Support composited bridges for 1:N protocols converting. v6.0.41 (#3392)

Co-authored-by: john <hondaxiao@tencent.com>
Co-authored-by: chundonglinlin <chundonglinlin@163.com>

trunk/src/app/srs_app_stream_bridge.hpp

@@ -0,0 +1,95 @@
+//
+// Copyright (c) 2013-2023 The SRS Authors
+//
+// SPDX-License-Identifier: MIT or MulanPSL-2.0
+//
+
+#ifndef SRS_APP_STREAM_BRIDGE_HPP
+#define SRS_APP_STREAM_BRIDGE_HPP
+
+#include <srs_core.hpp>
+
+#include <srs_kernel_codec.hpp>
+
+#include <vector>
+
+class SrsRequest;
+class SrsSharedPtrMessage;
+class SrsLiveSource;
+class SrsRtcSource;
+class SrsRtmpFormat;
+class SrsMetaCache;
+class SrsAudioTranscoder;
+class SrsRtpPacket;
+class SrsRtcRtpBuilder;
+
+// A stream bridge is used to convert stream via different protocols, such as bridge for RTMP and RTC. Generally, we use
+// frame as message for bridge. A frame is a audio or video frame, such as an I/B/P frame, a general frame for decoder.
+// So you must assemble RTP or TS packets to a video frame if WebRTC or SRT.
+class ISrsStreamBridge
+{
+public:
+    ISrsStreamBridge();
+    virtual ~ISrsStreamBridge();
+public:
+    virtual srs_error_t initialize(SrsRequest* r) = 0;
+    virtual srs_error_t on_publish() = 0;
+    virtual srs_error_t on_frame(SrsSharedPtrMessage* frame) = 0;
+    virtual void on_unpublish() = 0;
+};
+
+// A bridge to feed AV frame to RTMP stream.
+class SrsFrameToRtmpBridge : public ISrsStreamBridge
+{
+private:
+    SrsLiveSource *source_;
+public:
+    SrsFrameToRtmpBridge(SrsLiveSource *src);
+    virtual ~SrsFrameToRtmpBridge();
+public:
+    srs_error_t initialize(SrsRequest* r);
+public:
+    virtual srs_error_t on_publish();
+    virtual void on_unpublish();
+public:
+    virtual srs_error_t on_frame(SrsSharedPtrMessage* frame);
+};
+
+// A bridge to covert AV frame to WebRTC stream.
+class SrsFrameToRtcBridge : public ISrsStreamBridge
+{
+private:
+    SrsRtcSource* source_;
+    SrsRtcRtpBuilder* rtp_builder_;
+public:
+    SrsFrameToRtcBridge(SrsRtcSource* source);
+    virtual ~SrsFrameToRtcBridge();
+public:
+    virtual srs_error_t initialize(SrsRequest* r);
+    virtual srs_error_t on_publish();
+    virtual void on_unpublish();
+    virtual srs_error_t on_frame(SrsSharedPtrMessage* frame);
+    srs_error_t on_rtp(SrsRtpPacket* pkt);
+};
+
+// A bridge chain, a set of bridges.
+class SrsCompositeBridge : public ISrsStreamBridge
+{
+public:
+    SrsCompositeBridge();
+    virtual ~SrsCompositeBridge();
+public:
+    srs_error_t initialize(SrsRequest* r);
+public:
+    virtual srs_error_t on_publish();
+    virtual void on_unpublish();
+public:
+    virtual srs_error_t on_frame(SrsSharedPtrMessage* frame);
+public:
+    SrsCompositeBridge* append(ISrsStreamBridge* bridge);
+private:
+    std::vector<ISrsStreamBridge*> bridges_;
+};
+
+#endif
+