Image Viewer

Real-time OpenCV viewer for stereo images, disparity maps, and depth data published by Hammerhead.

Build

cd hammerhead_ros2
colcon build --packages-up-to image_viewer

Usage

# Source the workspace
source install/setup.bash

ros2 run image_viewer_py image_viewer_py <image_topic>

Parameters

  • image_topic: ROS2 topic name that provides sensor_msgs::msg::Image messages

Examples

# Source the workspace
source install/setup.bash

# View raw left camera
ros2 run image_viewer image_viewer /nodar/left/image_raw

# View disparity map
ros2 run image_viewer image_viewer /nodar/disparity

Available Image Topics

Topic Description
/nodar/left/image_raw Raw left camera
/nodar/right/image_raw Raw right camera
/nodar/left/image_rect Rectified left image
/nodar/right/image_rect Rectified right image
/nodar/disparity Disparity map
/nodar/color_blended_depth/image_raw Color-coded depth visualization

Features

  • Support for all image topic types
  • Real-time display with OpenCV

Alternative Usage

You can also build and run this example using standalone CMake:

mkdir build && cd build
cmake .. && make
./image_viewer /nodar/left/image_raw

Integration with ROS2 Tools

There is nothing special about the image topics published by Hammerhead. You can also view then with tools like rviz2 and rqt.

Troubleshooting

  • No display appears: Check that Hammerhead is running and publishing image topics
  • Topic not found: Verify the topic name using ros2 topic list
  • Build errors: Ensure all dependencies are installed and workspace is sourced

Press Ctrl+C to exit the viewer.