feat(ros2): add unified camera publisher base class

Introduce CarlaCameraPublisher as an abstract base class that manages
Image and CameraInfo via two PublisherImpl<T> instances. Migrate
CarlaRGBCameraPublisher to a thin subclass providing channel count and
encoding. Replace CarlaDepthCameraPublisher, CarlaNormalsCameraPublisher,
CarlaOpticalFlowCameraPublisher, CarlaSSCameraPublisher, and
CarlaISCameraPublisher with type aliases to CarlaRGBCameraPublisher,
eliminating ~2800 lines of duplicated boilerplate.

Signed-off-by: Yutaka Kondo <yutaka.kondo@youtalk.jp>

LibCarla/source/carla/ros2/publishers/CarlaCameraPublisher.cpp

@@ -0,0 +1,63 @@
+// Copyright (c) 2025 Computer Vision Center (CVC) at the Universitat Autonoma de Barcelona (UAB).
+// This work is licensed under the terms of the MIT license.
+// For a copy, see <https://opensource.org/licenses/MIT>.
+
+#include "CarlaCameraPublisher.h"
+
+namespace carla {
+namespace ros2 {
+
+std::vector<uint8_t> CarlaCameraPublisher::ComputeImage(uint32_t height, uint32_t width, const uint8_t *data) {
+  const size_t size = height * width * this->GetChannels() * sizeof(uint8_t);
+  std::vector<uint8_t> vector_data(data, data + size);
+  return vector_data;
+}
+
+bool CarlaCameraPublisher::WriteCameraInfo(int32_t seconds, uint32_t nanoseconds, uint32_t x_offset, uint32_t y_offset, uint32_t height, uint32_t width, float fov, bool do_rectify) {
+
+  _impl_camera_info->GetMessage()->header().stamp().sec(seconds);
+  _impl_camera_info->GetMessage()->header().stamp().nanosec(nanoseconds);
+  _impl_camera_info->GetMessage()->header().frame_id(GetFrameId());
+
+  const double cx = static_cast<double>(width) / 2.0;
+  const double cy = static_cast<double>(height) / 2.0;
+  const double fx = static_cast<double>(width) / (2.0 * std::tan(fov) * M_PI / 360.0);
+  const double fy = fx;
+
+  _impl_camera_info->GetMessage()->height(height);
+  _impl_camera_info->GetMessage()->width(width);
+  _impl_camera_info->GetMessage()->distortion_model("plumb_bob");
+  _impl_camera_info->GetMessage()->D({ 0.0, 0.0, 0.0, 0.0, 0.0 });
+  _impl_camera_info->GetMessage()->k({fx, 0.0, cx, 0.0, fy, cy, 0.0, 0.0, 1.0});
+  _impl_camera_info->GetMessage()->r({ 1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0 });
+  _impl_camera_info->GetMessage()->p({fx, 0.0, cx, 0.0, 0.0, fy, cy, 0.0, 0.0, 0.0, 1.0, 0.0});
+  _impl_camera_info->GetMessage()->binning_x(0);
+  _impl_camera_info->GetMessage()->binning_y(0);
+
+  _impl_camera_info->GetMessage()->roi().x_offset(x_offset);
+  _impl_camera_info->GetMessage()->roi().y_offset(y_offset);
+  _impl_camera_info->GetMessage()->roi().height(height);
+  _impl_camera_info->GetMessage()->roi().width(width);
+  _impl_camera_info->GetMessage()->roi().do_rectify(do_rectify);
+
+  return true;
+}
+
+bool CarlaCameraPublisher::WriteImage(int32_t seconds, uint32_t nanoseconds, uint32_t height, uint32_t width, std::vector<uint8_t> data) {
+  _impl_image->GetMessage()->header().stamp().sec(seconds);
+  _impl_image->GetMessage()->header().stamp().nanosec(nanoseconds);
+  _impl_image->GetMessage()->header().frame_id(this->GetFrameId());
+
+  _impl_image->GetMessage()->width(width);
+  _impl_image->GetMessage()->height(height);
+  _impl_image->GetMessage()->encoding(this->GetEncoding());
+  _impl_image->GetMessage()->is_bigendian(0);
+  _impl_image->GetMessage()->step(width * this->GetChannels() * sizeof(uint8_t));
+
+  _impl_image->GetMessage()->data(std::move(data)); // https://github.com/eProsima/Fast-DDS/issues/2330
+
+  return true;
+}
+
+}  // namespace ros2
+}  // namespace carla

LibCarla/source/carla/ros2/publishers/CarlaCameraPublisher.h

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+// Copyright (c) 2025 Computer Vision Center (CVC) at the Universitat Autonoma de Barcelona (UAB).
+// This work is licensed under the terms of the MIT license.
+// For a copy, see <https://opensource.org/licenses/MIT>.
+
+#pragma once
+
+#include <memory>
+#include <vector>
+
+#include "carla/ros2/publishers/BasePublisher.h"
+#include "carla/ros2/publishers/PublisherImpl.h"
+
+#include "carla/ros2/types/Image.h"
+#include "carla/ros2/types/ImagePubSubTypes.h"
+#include "carla/ros2/types/CameraInfo.h"
+#include "carla/ros2/types/CameraInfoPubSubTypes.h"
+
+namespace carla {
+namespace ros2 {
+
+  class CarlaCameraPublisher : public BasePublisher {
+    public:
+      struct ImageMsgTraits {
+        using msg_type = sensor_msgs::msg::Image;
+        using msg_pubsub_type = sensor_msgs::msg::ImagePubSubType;
+      };
+
+      struct CameraInfoMsgTraits {
+        using msg_type = sensor_msgs::msg::CameraInfo;
+        using msg_pubsub_type = sensor_msgs::msg::CameraInfoPubSubType;
+      };
+
+      CarlaCameraPublisher(std::string base_topic_name, std::string frame_id) :
+        BasePublisher(base_topic_name, frame_id),
+        _impl_image(std::make_shared<PublisherImpl<ImageMsgTraits>>()),
+        _impl_camera_info(std::make_shared<PublisherImpl<CameraInfoMsgTraits>>()) {
+          _impl_image->Init(GetBaseTopicName() + "/image");
+          _impl_camera_info->Init(GetBaseTopicName() + "/camera_info");
+        }
+
+      virtual uint8_t GetChannels() = 0;
+
+      bool Publish() {
+        return _impl_camera_info->Publish() && _impl_image->Publish();
+      }
+
+      bool WriteCameraInfo(int32_t seconds, uint32_t nanoseconds, uint32_t x_offset, uint32_t y_offset, uint32_t height, uint32_t width, float fov, bool do_rectify);
+      bool WriteImage(int32_t seconds, uint32_t nanoseconds, uint32_t height, uint32_t width, const uint8_t* data) {
+        return WriteImage(seconds, nanoseconds, height, width, ComputeImage(height, width, data));
+      }
+      bool WriteImage(int32_t seconds, uint32_t nanoseconds, uint32_t height, uint32_t width, std::vector<uint8_t> data);
+
+    private:
+      virtual std::string GetEncoding() = 0;
+
+      virtual std::vector<uint8_t> ComputeImage(uint32_t height, uint32_t width, const uint8_t* data);
+
+    private:
+      std::shared_ptr<PublisherImpl<ImageMsgTraits>> _impl_image;
+      std::shared_ptr<PublisherImpl<CameraInfoMsgTraits>> _impl_camera_info;
+  };
+
+}  // namespace ros2
+}  // namespace carla