安装环境 Ubuntu20.04

opencv3

ORB_SLAM3可用opencv3或opencv4编译，作者这里安装测试了opencv3

Step1: 安装opencv的依赖包

sudo apt-get install build-essential
sudo apt-get install cmake git libgtk2.0-dev pkg-config libavcodec-dev libavformat-dev libswscale-dev
sudo apt-get install python-dev python-numpy libtbb2 libtbb-dev libjpeg-dev libpng-dev libtiff-dev libjasper-dev libdc1394-22-dev

• 如果提示找不到libjasper-dev软件包

  sudo apt-add-repository "deb http://security.ubuntu.com/ubuntu xenial-security main"
  sudo apt update
  sudo apt install libjasper1 libjasper-dev

Step2: 下载opencv和opencv_contrib

cd ~/<my_working_directory> # <my_working_directory>替换为你的工作目录
git clone https://github.com/opencv/opencv.git
git clone https://github.com/opencv/opencv_contrib.git
cd opencv
git checkout 3.4.16
cd ..
cd opencv_contrib
git checkout 3.4.16
cd ..

Step3: 编译和安装opencv以及opencv_contrib模块

Step3.1 创建build目录

cd opencv
mkdir build
cd build

Step3.2 执行cmake命令

cmake -D CMAKE_BUILD_TYPE=RELEASE \
      -D CMAKE_INSTALL_PREFIX=/usr/local \
      -D INSTALL_C_EXAMPLES=ON \
      -D INSTALL_PYTHON_EXAMPLES=ON \
      -D WITH_TBB=ON \
      -D WITH_V4L=ON \
      -D WITH_QT=ON \
      -D WITH_OPENGL=ON \
      -D OPENCV_EXTRA_MODULES_PATH=../../opencv_contrib/modules \
      -D BUILD_EXAMPLES=ON ..

Step3.3 编译并安装

# 执行如下命令后获取cpu核心数以加快编译
nproc
# 将nproc得到的数字放在make -j后面，作者的电脑有16的CPU核心
make -j16
sudo make install
sudo sh -c 'echo "/usr/local/lib" >> /etc/ld.so.conf.d/opencv.conf'
sudo ldconfig

• opencv安装参考

• https://docs.opencv.org/3.4.16/d7/d9f/tutorial_linux_install.html
• https://learnopencv.com/install-opencv3-on-ubuntu/
• https://www.codenong.com/cs110289423/

---

Pangolin

• pangolin版本更新到了0.6。此版本编译ORB_SLAM2，ORB_SLAM3，DSO，LDSO等SLAM框架时均会出现问题。
• 解决方法：采用较早版本的pangolin

非常不建议使用最新版本的pangolin进行编译安装，会遇到error: ‘slots_reference’ was not declared in this scope或者cannot findind Eigen3.cmake

issue: https://github.com/raulmur/ORB_SLAM2/issues/1015

Step1: 安装Pangolin的依赖包

sudo port install glew
sudo apt-get install cmake
sudo apt-get install libpython2.7-dev
sudo apt-get install ffmpeg libavcodec-dev libavutil-dev libavformat-dev libswscale-dev
sudo apt-get install libdc1394-22-dev libraw1394-dev
sudo apt-get install libjpeg-dev libpng12-dev libtiff5-dev libopenexr-dev

• libpng12-dev安装可能会报错，但不影响后续步骤。

  Ubuntu16.04之后不支持libpng12-dev 修改为

  sudo apt install libpng-dev

• 这里提供一个较早版本的Pangolin

链接：https://pan.baidu.com/s/17A51BZIq_iJlCvLHUTCH7g

提取码：oitb

• 尽管有人提到了Pangolin v0.5版本可以解决问题，但作者的机器上并没有成功

这里提供了百度网盘的版本

链接：https://pan.baidu.com/s/17A51BZIq_iJlCvLHUTCH7g

提取码：oitb

--来自百度网盘超级会员V5的分享

Step2: 编译并安装Pangolin

cd Pangolin
# 百度网盘的版本有build文件，要先删除再创建
rm -rf build
mkdir build
cd build
cmake ..
# 16替换为你自己电脑的CPU核心数
make -j16
sudo make install

• pangolin安装参考

• https://github.com/stevenlovegrove/Pangolin/tree/v0.5
• https://github.com/raulmur/ORB_SLAM2/issues/1015

---

Step1: 安装ORB_SLAM3的依赖包

sudo apt install libpython2.7-dev

Step2: 下载、编译并安装ORB_SLAM3

git clone https://github.com/UZ-SLAMLab/ORB_SLAM3.git ORB_SLAM3
cd ORB_SLAM3
chmod +x build.sh
# 可以修改 CMakeList.txt 中的`make -j`为`make -j16`来加快编译速度。16替换为你的电脑的CPU核心数
./build.sh

编译ORB_SLAM3常见问题

• ORBSLAM3 fatal error: openssl/md5.h: No such file or directory

• 解决方法：执行如下命令

  sudo apt install libssl-dev

• make[2]: *** [CMakeFiles/ORB_SLAM3.dir/build.make:89: CMakeFiles/ORB_SLAM3.dir/src/LocalMapping.cc.o] Error 1

• 解决方法：在orb_SLAM3/include/CameraModels/KannalaBrandt8.h中添加

  namespace cv
  {
  template static inline Matx<_Tp, m, n> operator/(const Matx<_Tp, m, n>& a, float alpha)
  {
  return Matx<_Tp, m, n>(a, 1.f/alpha, Matx_ScaleOp());
  }
  }

• ORB_SLAM3安装参考

• https://blog.csdn.net/qq_38204686/article/details/114639824
• https://programmerah.com/orb-slam3-compile-error-recipe-for-target-cmakefiles-orb_slam3-dir-src-localmapping-cc-o-failed-39818/