diff --git a/.github/workflows/ubuntu.yml b/.github/workflows/ubuntu.yml
index 9dc78ef..5fa7516 100644
--- a/.github/workflows/ubuntu.yml
+++ b/.github/workflows/ubuntu.yml
@@ -51,7 +51,7 @@ jobs:
run: |
echo "/usr/local/cuda-11.0/bin" >> $GITHUB_PATH
echo "$HOME/.local/bin" >> $GITHUB_PATH
- - name: local dependencies cache
+ - name: cache local dependencies
id: cache-local
uses: actions/cache@v2
with:
@@ -134,6 +134,12 @@ jobs:
- name: format check
run: make check-format
working-directory: build
+ - name: cache third party build
+ id: cache-third-party
+ uses: actions/cache@v2
+ with:
+ path: ${{ github.workspace }}/build/third_party
+ key: third-party-build-v1.0
- name: build
run: make -j3
working-directory: build
diff --git a/third_party/CMakeLists.txt b/third_party/CMakeLists.txt
index ccd8389..0c6af06 100644
--- a/third_party/CMakeLists.txt
+++ b/third_party/CMakeLists.txt
@@ -2,5 +2,8 @@ add_library(popl INTERFACE)
target_include_directories(popl SYSTEM INTERFACE ${CMAKE_CURRENT_SOURCE_DIR}/popl/include)
add_subdirectory(imgui-1.77)
-#add_subdirectory(spdlog-1.6.1)
add_subdirectory(googletest-1.10.0)
+add_subdirectory(ORB_SLAM3)
+
+# NOTE(alvin): add back when OpenVSLAM is removed
+# add_subdirectory(spdlog-1.6.1)
diff --git a/third_party/ORB_SLAM3/.gitignore b/third_party/ORB_SLAM3/.gitignore
new file mode 100644
index 0000000..c3d1361
--- /dev/null
+++ b/third_party/ORB_SLAM3/.gitignore
@@ -0,0 +1,49 @@
+CMakeLists.txt.user
+CMakeLists_modified.txt
+
+Examples/RGB-D/rgbd_tum
+
+Examples/Monocular/mono_euroc
+Examples/Monocular/mono_kitti
+Examples/Monocular/mono_tum
+Examples/Monocular/mono_tum_vi
+
+Examples/Stereo/stereo_euroc
+Examples/Stereo/stereo_kitti
+Examples/Stereo/stereo_tum_vi
+
+Examples/Monocular-Inertial/mono_inertial_euroc
+Examples/Monocular-Inertial/mono_inertial_tum_vi
+
+Examples/Stereo-Inertial/stereo_inertial_euroc
+Examples/Stereo-Inertial/stereo_inertial_tum_vi
+
+Examples/ROS/ORB_SLAM3/Mono
+Examples/ROS/ORB_SLAM3/Mono_Inertial
+Examples/ROS/ORB_SLAM3/MonoAR
+Examples/ROS/ORB_SLAM3/RGBD
+Examples/ROS/ORB_SLAM3/Stereo
+Examples/ROS/ORB_SLAM3/Stereo_Inertial
+
+Examples/ROS/ORB_SLAM3/CMakeLists.txt.user
+Examples/ROS/ORB_SLAM3/build/
+
+KeyFrameTrajectory.txt
+CameraTrajectory.txt
+kf_*.txt
+f_*.txt
+Thirdparty/DBoW2/build/
+Thirdparty/DBoW2/lib/
+Thirdparty/g2o/build/
+Thirdparty/g2o/config.h
+Thirdparty/g2o/lib/
+Vocabulary/ORBvoc.txt
+build/
+
+lib/
+
+cmake_modules/
+cmake-build-debug/
+
+*.pyc
+*.osa
diff --git a/third_party/ORB_SLAM3/CMakeLists.txt b/third_party/ORB_SLAM3/CMakeLists.txt
new file mode 100644
index 0000000..09e43a0
--- /dev/null
+++ b/third_party/ORB_SLAM3/CMakeLists.txt
@@ -0,0 +1,120 @@
+cmake_minimum_required(VERSION 2.8)
+project(ORB_SLAM3)
+
+IF(NOT CMAKE_BUILD_TYPE)
+ SET(CMAKE_BUILD_TYPE Release)
+ENDIF()
+
+MESSAGE("Build type: " ${CMAKE_BUILD_TYPE})
+
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -O3")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -O3")
+set(CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE} -march=native")
+set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -march=native")
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+LIST(APPEND CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake_modules)
+
+find_package(OpenCV REQUIRED)
+
+MESSAGE("OPENCV VERSION:")
+MESSAGE(${OpenCV_VERSION})
+
+find_package(Eigen3 3.3 REQUIRED)
+find_package(Pangolin REQUIRED)
+
+add_library(${PROJECT_NAME} SHARED
+src/System.cc
+src/Tracking.cc
+src/LocalMapping.cc
+src/LoopClosing.cc
+src/ORBextractor.cc
+src/ORBmatcher.cc
+src/FrameDrawer.cc
+src/Converter.cc
+src/MapPoint.cc
+src/KeyFrame.cc
+src/Atlas.cc
+src/Map.cc
+src/MapDrawer.cc
+src/Optimizer.cc
+src/PnPsolver.cc
+src/Frame.cc
+src/KeyFrameDatabase.cc
+src/Sim3Solver.cc
+src/Initializer.cc
+src/Viewer.cc
+src/ImuTypes.cc
+src/G2oTypes.cc
+src/CameraModels/Pinhole.cpp
+src/CameraModels/KannalaBrandt8.cpp
+src/OptimizableTypes.cpp
+src/MLPnPsolver.cpp
+include/System.h
+include/Tracking.h
+include/LocalMapping.h
+include/LoopClosing.h
+include/ORBextractor.h
+include/ORBmatcher.h
+include/FrameDrawer.h
+include/Converter.h
+include/MapPoint.h
+include/KeyFrame.h
+include/Atlas.h
+include/Map.h
+include/MapDrawer.h
+include/Optimizer.h
+include/PnPsolver.h
+include/Frame.h
+include/KeyFrameDatabase.h
+include/Sim3Solver.h
+include/Initializer.h
+include/Viewer.h
+include/ImuTypes.h
+include/G2oTypes.h
+include/CameraModels/GeometricCamera.h
+include/CameraModels/Pinhole.h
+include/CameraModels/KannalaBrandt8.h
+include/OptimizableTypes.h
+include/MLPnPsolver.h
+include/TwoViewReconstruction.h
+src/TwoViewReconstruction.cc)
+
+add_subdirectory(Thirdparty/DBoW2)
+add_subdirectory(Thirdparty/g2o)
+
+target_include_directories(${PROJECT_NAME} PUBLIC
+ ${PROJECT_SOURCE_DIR}
+ ${PROJECT_SOURCE_DIR}/include
+ ${PROJECT_SOURCE_DIR}/include/CameraModels
+ ${Pangolin_INCLUDE_DIRS}
+)
+
+
+target_link_libraries(${PROJECT_NAME} PUBLIC
+ ${OpenCV_LIBS}
+ ${Pangolin_LIBRARIES}
+ Eigen3::Eigen
+ DBoW2
+ g2o
+)
+
+target_compile_definitions(${PROJECT_NAME} PRIVATE COMPILEDWITHC11)
+
+target_compile_options(${PROJECT_NAME} PRIVATE
+ -Wno-deprecated-declarations
+ -Wno-deprecated
+ -Wno-dangling-else
+ -Wno-sign-compare
+ -Wno-unused-variable
+ -Wno-unused-but-set-variable
+ -Wno-unused-local-typedefs
+ -Wno-unused-result
+ -Wno-maybe-uninitialized
+ -Wno-conversion-null
+ -Wno-comment
+ -Wno-reorder
+)
+
diff --git a/third_party/ORB_SLAM3/Changelog.md b/third_party/ORB_SLAM3/Changelog.md
new file mode 100644
index 0000000..1d19d80
--- /dev/null
+++ b/third_party/ORB_SLAM3/Changelog.md
@@ -0,0 +1,26 @@
+# ORB-SLAM3
+Details of changes between the different versions.
+
+### V0.3: Beta version, 4 Sep 2020
+
+- RGB-D compatibility, the RGB-D examples had been adapted to the new version.
+
+- Kitti and TUM dataset compatibility, these examples had been adapted to the new version.
+
+- ROS compatibility, It had been updated the old references in the code to work with this version.
+
+- Config file parser, the YAML file contains the session configuration, a wrong parametrization may break the execution without any information to solve it. This version parses the file to read all the fields and give a proper answer if one of the fields have been wrong deffined or don't exist.
+
+- Fixed minor bugs.
+
+
+### V0.2: Beta version, 7 Aug 2020
+Initial release. It has these capabilities:
+
+- Multiple-Maps capabilities, it is able to handle multiple maps in the same session and merge them when a common area is detected with a seamless fussion.
+
+- Inertial sensor, the IMU initialization takes a 2 seconds to achieve a scale error less than 5\% and it is reffined in the next 10 seconds until is around 1\%. Inertial measures are integrated at frame rate to estimate the scale, gravity and velocity in order to improve the visual features detection and make the system robust to temporal occlusions.
+
+- Fisheye sensor, the fisheye sensors are now fully supported in monocular and stereo.
+
+
diff --git a/third_party/ORB_SLAM3/Dependencies.md b/third_party/ORB_SLAM3/Dependencies.md
new file mode 100644
index 0000000..c194d26
--- /dev/null
+++ b/third_party/ORB_SLAM3/Dependencies.md
@@ -0,0 +1,48 @@
+##List of Known Dependencies
+###ORB-SLAM3 version 0.3
+
+In this document we list all the pieces of code included by ORB-SLAM3 and linked libraries which are not property of the authors of ORB-SLAM3.
+
+
+#####Code in **src** and **include** folders
+
+* *ORBextractor.cc*.
+This is a modified version of orb.cpp of OpenCV library. The original code is BSD licensed.
+
+* *PnPsolver.h, PnPsolver.cc*.
+This is a modified version of the epnp.h and epnp.cc of Vincent Lepetit.
+This code can be found in popular BSD licensed computer vision libraries as [OpenCV](https://github.com/Itseez/opencv/blob/master/modules/calib3d/src/epnp.cpp) and [OpenGV](https://github.com/laurentkneip/opengv/blob/master/src/absolute_pose/modules/Epnp.cpp). The original code is FreeBSD.
+
+* *MLPnPsolver.h, MLPnPsolver.cc*.
+This is a modified version of the MLPnP of Steffen Urban from [here](https://github.com/urbste/opengv).
+The original code is BSD licensed.
+
+* Function *ORBmatcher::DescriptorDistance* in *ORBmatcher.cc*.
+The code is from: http://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetParallel.
+The code is in the public domain.
+
+#####Code in Thirdparty folder
+
+* All code in **DBoW2** folder.
+This is a modified version of [DBoW2](https://github.com/dorian3d/DBoW2) and [DLib](https://github.com/dorian3d/DLib) library. All files included are BSD licensed.
+
+* All code in **g2o** folder.
+This is a modified version of [g2o](https://github.com/RainerKuemmerle/g2o). All files included are BSD licensed.
+
+#####Library dependencies
+
+* **Pangolin (visualization and user interface)**.
+[MIT license](https://en.wikipedia.org/wiki/MIT_License).
+
+* **OpenCV**.
+BSD license.
+
+* **Eigen3**.
+For versions greater than 3.1.1 is MPL2, earlier versions are LGPLv3.
+
+* **ROS (Optional, only if you build Examples/ROS)**.
+BSD license. In the manifest.xml the only declared package dependencies are roscpp, tf, sensor_msgs, image_transport, cv_bridge, which are all BSD licensed.
+
+
+
+
diff --git a/third_party/ORB_SLAM3/LICENSE b/third_party/ORB_SLAM3/LICENSE
new file mode 100644
index 0000000..9cecc1d
--- /dev/null
+++ b/third_party/ORB_SLAM3/LICENSE
@@ -0,0 +1,674 @@
+ GNU GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc.
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
+ The GNU General Public License is a free, copyleft license for
+software and other kinds of works.
+
+ The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works. By contrast,
+the GNU General Public License is intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users. We, the Free Software Foundation, use the
+GNU General Public License for most of our software; it applies also to
+any other work released this way by its authors. You can apply it to
+your programs, too.
+
+ When we speak of free software, we are referring to freedom, not
+price. Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
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+
+ To protect your rights, we need to prevent others from denying you
+these rights or asking you to surrender the rights. Therefore, you have
+certain responsibilities if you distribute copies of the software, or if
+you modify it: responsibilities to respect the freedom of others.
+
+ For example, if you distribute copies of such a program, whether
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+ Developers that use the GNU GPL protect your rights with two steps:
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diff --git a/third_party/ORB_SLAM3/README.md b/third_party/ORB_SLAM3/README.md
new file mode 100644
index 0000000..ee177df
--- /dev/null
+++ b/third_party/ORB_SLAM3/README.md
@@ -0,0 +1,213 @@
+# ORB-SLAM3
+
+### V0.3: Beta version, 4 Sep 2020
+**Authors:** Carlos Campos, Richard Elvira, Juan J. Gómez Rodríguez, [José M. M. Montiel](http://webdiis.unizar.es/~josemari/), [Juan D. Tardos](http://webdiis.unizar.es/~jdtardos/).
+
+The [Changelog](https://github.com/UZ-SLAMLab/ORB_SLAM3/Changelog.md) describes the features of each version.
+
+ORB-SLAM3 is the first real-time SLAM library able to perform **Visual, Visual-Inertial and Multi-Map SLAM** with **monocular, stereo and RGB-D** cameras, using **pin-hole and fisheye** lens models. In all sensor configurations, ORB-SLAM3 is as robust as the best systems available in the literature, and significantly more accurate.
+
+We provide examples to run ORB-SLAM3 in the [EuRoC dataset](http://projects.asl.ethz.ch/datasets/doku.php?id=kmavvisualinertialdatasets) using stereo or monocular, with or without IMU, and in the [TUM-VI dataset](https://vision.in.tum.de/data/datasets/visual-inertial-dataset) using fisheye stereo or monocular, with or without IMU. Videos of some example executions can be found at [ORB-SLAM3 channel](https://www.youtube.com/channel/UCXVt-kXG6T95Z4tVaYlU80Q).
+
+This software is based on [ORB-SLAM2](https://github.com/raulmur/ORB_SLAM2) developed by [Raul Mur-Artal](http://webdiis.unizar.es/~raulmur/), [Juan D. Tardos](http://webdiis.unizar.es/~jdtardos/), [J. M. M. Montiel](http://webdiis.unizar.es/~josemari/) and [Dorian Galvez-Lopez](http://doriangalvez.com/) ([DBoW2](https://github.com/dorian3d/DBoW2)).
+
+
+
+### Related Publications:
+
+[ORB-SLAM3] Carlos Campos, Richard Elvira, Juan J. Gómez Rodríguez, José M. M. Montiel and Juan D. Tardós, **ORB-SLAM3: An Accurate Open-Source Library for Visual, Visual-Inertial and Multi-Map SLAM**, Under review. **[PDF](https://arxiv.org/pdf/2007.11898.pdf)**.
+
+[IMU-Initialization] Carlos Campos, J. M. M. Montiel and Juan D. Tardós, **Inertial-Only Optimization for Visual-Inertial Initialization**, *ICRA 2020*. **[PDF](https://arxiv.org/pdf/2003.05766.pdf)**
+
+[ORBSLAM-Atlas] Richard Elvira, J. M. M. Montiel and Juan D. Tardós, **ORBSLAM-Atlas: a robust and accurate multi-map system**, *IROS 2019*. **[PDF](https://arxiv.org/pdf/1908.11585.pdf)**.
+
+[ORBSLAM-VI] Raúl Mur-Artal, and Juan D. Tardós, **Visual-inertial monocular SLAM with map reuse**, IEEE Robotics and Automation Letters, vol. 2 no. 2, pp. 796-803, 2017. **[PDF](https://arxiv.org/pdf/1610.05949.pdf)**.
+
+[Stereo and RGB-D] Raúl Mur-Artal and Juan D. Tardós. **ORB-SLAM2: an Open-Source SLAM System for Monocular, Stereo and RGB-D Cameras**. *IEEE Transactions on Robotics,* vol. 33, no. 5, pp. 1255-1262, 2017. **[PDF](https://arxiv.org/pdf/1610.06475.pdf)**.
+
+[Monocular] Raúl Mur-Artal, José M. M. Montiel and Juan D. Tardós. **ORB-SLAM: A Versatile and Accurate Monocular SLAM System**. *IEEE Transactions on Robotics,* vol. 31, no. 5, pp. 1147-1163, 2015. (**2015 IEEE Transactions on Robotics Best Paper Award**). **[PDF](https://arxiv.org/pdf/1502.00956.pdf)**.
+
+[DBoW2 Place Recognition] Dorian Gálvez-López and Juan D. Tardós. **Bags of Binary Words for Fast Place Recognition in Image Sequences**. *IEEE Transactions on Robotics,* vol. 28, no. 5, pp. 1188-1197, 2012. **[PDF](http://doriangalvez.com/php/dl.php?dlp=GalvezTRO12.pdf)**
+
+# 1. License
+
+ORB-SLAM3 is released under [GPLv3 license](https://github.com/UZ-SLAMLab/ORB_SLAM3/LICENSE). For a list of all code/library dependencies (and associated licenses), please see [Dependencies.md](https://github.com/UZ-SLAMLab/ORB_SLAM3/blob/master/Dependencies.md).
+
+For a closed-source version of ORB-SLAM3 for commercial purposes, please contact the authors: orbslam (at) unizar (dot) es.
+
+If you use ORB-SLAM3 in an academic work, please cite:
+
+ @article{ORBSLAM3_2020,
+ title={{ORB-SLAM3}: An Accurate Open-Source Library for Visual, Visual-Inertial
+ and Multi-Map {SLAM}},
+ author={Campos, Carlos AND Elvira, Richard AND G\´omez, Juan J. AND Montiel,
+ Jos\'e M. M. AND Tard\'os, Juan D.},
+ journal={arXiv preprint arXiv:2007.11898},
+ year={2020}
+ }
+
+# 2. Prerequisites
+We have tested the library in **Ubuntu 16.04** and **18.04**, but it should be easy to compile in other platforms. A powerful computer (e.g. i7) will ensure real-time performance and provide more stable and accurate results.
+
+## C++11 or C++0x Compiler
+We use the new thread and chrono functionalities of C++11.
+
+## Pangolin
+We use [Pangolin](https://github.com/stevenlovegrove/Pangolin) for visualization and user interface. Dowload and install instructions can be found at: https://github.com/stevenlovegrove/Pangolin.
+
+## OpenCV
+We use [OpenCV](http://opencv.org) to manipulate images and features. Dowload and install instructions can be found at: http://opencv.org. **Required at leat 3.0. Tested with OpenCV 3.2.0**.
+
+## Eigen3
+Required by g2o (see below). Download and install instructions can be found at: http://eigen.tuxfamily.org. **Required at least 3.1.0**.
+
+## DBoW2 and g2o (Included in Thirdparty folder)
+We use modified versions of the [DBoW2](https://github.com/dorian3d/DBoW2) library to perform place recognition and [g2o](https://github.com/RainerKuemmerle/g2o) library to perform non-linear optimizations. Both modified libraries (which are BSD) are included in the *Thirdparty* folder.
+
+## Python
+Required to calculate the alignment of the trajectory with the ground truth. **Required Numpy module**.
+
+* (win) http://www.python.org/downloads/windows
+* (deb) `sudo apt install libpython2.7-dev`
+* (mac) preinstalled with osx
+
+## ROS (optional)
+
+We provide some examples to process input of a monocular, monocular-inertial, stereo, stereo-inertial or RGB-D camera using ROS. Building these examples is optional. These have been tested with ROS Melodic under Ubuntu 18.04.
+
+# 3. Building ORB-SLAM3 library and examples
+
+Clone the repository:
+```
+git clone https://github.com/UZ-SLAMLab/ORB_SLAM3.git ORB_SLAM3
+```
+
+We provide a script `build.sh` to build the *Thirdparty* libraries and *ORB-SLAM3*. Please make sure you have installed all required dependencies (see section 2). Execute:
+```
+cd ORB_SLAM3
+chmod +x build.sh
+./build.sh
+```
+
+This will create **libORB_SLAM3.so** at *lib* folder and the executables in *Examples* folder.
+
+# 4. EuRoC Examples
+[EuRoC dataset](http://projects.asl.ethz.ch/datasets/doku.php?id=kmavvisualinertialdatasets) was recorded with two pinhole cameras and an inertial sensor. We provide an example script to launch EuRoC sequences in all the sensor configurations.
+
+1. Download a sequence (ASL format) from http://projects.asl.ethz.ch/datasets/doku.php?id=kmavvisualinertialdatasets
+
+2. Open the script "euroc_examples.sh" in the root of the project. Change **pathDatasetEuroc** variable to point to the directory where the dataset has been uncompressed.
+
+3. Execute the following script to process all the sequences with all sensor configurations:
+```
+./euroc_examples
+```
+
+## Evaluation
+EuRoC provides ground truth for each sequence in the IMU body reference. As pure visual executions report trajectories centered in the left camera, we provide in the "evaluation" folder the transformation of the ground truth to the left camera reference. Visual-inertial trajectories use the ground truth from the dataset.
+
+Execute the following script to process sequences and compute the RMS ATE:
+```
+./euroc_eval_examples
+```
+
+# 5. TUM-VI Examples
+[TUM-VI dataset](https://vision.in.tum.de/data/datasets/visual-inertial-dataset) was recorded with two fisheye cameras and an inertial sensor.
+
+1. Download a sequence from https://vision.in.tum.de/data/datasets/visual-inertial-dataset and uncompress it.
+
+2. Open the script "tum_vi_examples.sh" in the root of the project. Change **pathDatasetTUM_VI** variable to point to the directory where the dataset has been uncompressed.
+
+3. Execute the following script to process all the sequences with all sensor configurations:
+```
+./tum_vi_examples
+```
+
+## Evaluation
+In TUM-VI ground truth is only available in the room where all sequences start and end. As a result the error measures the drift at the end of the sequence.
+
+Execute the following script to process sequences and compute the RMS ATE:
+```
+./tum_vi_eval_examples
+```
+
+# 6. ROS Examples
+
+### Building the nodes for mono, mono-inertial, stereo, stereo-inertial and RGB-D
+Tested with ROS Melodic and ubuntu 18.04.
+
+1. Add the path including *Examples/ROS/ORB_SLAM3* to the ROS_PACKAGE_PATH environment variable. Open .bashrc file:
+ ```
+ gedit ~/.bashrc
+ ```
+and add at the end the following line. Replace PATH by the folder where you cloned ORB_SLAM3:
+
+ ```
+ export ROS_PACKAGE_PATH=${ROS_PACKAGE_PATH}:PATH/ORB_SLAM3/Examples/ROS
+ ```
+
+2. Execute `build_ros.sh` script:
+
+ ```
+ chmod +x build_ros.sh
+ ./build_ros.sh
+ ```
+
+### Running Monocular Node
+For a monocular input from topic `/camera/image_raw` run node ORB_SLAM3/Mono. You will need to provide the vocabulary file and a settings file. See the monocular examples above.
+
+ ```
+ rosrun ORB_SLAM3 Mono PATH_TO_VOCABULARY PATH_TO_SETTINGS_FILE
+ ```
+
+### Running Monocular-Inertial Node
+For a monocular input from topic `/camera/image_raw` and an inertial input from topic `/imu`, run node ORB_SLAM3/Mono_Inertial. Setting the optional third argument to true will apply CLAHE equalization to images (Mainly for TUM-VI dataset).
+
+ ```
+ rosrun ORB_SLAM3 Mono PATH_TO_VOCABULARY PATH_TO_SETTINGS_FILE [EQUALIZATION]
+ ```
+
+### Running Stereo Node
+For a stereo input from topic `/camera/left/image_raw` and `/camera/right/image_raw` run node ORB_SLAM3/Stereo. You will need to provide the vocabulary file and a settings file. For Pinhole camera model, if you **provide rectification matrices** (see Examples/Stereo/EuRoC.yaml example), the node will recitify the images online, **otherwise images must be pre-rectified**. For FishEye camera model, rectification is not required since system works with original images:
+
+ ```
+ rosrun ORB_SLAM3 Stereo PATH_TO_VOCABULARY PATH_TO_SETTINGS_FILE ONLINE_RECTIFICATION
+ ```
+
+### Running Stereo-Inertial Node
+For a stereo input from topics `/camera/left/image_raw` and `/camera/right/image_raw`, and an inertial input from topic `/imu`, run node ORB_SLAM3/Stereo_Inertial. You will need to provide the vocabulary file and a settings file, including rectification matrices if required in a similar way to Stereo case:
+
+ ```
+ rosrun ORB_SLAM3 Stereo_Inertial PATH_TO_VOCABULARY PATH_TO_SETTINGS_FILE ONLINE_RECTIFICATION [EQUALIZATION]
+ ```
+
+### Running RGB_D Node
+For an RGB-D input from topics `/camera/rgb/image_raw` and `/camera/depth_registered/image_raw`, run node ORB_SLAM3/RGBD. You will need to provide the vocabulary file and a settings file. See the RGB-D example above.
+
+ ```
+ rosrun ORB_SLAM3 RGBD PATH_TO_VOCABULARY PATH_TO_SETTINGS_FILE
+ ```
+
+**Running ROS example:** Download a rosbag (e.g. V1_02_medium.bag) from the EuRoC dataset (http://projects.asl.ethz.ch/datasets/doku.php?id=kmavvisualinertialdatasets). Open 3 tabs on the terminal and run the following command at each tab for a Stereo-Inertial configuration:
+ ```
+ roscore
+ ```
+
+ ```
+ rosrun ORB_SLAM3 Stereo_Inertial Vocabulary/ORBvoc.txt Examples/Stereo-Inertial/EuRoC.yaml true
+ ```
+
+ ```
+ rosbag play --pause V1_02_medium.bag /cam0/image_raw:=/camera/left/image_raw /cam1/image_raw:=/camera/right/image_raw /imu0:=/imu
+ ```
+
+Once ORB-SLAM3 has loaded the vocabulary, press space in the rosbag tab.
+
+**Remark:** For rosbags from TUM-VI dataset, some play issue may appear due to chunk size. One possible solution is to rebag them with the default chunk size, for example:
+ ```
+ rosrun rosbag fastrebag.py dataset-room1_512_16.bag dataset-room1_512_16_small_chunks.bag
+ ```
+
+
+
diff --git a/third_party/ORB_SLAM3/Thirdparty/DBoW2/CMakeLists.txt b/third_party/ORB_SLAM3/Thirdparty/DBoW2/CMakeLists.txt
new file mode 100644
index 0000000..db38ee5
--- /dev/null
+++ b/third_party/ORB_SLAM3/Thirdparty/DBoW2/CMakeLists.txt
@@ -0,0 +1,31 @@
+cmake_minimum_required(VERSION 2.8)
+project(DBoW2)
+
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -O3 -march=native ")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -O3 -march=native")
+
+set(HDRS_DBOW2
+ DBoW2/BowVector.h
+ DBoW2/FORB.h
+ DBoW2/FClass.h
+ DBoW2/FeatureVector.h
+ DBoW2/ScoringObject.h
+ DBoW2/TemplatedVocabulary.h)
+set(SRCS_DBOW2
+ DBoW2/BowVector.cpp
+ DBoW2/FORB.cpp
+ DBoW2/FeatureVector.cpp
+ DBoW2/ScoringObject.cpp)
+
+set(HDRS_DUTILS
+ DUtils/Random.h
+ DUtils/Timestamp.h)
+set(SRCS_DUTILS
+ DUtils/Random.cpp
+ DUtils/Timestamp.cpp)
+
+find_package(OpenCV REQUIRED)
+
+add_library(DBoW2 SHARED ${SRCS_DBOW2} ${SRCS_DUTILS})
+target_link_libraries(DBoW2 ${OpenCV_LIBS})
+
diff --git a/third_party/ORB_SLAM3/Thirdparty/DBoW2/DBoW2/BowVector.cpp b/third_party/ORB_SLAM3/Thirdparty/DBoW2/DBoW2/BowVector.cpp
new file mode 100644
index 0000000..1337fa3
--- /dev/null
+++ b/third_party/ORB_SLAM3/Thirdparty/DBoW2/DBoW2/BowVector.cpp
@@ -0,0 +1,130 @@
+/**
+ * File: BowVector.cpp
+ * Date: March 2011
+ * Author: Dorian Galvez-Lopez
+ * Description: bag of words vector
+ * License: see the LICENSE.txt file
+ *
+ */
+
+#include
+#include
+#include
+#include
+#include
+
+#include "BowVector.h"
+
+namespace DBoW2 {
+
+// --------------------------------------------------------------------------
+
+BowVector::BowVector(void)
+{
+}
+
+// --------------------------------------------------------------------------
+
+BowVector::~BowVector(void)
+{
+}
+
+// --------------------------------------------------------------------------
+
+void BowVector::addWeight(WordId id, WordValue v)
+{
+ BowVector::iterator vit = this->lower_bound(id);
+
+ if(vit != this->end() && !(this->key_comp()(id, vit->first)))
+ {
+ vit->second += v;
+ }
+ else
+ {
+ this->insert(vit, BowVector::value_type(id, v));
+ }
+}
+
+// --------------------------------------------------------------------------
+
+void BowVector::addIfNotExist(WordId id, WordValue v)
+{
+ BowVector::iterator vit = this->lower_bound(id);
+
+ if(vit == this->end() || (this->key_comp()(id, vit->first)))
+ {
+ this->insert(vit, BowVector::value_type(id, v));
+ }
+}
+
+// --------------------------------------------------------------------------
+
+void BowVector::normalize(LNorm norm_type)
+{
+ double norm = 0.0;
+ BowVector::iterator it;
+
+ if(norm_type == DBoW2::L1)
+ {
+ for(it = begin(); it != end(); ++it)
+ norm += fabs(it->second);
+ }
+ else
+ {
+ for(it = begin(); it != end(); ++it)
+ norm += it->second * it->second;
+ norm = sqrt(norm);
+ }
+
+ if(norm > 0.0)
+ {
+ for(it = begin(); it != end(); ++it)
+ it->second /= norm;
+ }
+}
+
+// --------------------------------------------------------------------------
+
+std::ostream& operator<< (std::ostream &out, const BowVector &v)
+{
+ BowVector::const_iterator vit;
+ std::vector::const_iterator iit;
+ unsigned int i = 0;
+ const unsigned int N = v.size();
+ for(vit = v.begin(); vit != v.end(); ++vit, ++i)
+ {
+ out << "<" << vit->first << ", " << vit->second << ">";
+
+ if(i < N-1) out << ", ";
+ }
+ return out;
+}
+
+// --------------------------------------------------------------------------
+
+void BowVector::saveM(const std::string &filename, size_t W) const
+{
+ std::fstream f(filename.c_str(), std::ios::out);
+
+ WordId last = 0;
+ BowVector::const_iterator bit;
+ for(bit = this->begin(); bit != this->end(); ++bit)
+ {
+ for(; last < bit->first; ++last)
+ {
+ f << "0 ";
+ }
+ f << bit->second << " ";
+
+ last = bit->first + 1;
+ }
+ for(; last < (WordId)W; ++last)
+ f << "0 ";
+
+ f.close();
+}
+
+// --------------------------------------------------------------------------
+
+} // namespace DBoW2
+
diff --git a/third_party/ORB_SLAM3/Thirdparty/DBoW2/DBoW2/BowVector.h b/third_party/ORB_SLAM3/Thirdparty/DBoW2/DBoW2/BowVector.h
new file mode 100644
index 0000000..a7a12a9
--- /dev/null
+++ b/third_party/ORB_SLAM3/Thirdparty/DBoW2/DBoW2/BowVector.h
@@ -0,0 +1,119 @@
+/**
+ * File: BowVector.h
+ * Date: March 2011
+ * Author: Dorian Galvez-Lopez
+ * Description: bag of words vector
+ * License: see the LICENSE.txt file
+ *
+ */
+
+#ifndef __D_T_BOW_VECTOR__
+#define __D_T_BOW_VECTOR__
+
+#include
+#include