From 75f86ba6c5204dc60c78366c0cd33a223d1955ae Mon Sep 17 00:00:00 2001
From: Martin Pulec <martin.pulec@cesnet.cz>
Date: Thu, 1 Aug 2024 11:55:38 +0200
Subject: [PATCH] rxtx/rtsp: delay server creation + tx callback

We pass the video_codec as RTSP parameters but until we receive first frame
we cannot know the actual codec, so that delay the creation until we receive
the first frame.
---
 src/rtsp/c_basicRTSPOnlyServer.cpp |  3 +++
 src/video_rxtx/h264_rtp.cpp        | 22 +++++++++++++++-------
 src/video_rxtx/h264_rtp.hpp        |  8 +++++++-
 3 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/src/rtsp/c_basicRTSPOnlyServer.cpp b/src/rtsp/c_basicRTSPOnlyServer.cpp
index 77885504b..d81b92885 100644
--- a/src/rtsp/c_basicRTSPOnlyServer.cpp
+++ b/src/rtsp/c_basicRTSPOnlyServer.cpp
@@ -64,6 +64,9 @@ c_start_server(struct rtsp_server_parameters params)
 }
 
 void c_stop_server(rtsp_serv_t* server){
+    if (server == nullptr) {
+        return;
+    }
     server->watch = 1;
     pthread_join(server->server_th, nullptr);
 }
diff --git a/src/video_rxtx/h264_rtp.cpp b/src/video_rxtx/h264_rtp.cpp
index 8bcb19c2f..18ed5731b 100644
--- a/src/video_rxtx/h264_rtp.cpp
+++ b/src/video_rxtx/h264_rtp.cpp
@@ -75,19 +75,27 @@ h264_rtp_video_rxtx::h264_rtp_video_rxtx(std::map<std::string, param_u> const &p
         rtsp_params.rtp_port = params.at("rx_port").i;  //server rtp port
         rtsp_params.rtp_port_audio = params.at("a_rx_port").i;
         rtsp_params.video_codec = H264;
-
-        m_rtsp_server = c_start_server(rtsp_params);
 }
 
 void
 h264_rtp_video_rxtx::send_frame(shared_ptr<video_frame> tx_frame) noexcept
 {
-        if (tx_frame->color_spec != H264) {
-                MSG(ERROR,
-                    "codecs other than H.264 currently not supported, got %s\n",
-                    get_codec_name(tx_frame->color_spec));
+        if (m_rtsp_server == nullptr) {
+                if (tx_frame->color_spec == H264) {
+                        tx_send_std = tx_send_h264;
+                } else {
+                        MSG(ERROR,
+                            "codecs other than H.264 currently not "
+                            "supported, got %s\n",
+                            get_codec_name(tx_frame->color_spec));
+                        return;
+                }
+                rtsp_params.video_codec = tx_frame->color_spec;
+                m_rtsp_server = c_start_server(rtsp_params);
         }
-        tx_send_h264(m_tx, tx_frame.get(), m_network_device);
+
+        tx_send_std(m_tx, tx_frame.get(), m_network_device);
+
         if ((m_rxtx_mode & MODE_RECEIVER) == 0) { // send RTCP (receiver thread would otherwise do this
                 time_ns_t curr_time = get_time_in_ns();
                 uint32_t ts = (curr_time - m_start_time) / 100'000 * 9; // at 90000 Hz
diff --git a/src/video_rxtx/h264_rtp.hpp b/src/video_rxtx/h264_rtp.hpp
index 88216a588..1636eb4f3 100644
--- a/src/video_rxtx/h264_rtp.hpp
+++ b/src/video_rxtx/h264_rtp.hpp
@@ -46,6 +46,10 @@
 #include "video_rxtx.hpp"
 #include "video_rxtx/rtp.hpp"
 
+struct rtp;
+struct tx;
+struct video_frame;
+
 class h264_rtp_video_rxtx : public rtp_video_rxtx {
 public:
         h264_rtp_video_rxtx(std::map<std::string, param_u> const &, int);
@@ -57,7 +61,9 @@ private:
                 return NULL;
         }
         struct rtsp_server_parameters rtsp_params;
-        rtsp_serv_t *m_rtsp_server;
+        rtsp_serv_t                  *m_rtsp_server = nullptr;
+        void (*tx_send_std)(struct tx *tx_session, struct video_frame *frame,
+                            struct rtp *rtp_session);
 };
 
 #endif // VIDEO_RXTX_H264_RTP_H_