jetson xavier nx安装opencv3.4

jetson xavier nx自带的opencv版本是4.1，有的时候，我们需要3.x版本的opencv，这时候就需要我们自己编译opencv。
脚本如下：

set -e

folder=${HOME}/src
mkdir -p $folder

echo "** Purge old opencv installation"
sudo apt-get purge -y libopencv*

echo "** Install requirements"
sudo apt-get update
sudo apt-get install -y build-essential make cmake cmake-curses-gui git g++ pkg-config curl
sudo apt-get install -y libavcodec-dev libavformat-dev libavutil-dev libswscale-dev libeigen3-dev libglew-dev libgtk2.0-dev libpostproc-dev
sudo apt-get install -y libtbb2 libtbb-dev libv4l-dev v4l-utils qv4l2 v4l2ucp
sudo apt-get install -y libdc1394-22-dev libxine2-dev libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev
# sudo apt-get install -y libjasper-dev
sudo apt-get install -y libjpeg8-dev libjpeg-turbo8-dev libtiff-dev libpng-dev libjpeg-dev libtiff5-dev
sudo apt-get install -y libxvidcore-dev libx264-dev libgtk-3-dev
sudo apt-get install -y libatlas-base-dev libopenblas-dev liblapack-dev liblapacke-dev gfortran
sudo apt-get install -y qt5-default
sudo apt-get install -y zlib1g-dev libgl1 libglvnd-dev


sudo apt-get install -y python2.7-dev python3.6-dev python3-testresources
rm -f $folder/get-pip.py
wget https://bootstrap.pypa.io/get-pip.py -O $folder/get-pip.py
sudo python3 $folder/get-pip.py
sudo python2 $folder/get-pip.py
sudo pip3 install protobuf
sudo pip2 install protobuf
sudo pip3 install -U numpy matplotlib
sudo pip2 install -U numpy matplotlib

if [ ! -f /usr/local/cuda/include/cuda_gl_interop.h.bak ]; then
  sudo cp /usr/local/cuda/include/cuda_gl_interop.h /usr/local/cuda/include/cuda_gl_interop.h.bak
fi
sudo patch -N /usr/local/cuda/include/cuda_gl_interop.h < opencv/cuda_gl_interop.h.patch && echo "** '/usr/local/cuda/include/cuda_gl_interop.h' appears to be patched already.  Continue..."

echo "** Download opencv-3.4.0"
cd $folder
if [ ! -f opencv-3.4.0.zip ]; then
  wget https://github.com/opencv/opencv/archive/3.4.0.zip -O opencv-3.4.0.zip
fi
if [ -d opencv-3.4.0 ]; then
  echo "** ERROR: opencv-3.4.0 directory already exists"
  exit
fi
unzip opencv-3.4.0.zip 
cd opencv-3.4.0/

echo "** Building opencv..."
mkdir build
mkdir -p build/install
cd build/

cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=install -D WITH_CUDA=ON -D CUDA_ARCH_BIN="7.2" -D CUDA_ARCH_PTX="" -D WITH_CUBLAS=ON -D ENABLE_FAST_MATH=ON -D CUDA_FAST_MATH=ON -D ENABLE_NEON=ON -D WITH_GSTREAMER=ON -D WITH_LIBV4L=ON -D BUILD_opencv_python2=ON -D BUILD_opencv_python3=ON -D BUILD_TESTS=OFF -D BUILD_PERF_TESTS=OFF -D BUILD_EXAMPLES=OFF -D WITH_QT=ON -D WITH_OPENGL=ON -D CUDA_NVCC_FLAGS="--expt-relaxed-constexpr" -D WITH_TBB=ON  ..
make -j8
sudo make install
sudo ldconfig

python3 -c 'import cv2; print("python3 cv2 version: %s" % cv2.__version__)'
python2 -c 'import cv2; print("python2 cv2 version: %s" % cv2.__version__)'

echo "** Install opencv-3.4.0 successfully"

可以使用参数 -D CMAKE_INSTALL_PREFIX指定安装路径，我这里不把opencv安装在/usr/locla目录下，防止和系统的opencv发生冲突。安装在build/install目录下

使用的时候，我们手动指定opencv的查找路径即可。在CMakeLists.txt中添加下面的语句：

FIND_PACKAGE(OpenCV REQUIRED)
set(CMAKE_PREFIX_PATH "你的opencv安装路径")

参考链接：
https://www.programmersought.com/article/14863019134/
https://www.jetsonhacks.com/2018/11/08/build-opencv-3-4-on-nvidia-jetson-agx-xavier-developer-kit/