrack());
+        packet->buffer.push_back(flags);
+    }
+    packet->buffer.append(frame->data(), frame->size());
+    packet->body_size = packet->buffer.size();
+    packet->time_stamp = frame->dts();
+    packet->chunk_id = CHUNK_AUDIO;
+    packet->stream_index = STREAM_MEDIA;
+    packet->type_id = MSG_AUDIO;
+    // Output rtmp packet
+    RtmpCodec::inputRtmp(packet);
+    return true;
+}
+
+void OpusRtmpEncoder::makeConfigPacket() {
+    auto extra_data = getTrack()->getExtraData();
+    if (!extra_data || !extra_data->size())
+        return;
+    auto pkt = RtmpPacket::create();
+    if (_enhanced) {
+        uint8_t flags = ((uint8_t)RtmpAudioCodec::FOURCC << 4) | (uint8_t)RtmpPacketType::PacketTypeSequenceStart;
+        pkt->buffer.push_back(flags);
+        pkt->buffer.append("Opus", 4);
+    } else {
+        uint8_t flags = getAudioRtmpFlags(getTrack());
+        pkt->buffer.push_back(flags);
+    }
+    pkt->buffer.append(extra_data->data(), extra_data->size());
+    pkt->body_size = pkt->buffer.size();
+    pkt->chunk_id = CHUNK_AUDIO;
+    pkt->stream_index = STREAM_MEDIA;
+    pkt->time_stamp = 0;
+    pkt->type_id = MSG_AUDIO;
+    RtmpCodec::inputRtmp(pkt);
+}
+
+} // namespace mediakit