OpenCV 3.3.1及Contrib附加库安装教程及问题Undefined reference to cv::xfeatures2d

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# INSTALL OPENCV ON UBUNTU OR DEBIAN #

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# 1. KEEP UBUNTU OR DEBIAN UP TO DATE

sudo apt-get -y update
sudo apt-get -y upgrade
sudo apt-get -y dist-upgrade
sudo apt-get -y autoremove

# 2. INSTALL THE DEPENDENCIES

# Build tools:

sudo apt-get install -y build-essential cmake

# GUI (if you want to use GTK instead of Qt, replace 'qt5-default' with 'libgtkglext1-dev' and remove '-DWITH_QT=ON' option in CMake):

sudo apt-get install -y qt5-default libvtk6-dev

# Media I/O:

sudo apt-get install -y zlib1g-dev libjpeg-dev libwebp-dev libpng-dev libtiff5-dev libjasper-dev libopenexr-dev libgdal-dev

# Video I/O:

sudo apt-get install -y libdc1394-22-dev libavcodec-dev libavformat-dev libswscale-dev libtheora-dev libvorbis-dev libxvidcore-dev libx264-dev yasm libopencore-amrnb-dev libopencore-amrwb-dev libv4l-dev libxine2-dev

# Parallelism and linear algebra libraries:

sudo apt-get install -y libtbb-dev libeigen3-dev

# Python:

sudo apt-get install -y python-dev python-tk python-numpy python3-dev python3-tk python3-numpy

# Java:

sudo apt-get install -y ant default-jdk

# Documentation:

sudo apt-get install -y doxygen

# 3. INSTALL THE LIBRARY (YOU CAN CHANGE '3.3.1' FOR THE LAST STABLE VERSION)

cd ~
sudo apt-get install -y unzip wget

wget https://github.com/opencv/opencv/archive/3.3.1.zip
unzip 3.3.1.zip
rm 3.3.1.zip
mv opencv-3.3.1 OpenCV

cd ~
git clone -b 3.3.1 https://gitee.com/mirrors/opencv_contrib.git
cp -r opencv_contrib OpenCV
#或者
cd ~
git clone https://github.com/opencv/opencv.git
cd ~/opencv
git checkout tags/3.3.1

cd ~/
git clone https://github.com/opencv/opencv_contrib.git
cd ~/opencv_contrib
git checkout tags/3.3.1


cd OpenCV
mkdir build
cd build

cmake -DWITH_QT=ON -DWITH_OPENGL=ON -DFORCE_VTK=ON -DWITH_TBB=ON -DWITH_GDAL=ON -DWITH_XINE=ON -DBUILD_EXAMPLES=OFF -DENABLE_PRECOMPILED_HEADERS=OFF 
OPENCV_EXTRA_MODULES_PATH=/home/xx/OpenCV/opencv_contrib/modules/ ..

make -j4
sudo make -j4 install
sudo ldconfig

使用过程中出现undefined reference to xfeatures2d，说明是链接库的问题

解决办法：全部卸载以后重新安装OpenCV！

sudo make uninstall
sudo apt-get purge libopencv*

cd ~/OpenCV/build
sudo make -j4 install

来源：

https://blog.csdn.net/xiangxianghehe/article/details/78780269

https://gist.github.com/danigosa/367b8a8cbc8d883df80c5c071423e4b2