Enhance Dockerfile and launch configuration for improved logging and UDP transport; update runtime dependencies and remove unnecessary dummy frames in video processing

Dockerfile

@@ -35,7 +35,11 @@ RUN apt-get update \
 COPY --from=build /ws/install /ws/install
 COPY docker-entrypoint.sh /ros_entrypoint.sh
 RUN chmod +x /ros_entrypoint.sh
+# Bake FastDDS UDP-only profile into the image so the shared-memory transport
+# fix applies regardless of how the container is started (compose or docker run).
+COPY fastdds_no_shm.xml /ws/fastdds_no_shm.xml
 ENV ROS_DISTRO=humble
+ENV FASTRTPS_DEFAULT_PROFILES_FILE=/ws/fastdds_no_shm.xml
 
 ## Make ROS and workspace overlays available for interactive shells
 RUN echo "source /opt/ros/${ROS_DISTRO}/setup.bash || true" > /etc/profile.d/ros2.sh \

apt-requirements.txt

@@ -3,6 +3,7 @@ build-essential
 cmake
 pkg-config
 libopencv-dev
+python3-opencv
 python3-rosdep
 python3-rosdistro
 software-properties-common

apt-runtime.txt

@@ -1,6 +1,11 @@
 libgstreamer1.0-0
 gstreamer1.0-plugins-base
 gstreamer1.0-plugins-good
+gstreamer1.0-plugins-bad
 gstreamer1.0-plugins-ugly
 libgstrtspserver-1.0-0
 python3-opencv
+ros-humble-ros2cli
+ros-humble-rclpy
+net-tools
+iputils-ping

docker-compose.yml

@@ -12,10 +12,11 @@ services:
       - RMW_IMPLEMENTATION=${RMW_IMPLEMENTATION:-}
       # GStreamer debug level (uncomment for verbose GStreamer logging)
       # - GST_DEBUG=${GST_DEBUG:-}
+      # FASTRTPS_DEFAULT_PROFILES_FILE is set in the Dockerfile (baked into image)
     # Ensure the node binds to non-localhost interface (disable local_only)
     # and subscribe to the actual image topic available on the host
 
-    command: ["image2rtsp.launch.py", "local_only:=false", "topic:=/camera/image"]
+    command: ["image2rtsp.launch.py", "local_only:=false", "topic:=/camera/image", "log_level:=debug"]
 
 
     restart: unless-stopped

fastdds_no_shm.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<!-- Force UDP transport only.
+     Shared memory transport fails between host and Docker container (different
+     PID namespaces) even with network_mode: host. Disabling it forces FastDDS
+     to use UDPv4, which works correctly over the loopback interface. -->
+<profiles xmlns="http://www.eprosima.com/XMLSchemas/fastRTPS_Profiles">
+    <transport_descriptors>
+        <transport_descriptor>
+            <transport_id>UDPv4Transport</transport_id>
+            <type>UDPv4</type>
+        </transport_descriptor>
+    </transport_descriptors>
+    <participant profile_name="default_participant" is_default_profile="true">
+        <rtps>
+            <userTransports>
+                <transport_id>UDPv4Transport</transport_id>
+            </userTransports>
+            <useBuiltinTransports>false</useBuiltinTransports>
+        </rtps>
+    </participant>
+</profiles>

launch/image2rtsp.launch.py

@@ -1,6 +1,8 @@
 import os
 from ament_index_python.packages import get_package_share_directory
 from launch import LaunchDescription
+from launch.actions import DeclareLaunchArgument
+from launch.substitutions import LaunchConfiguration
 from launch_ros.actions import Node
 
 def generate_launch_description():
@@ -10,13 +12,19 @@ def generate_launch_description():
       'parameters.yaml'
       )
 
+   log_level = LaunchConfiguration('log_level')
+
    return LaunchDescription([
+      DeclareLaunchArgument(
+         'log_level',
+         default_value='warn',
+         description='ROS logger level (debug, info, warn, error, fatal)'
+      ),
       Node(
          package='image2rtsp',
          executable='image2rtsp',
          name='image2rtsp',
          parameters=[config],
-         # Reduce runtime logging verbosity to WARN to avoid info spam in container logs
+         arguments=['--ros-args', '--log-level', log_level]
-         arguments=['--ros-args', '--log-level', 'warn']
       )
    ])

src/image2rtsp.cpp

@@ -69,7 +69,13 @@ Image2rtsp::Image2rtsp() : Node("image2rtsp"){
     framerate = extract_framerate(pipeline, 30);
     rtsp_server_add_url(mountpoint.c_str(), pipeline.c_str());
 
-    RCLCPP_DEBUG(this->get_logger(), "Stream available at rtsp://%s:%s%s", gst_rtsp_server_get_address(rtsp_server), port.c_str(), mountpoint.c_str());
+    const char *server_address = gst_rtsp_server_get_address(rtsp_server);
+    if (local_only) {
+        RCLCPP_DEBUG(this->get_logger(), "Stream available at rtsp://%s:%s%s", server_address, port.c_str(), mountpoint.c_str());
+    } else {
+        RCLCPP_DEBUG(this->get_logger(), "RTSP server bound to %s:%s%s", server_address, port.c_str(), mountpoint.c_str());
+        RCLCPP_DEBUG(this->get_logger(), "Connect clients using rtsp://<host-ip>:%s%s (0.0.0.0 is bind-only)", port.c_str(), mountpoint.c_str());
+    }
 }
 
 uint Image2rtsp::extract_framerate(const std::string& pipeline, uint default_framerate = 30) {

src/video.cpp

@@ -87,29 +87,9 @@ static void media_configure(GstRTSPMediaFactory *factory, GstRTSPMedia *media, g
         gst_app_src_set_max_bytes(node->appsrc, 0);
         gst_app_src_set_max_time(node->appsrc, 0);
 
-        /* create a minimal dummy preroll frame to satisfy pipeline preroll */
+        /* caps and first buffer are set by topic_callback from the real image
-        guint width = 2;
+         * so that caps always match the actual camera resolution/format.
-        guint height = 2;
+         * Pushing a dummy preroll with wrong caps breaks x264enc mid-stream. */
-        guint fr = node->framerate > 0 ? node->framerate : 30;
-        GstCaps *caps = gst_caps_new_simple("video/x-raw",
-                                           "format", G_TYPE_STRING, "RGB",
-                                           "width", G_TYPE_INT, width,
-                                           "height", G_TYPE_INT, height,
-                                           "framerate", GST_TYPE_FRACTION, fr, 1,
-                                           NULL);
-        gst_app_src_set_caps(node->appsrc, caps);
-
-        gsize buf_size = width * height * 3;
-        GstBuffer *buf = gst_buffer_new_allocate(NULL, buf_size, NULL);
-        GstMapInfo map;
-        if (gst_buffer_map(buf, &map, GST_MAP_WRITE)){
-            if (map.data) memset(map.data, 64, buf_size);
-            gst_buffer_unmap(buf, &map);
-        }
-        GST_BUFFER_FLAG_SET(buf, GST_BUFFER_FLAG_LIVE);
-        gst_app_src_push_buffer(node->appsrc, buf);
-
-        gst_caps_unref(caps);
         gst_object_unref(pipeline);
         return;
     } else {
@@ -199,6 +179,7 @@ void Image2rtsp::topic_callback(const sensor_msgs::msg::Image::SharedPtr msg){
         // Set caps from message
         caps = gst_caps_new_from_image(msg);
         gst_app_src_set_caps(appsrc, caps);
+        gst_caps_unref(caps);
         buf = gst_buffer_new_allocate(nullptr, msg->data.size(), nullptr);
         gst_buffer_fill(buf, 0, msg->data.data(), msg->data.size());
         GST_BUFFER_FLAG_SET(buf, GST_BUFFER_FLAG_LIVE);