Download opencv and opencv extra modules

1. Clone opencv from public github repo

   git clone https://github.com/opencv/opencv.git
   git clone https://github.com/opencv/opencv_contrib.git
   

2. Checkout release tags of opencv and opencv_contrib

   cd opencv
   git checkout 4.8.1
   cd ../opencv_contrib
   git checkout 4.8.1
   cd ..
   

Configure build

1. Create build dir for opencv

   mkdir opencv_build
   

2. Run CMake with CUDA flags

   cd opencv_build
   

   cmake \
   -D WITH_CUDA=ON \
   -D WITH_CUDNN=ON \
   -D CUDA_ARCH_BIN="8.7" \
   -D CUDA_ARCH_PTX="" \
   -D OPENCV_GENERATE_PKGCONFIG=ON \
   -D OPENCV_EXTRA_MODULES_PATH=../opencv_contrib/modules \
   -D WITH_GSTREAMER=ON \
   -D WITH_LIBV4L=ON \
   -D BUILD_opencv_python3=ON \
   -D BUILD_TESTS=OFF \
   -D BUILD_PERF_TESTS=OFF \
   -D BUILD_EXAMPLES=OFF \
   -D CMAKE_BUILD_TYPE=RELEASE \
   -D CUDA_TOOLKIT_ROOT_DIR=/usr/local/cuda \
   -D CMAKE_INSTALL_PREFIX=/usr/local \
   ../opencv
   

Build and install opencv

1. Start build

   make -j12
   

   NOTE: This step takes quite a while (30mins). If you're accessing the Jetson over SSH, it is recommended to execute this command in a screen instance.

   screen -dmS "opencv" make -j12
   

2. Install opencv

   sudo make install