ROS2 Bag Exporter

Overview

ROS2 Bag Exporter is a versatile ROS 2 (Humble Hawksbill) c++ package designed to export ROS 2 bag files (rosbag2) into various formats, including images, point cloud data (PCD) files, IMU data, and GPS data. This tool facilitates the extraction and conversion of data from bag files for analysis, visualization, and processing outside the ROS ecosystem.

Features

Support for Multiple Message Types:

• PointCloud2: Export point cloud data to PCD files.
• Image: Convert image messages to PNG format.
• IR Image: Convert IR image messages to PNG format.
• DepthImage: Export depth images with appropriate encoding.
• LaserScan: Export laser scan data.
• IMU: Export IMU data for inertial measurement analysis.
• GPS: Export GPS coordinates and data.

Configurable Export Settings:

• Define input bag files, output directories, and storage formats via a YAML configuration file.

Robust Error Handling:

• Comprehensive logging for easy troubleshooting.
• Graceful shutdown on critical errors.

Automatic Directory Management:

• Automatically creates necessary directories for each topic based on the configuration.

Install

Dependencies

Ensure that the following dependencies are installed on your system:

• ROS 2 Humble Hawksbill
• C++17 Compiler
• YAML-CPP
• OpenCV
• PCL (Point Cloud Library)
• CV Bridge
• rosbag2_cpp
• ament_index_cpp

Installing Dependencies

You can install the necessary dependencies using apt:

sudo apt update
sudo apt install -y ros-humble-rclcpp ros-humble-rosbag2-cpp ros-humble-rosbag2-storage libyaml-cpp-dev libopencv-dev  ros-humble-cv-bridge ros-humble-sensor-msgs ros-humble-pcl-conversions ros-humble-pcl-ros libpcl-dev ros-humble-ament-index-cpp

Note: Replace 'humble' with your ROS 2 distribution if different.

Installation

1. Clone the Repository

Navigate to your ROS 2 workspace's src directory and clone the ros2_bag_exporter repository:

cd ~/ros2_ws/src
git clone https://github.com/yourusername/ros2_bag_exporter.git

Replace the repository URL with the actual repository URL.

2. Build the Package

Return to the root of your workspace and build the package using colcon:

cd ~/ros2_ws
source opt/ros/humble/setup.bash
colcon build --packages-select ros2_bag_exporter

3. Source the Workspace

After a successful build, source the workspace to overlay the new package:

source ~/ros2_ws/install/setup.bash

Tip: To automatically source the workspace upon opening a new terminal, add the above command to your shell's initialization file (e.g., ~/.bashrc).

Configuration

The behavior of ros2_bag_exporter is controlled via a YAML configuration file. By default, the configuration file is located at config/exporter_config.yaml within the package's share directory.

Configuration File Structure

bag_path: "/absolute/path/to/your/bagfile"
output_dir: "/absolute/path/to/output/directory"
storage_id: "sqlite3"  # Common storage ID; ensure it matches your bag's storage format
topics:
  - name: "/camera/depth/image_raw"
    type: "DepthImage"
    encoding: "16UC1"
    sample_interval: 10  # Write one sample every 10 messages
  - name: "/camera/color/image_raw"
    type: "Image"
    encoding: "rgb8"
    sample_interval: 5   # Write one sample every 5 messages
  - name: "/imu_topic"
    type: "IMU"
    sample_interval: 100  # Write one sample every 100 messages
  - name: "/gps_topic"
    type: "GPS"
    sample_interval: 100  # Write one sample every 100 messages
  - name: "/lidar/points"
    type: "PointCloud2"
    sample_interval: 10   # Write one sample every 10 messages

Parameter Descriptions

• bag_path: The absolute path to the ROS 2 bag file you wish to export.
• output_dir: The absolute path to the directory where exported files will be saved.
• storage_id: Specifies the storage format of the bag file. Common values include:
  • "sqlite3": Default storage for ROS 2 bags.
  • "mcap": For MCAP storage format.
• topics: A list of topics to export. Each topic requires:
  • name: The ROS 2 topic name.
  • type: The message type (PointCloud2, Image, DepthImage, IMU, GPS, etc.).
  • sample_interval: The interval at which messages will be written (e.g., 100 for every 100 messages).

Usage

After building and sourcing the workspace, run the bag_exporter node using the following command:

ros2 run ros2_bag_exporter bag_exporter

Command-Line Arguments

• --ros-args -p config_file:=<path_to_config>: Specify a custom path to the YAML configuration file.

Example

1. Sample Configuration

Create a configuration file at ros2_bag_exporter/share/ros2_bag_exporter/config/exporter_config.yaml with the following content:

bag_path: "/home/user/rosbags/sample_bag"
output_dir: "/home/user/rosbags/exported_data"
storage_id: "sqlite3"
topics:
  - name: "/camera/depth/image_raw"
    type: "DepthImage"
    encoding: "16UC1"
    sample_interval: 10
  - name: "/camera/color/image_raw"
    type: "Image"
    encoding: "rgb8"
    sample_interval: 5
  - name: "/imu_topic"
    type: "IMU"
    sample_interval: 100
  - name: "/gps_topic"
    type: "GPS"
    sample_interval: 100
  - name: "/lidar/points"
    type: "PointCloud2"
    sample_interval: 10

2. Running the Exporter

Execute the exporter node:

ros2 run ros2_bag_exporter bag_exporter

3. Verifying the Output

Navigate to the specified output directory to find the exported files organized by topic:

cd /home/user/rosbags/exported_data
ls

Troubleshooting

1. Package Not Found

Error:

Package 'ros2_bag_exporter' not found

Solution: Ensure you have built the workspace and sourced the workspace's setup.bash:

source ~/ros2_ws/install/setup.bash

2. Configuration File Loading Error

Error:

[ERROR] [rosbag2_exporter]: Failed to load configuration: bad file: config/exporter_config.yaml

Solution: Verify the existence and correctness of the YAML file.

3. Bag Storage Initialization Error

Error:

[ERROR] [rosbag2_storage]: No storage id specified, and no plugin found that could open URI

Solution: Ensure that storage_id matches the bag file storage format (e.g., sqlite3).

Contributing

Contributions are welcome! Please follow the standard process:

1. Fork the repository.
2. Create a feature branch.
3. Push your changes and submit a pull request.

License

This project is licensed under the Apache License 2.0.

Contact

Maintainer: Abdalrahman M. Amer

Email: abdalrahman.m5959@gmail.com

GitHub: Geekgineer