isaac_ros_bi3d

Source code on GitHub.

Quickstart

1. Set up your development environment by following the instructions here.

2. Clone isaac_ros_common and this repository under ${ISAAC_ROS_WS}/src.

   cd ${ISAAC_ROS_WS}/src
   

   git clone https://github.com/NVIDIA-ISAAC-ROS/isaac_ros_common.git
   

   git clone https://github.com/NVIDIA-ISAAC-ROS/isaac_ros_depth_segmentation.git
   

3. Pull down a rosbag of sample data:

   cd ${ISAAC_ROS_WS}/src/isaac_ros_depth_segmentation &&
   git lfs pull -X "" -I "resources/rosbags/bi3dnode_rosbag"
   

4. Launch the Docker container using the run_dev.sh script:

   cd ${ISAAC_ROS_WS}/src/isaac_ros_common &&
   ./scripts/run_dev.sh
   

5. Install this package’s dependencies.

sudo apt-get install -y ros-humble-isaac-ros-bi3d

6. Download model files for Bi3D (refer to the Model Preparation section for more information):

   mkdir -p /tmp/models/bi3d &&
   cd /tmp/models/bi3d &&
   wget 'https://api.ngc.nvidia.com/v2/models/nvidia/isaac/bi3d_proximity_segmentation/versions/2.0.0/files/featnet.onnx' &&
   wget 'https://api.ngc.nvidia.com/v2/models/nvidia/isaac/bi3d_proximity_segmentation/versions/2.0.0/files/segnet.onnx'
   

7. Convert the .onnx model files to TensorRT engine plan files (refer to the Model Preparation section for more information):

   If using Jetson (Generate engine plans with DLA support enabled):

   /usr/src/tensorrt/bin/trtexec --saveEngine=/tmp/models/bi3d/bi3dnet_featnet.plan \
   --onnx=/tmp/models/bi3d/featnet.onnx \
   --int8 --useDLACore=0 --allowGPUFallback &&
   /usr/src/tensorrt/bin/trtexec --saveEngine=/tmp/models/bi3d/bi3dnet_segnet.plan \
   --onnx=/tmp/models/bi3d/segnet.onnx \
   --int8 --useDLACore=0 --allowGPUFallback
   

   If using x86_64:

   /usr/src/tensorrt/bin/trtexec --saveEngine=/tmp/models/bi3d/bi3dnet_featnet.plan \
   --onnx=/tmp/models/bi3d/featnet.onnx --int8 &&
   /usr/src/tensorrt/bin/trtexec --saveEngine=/tmp/models/bi3d/bi3dnet_segnet.plan \
   --onnx=/tmp/models/bi3d/segnet.onnx --int8
   

   Note

   The engine plans generated using the x86_64 commands will also work on Jetson, but performance will be reduced.

8. Run the launch file to spin up a demo of this package:

   ros2 launch isaac_ros_bi3d isaac_ros_bi3d.launch.py featnet_engine_file_path:=/tmp/models/bi3d/bi3dnet_featnet.plan \
   segnet_engine_file_path:=/tmp/models/bi3d/bi3dnet_segnet.plan \
   max_disparity_values:=10 \
   image_height:=360 \
   image_width:=640
   

9. Open a second terminal inside the Docker container:

   cd ${ISAAC_ROS_WS}/src/isaac_ros_common && \
   ./scripts/run_dev.sh
   

10. Play the rosbag file to simulate image streams from the cameras:

    ros2 bag play --loop src/isaac_ros_depth_segmentation/resources/rosbags/bi3dnode_rosbag
    

11. Open two new terminals inside the Docker container for visualization:

    cd ${ISAAC_ROS_WS}/src/isaac_ros_common && \
    ./scripts/run_dev.sh
    

12. Visualize the output.

    Start disparity visualizer:

    ros2 run isaac_ros_bi3d isaac_ros_bi3d_visualizer.py --max_disparity_value 30
    

    Start image visualizer:

    ros2 run image_view image_view --ros-args -r image:=rgb_left
    

Try More Examples

To continue your exploration, check out the following suggested examples:

• Bi3D Example
• Tutorial with Isaac Sim
• Tutorial with ZED camera
• Tutorial with RealSense camera

Model Preparation

Download Pre-trained Models (.onnx) from NGC

The following steps show how to download pre-trained Bi3D DNN inference models.

1. The following model files must be downloaded to perform Bi3D inference. From File Browser on the Bi3D page, select the following .onnx model files in the FILE list and copy the wget command by clicking … in the ACTIONS column:

   • featnet.onnx

   • segnet.onnx

2. Run each of the copied commands in a terminal to download the ONNX model file, as shown in the example below:

   wget 'https://api.ngc.nvidia.com/v2/models/nvidia/isaac/bi3d_proximity_segmentation/versions/2.0.0/files/featnet.onnx' &&
   wget 'https://api.ngc.nvidia.com/v2/models/nvidia/isaac/bi3d_proximity_segmentation/versions/2.0.0/files/segnet.onnx'
   

   • Bi3D Featnet is a network that extracts features from stereo images.

   • Bi3D Segnet is an encoder-decoder segmentation network that generates a binary segmentation confidence map.

Convert the Pre-trained Models (.onnx) to TensorRT Engine Plans

trtexec is used to convert pre-trained models (.onnx) to the TensorRT engine plan and is included in the Isaac ROS docker container under /usr/src/tensorrt/bin/trtexec.

Tip: Use /usr/src/tensorrt/bin/trtexec -h for more information on using the tool.

Generating Engine Plans for Jetson

/usr/src/tensorrt/bin/trtexec --onnx=<PATH_TO_ONNX_MODEL_FILE> --saveEngine=<PATH_TO_WHERE_TO_SAVE_ENGINE_PLAN> --useDLACore=<SET_CORE_TO_ENABLE_DLA> --int8 --allowGPUFallback

Generating Engine Plans for x86_64

/usr/src/tensorrt/bin/trtexec --onnx=<PATH_TO_ONNX_MODEL_FILE> --saveEngine=<PATH_TO_WHERE_TO_SAVE_ENGINE_PLAN> --int8

Troubleshooting

Isaac ROS Troubleshooting

For solutions to problems with Isaac ROS, please check here.

Deep Learning Troubleshooting

For solutions to problems with using DNN models, please check here.

API

Usage

ros2 launch isaac_ros_bi3d isaac_ros_bi3d.launch.py featnet_engine_file_path:=<PATH_TO_FEATNET_ENGINE> \
segnet_engine_file_path:=<PATH_TO_SEGNET_ENGINE \
max_disparity_values:=<MAX_NUMBER_OF_DISPARITY_VALUES_USED> \
image_height:=<INPUT_IMAGE_HEIGHT> \
image_width:=<INPUT_IMAGE_WIDTH>

Interpreting the Output

The isaas_ros_bi3d package outputs a disparity image given a list of disparity values (planes). Each pixel of the output image that is not freespace is set to the value of the closest disparity plane (largest disparity value) that the pixel is deemed to be in front of. Each pixel that is predicted to be freespace is set to 0 (the furthest disparity/smallest disparity value). Freespace is defined as the region from the bottom of the image, up to the first pixel above which is not the ground plane. To find the boundary between freespace and not-freespace, one may start from the bottom of the image and, per column, find the first pixel that is not the ground plane. In the below example, the freespace of the image is shown in black:

The prediction of freespace eliminates the need for ground plane removal in the output image as a post-processing step, which is often applied to other stereo disparity functions. The output of isaas_ros_bi3d can be used to check if any pixels within the image breach a given proximity field by checking the values of all pixels. If a pixel value (disparity value) is larger than the disparity plane defining the proximity field, then it has breached that field. If a pixel does not breach any of the provided disparity planes, it is assigned a value of 0.

ROS Parameters

ROS Parameter	Type	Default	Description
image_height	uint16_t	576	The height of the input image
image_width	uint16_t	960	The width of the input image
featnet_engine_file_path	std::string	'path_to_featnet_engine'	The path to the Bi3D Featnet engine plan
segnet_engine_file_path	std::string	'path_to_segnet_engine'	The path to the Bi3D Segnet engine plan
max_disparity_values	int64_t	64	The maximum number of disparity values used for Bi3D inference. Isaac ROS Depth Segmentation supports up to a theoretical maximum of 64 disparity values during inference. However, the maximum length of disparities that a user may run in practice is dependent on the user’s hardware and availability of memory.
disparity_values	std::vector<int64_t>	{10, 20, 30, 40, 50, 60}	The specific threshold disparity values used for Bi3D inference. The number of disparity values must not exceed the value set in the max_disparity_values ROS parameter.

ROS Topics Subscribed

ROS Topic	Interface	Description
left_image_bi3d	sensor_msgs/Image	The message must be a ROS sensor_msgs/Image with rgb8 image encoding. 2. There should only be a single publisher node publishing to left_image_bi3d. Timing behavior with multiple publishers is not guaranteed by Bi3DNode and inference may not be performed on correct image pairs. Bi3D will process input pairs on a first available basis. Use a separate instance of Bi3DNode for each unique scene (publisher) that you wish to process.
right_image_bi3d	sensor_msgs/Image	The message must be a ROS sensor_msgs/Image with rgb8 image encoding. 2. There should only be a single publisher node publishing to right_image_bi3d. Timing behavior with multiple publishers is not guaranteed by Bi3DNode and inference may not be performed on correct image pairs. Bi3D will process inputs pairs on a first available basis. Use a separate instance of Bi3DNode for each unique scene (publisher) that you wish to process.
left_camera_info_bi3d	sensor_msgs/CameraInfo	Focal length populated in the Bi3D output disparity is extracted from this topic.
right_camera_info_bi3d	sensor_msgs/CameraInfo	Baseline populated in the Bi3D output disparity is extracted from this topic.

Note

The images on input topics (left_image_bi3d and right_image_bi3d) should be a color image in rgb8 format.

ROS Topics Published

ROS Topic	Interface	Description
bi3d_node/bi3d_output	stereo_msgs/DisparityImage	The depth segmentation of Bi3D given as a disparity image. For pixels not deemed freespace, their value is set to the closest (largest) disparity plane that is breached. A pixel value is set to 0 if it does not breach any disparity plane or if it is freespace.