semantic_inference

This repository provides code for running inference on images with pre-trained models to provide both closed and open-set semantics. Closed-set and open-set segmentation are implemented as follows:

• Inference using dense 2D closed-set semantic segmentation models is implemented in c++ using TensorRT
• Inference using open-set segmentation models and language features is implemented in python

Both kinds of semantic segmentation have a ROS interface associated with them, split between c++ and python as appropriate.

Table of Contents

• Credits
• Getting started
  • Closed-set
  • Open-set
• Usage

Credits

semantic_inference was primarily developed by Nathan Hughes at the MIT-SPARK Lab, assisted by Yun Chang, Jared Strader, Aaron Ray, and Dominic Maggio. A full list of contributors is maintaned here. We welcome additional contributions!

Getting started

The recommended use-case for the repository is with ROS. We assume some familiarity with ROS in these instructions. To start, clone this repository into your catkin workspace and run rosdep to get any missing dependencies. This usually looks like the following:

cd /path/to/catkin_ws/src
git clone git@github.com:MIT-SPARK/semantic_inference.git
rosdep install --from-paths . --ignore-src -r -y

An (optional) quick primer for setting up a minimal workspace is below for those less familiar with ROS.

Making a workspace

First, make sure rosdep is setup:

# Initialize necessary tools for working with ROS and catkin
sudo apt install python3-catkin-tools python3-rosdep
sudo rosdep init
rosdep update

Then, make the workspace and initialize it:

# Setup the workspace
mkdir -p path/to/catkin_ws/src
cd catkin_ws
catkin init
catkin config -DCMAKE_BUILD_TYPE=Release

Once you've added this repository to your workspace, follow one (or both) of the following setup-guides as necessary:

• Closed-Set
• Open-Set

Note
Some of our other (larger) packages have or will have more accessible guides to getting semantic_inference set up for specific applications, such as Hydra, Khronos or Clio.

Usage

semantic_inference is not intended for standalone usage. Instead, the intention is for the launch files in semantic_inference to be used in a larger project. More details about including them can be found in the closed-set and open-set documentation. However, it is possible to do something like

roslaunch semantic_inference_ros semantic_inference.launch

and then

rosbag play path/to/rosbag /some/color/image/topic:=/semantic_inference/color/image_raw

in a separate terminal to quickly test a particular segmentation model.

Note
This usage (remapping the rosbag output topic) is a little bit backwards from how remappings from ROS are normally specified and is because launch files are unable to take remappings from the command line.