My Ubuntu OpenCV Install

test.md

sudo apt install build-essential cmake git pkg-config libgtk-3-dev
libavcodec-dev libavformat-dev libswscale-dev libv4l-dev
libxvidcore-dev libx264-dev libjpeg-dev libpng-dev libtiff-dev
gfortran openexr libatlas-base-dev python3-dev python3-numpy
libtbb2 libtbb-dev libdc1394-22-dev libopenexr-dev
libgstreamer-plugins-base1.0-dev libgstreamer1.0-dev

sudo apt install build-essential cmake pkg-config unzip yasm git checkinstall

sudo apt install libavcodec-dev libavformat-dev libswscale-dev libavresample-dev libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev libxvidcore-dev x264 libx264-dev libfaac-dev libmp3lame-dev libtheora-dev libfaac-dev libmp3lame-dev libvorbis-dev

sudo apt install libopencore-amrnb-dev libopencore-amrwb-dev

sudo apt-get install libdc1394-22 libdc1394-22-dev libxine2-dev libv4l-dev v4l-utilscode

cd /usr/include/linux 
sudo ln -s -f ../libv4l1-videodev.h videodev.h 
cd ~

mkdir ~/opencv_build && cd ~/opencv_build 
git clone https://github.com/opencv/opencv.git 
git clone https://github.com/opencv/opencv_contrib.git

cd ~/opencv_build/opencv 
mkdir -p build && cd build

echo "Create a virtual environtment for the python binding module"
sudo pip install virtualenv virtualenvwrapper
sudo rm -rf ~/.cache/pip
echo "Edit ~/.bashrc"
export WORKON_HOME=$HOME/.virtualenvs
export VIRTUALENVWRAPPER_PYTHON=/usr/bin/python3
source /usr/local/bin/virtualenvwrapper.sh
mkvirtualenv cv -p python3
pip install numpy

cmake -D CMAKE_BUILD_TYPE=RELEASE
-D CMAKE_INSTALL_PREFIX=/usr/local
-D INSTALL_C_EXAMPLES=ON
-D INSTALL_PYTHON_EXAMPLES=ON
-D OPENCV_GENERATE_PKGCONFIG=ON
-D OPENCV_EXTRA_MODULES_PATH=~/opencv_build/opencv_contrib/modules
-D BUILD_EXAMPLES=ON ..

cmake -D CMAKE_BUILD_TYPE=RELEASE \
-D CMAKE_C_COMPILER=/usr/bin/gcc \
-D CMAKE_INSTALL_PREFIX=/usr/local \
-D INSTALL_C_EXAMPLES=ON \
-D INSTALL_PYTHON_EXAMPLES=ON \
-D OPENCV_EXTRA_MODULES_PATH=~/opencv_build/opencv_contrib/modules \
-D BUILD_opencv_cudacodec=OFF \
-D ENABLE_FAST_MATH=1 \
-D CUDA_FAST_MATH=1 \
-D WITH_CUDNN=ON \
-D OPENCV_DNN_CUDA=ON \
-D WITH_CUDA=ON \
-D WITH_CUBLAS=1 \
-D WITH_V4L=ON \
-D WITH_QT=OFF \
-D WITH_OPENGL=ON\
-D WITH_GSTREAMER=ON \
-D WITH_TBB=ON \
-D OPENCV_GENERATE_PKGCONFIG=ON \
-D OPENCV_PC_FILE_NAME=opencv.pc \
-D OPENCV_ENABLE_NONFREE=ON \
-D OPENCV_PYTHON3_INSTALL_PATH=~/.virtualenvs/cv/lib/python3.8/site-packages  \
-D BUILD_EXAMPLES=ON \
-D CUDA_ARCH_BIN=5.0 ..

-D CUDNN_LIBRARY=/usr/lib/x86_64-linux-gnu/libcudnn.so.8.1.1 \
-D CUDNN_INCLUDE_DIR=/usr/local/cuda-11.2/include  \

cmake -D CMAKE_BUILD_TYPE=RELEASE \
	-D CMAKE_C_COMPILER=/usr/bin/gcc \
-D CMAKE_INSTALL_PREFIX=/usr/local \
-D INSTALL_PYTHON_EXAMPLES=ON \
-D INSTALL_C_EXAMPLES=OFF \
-D WITH_TBB=ON \
-D WITH_CUDA=ON \
-D BUILD_opencv_cudacodec=OFF \
-D ENABLE_FAST_MATH=1 \
-D CUDA_FAST_MATH=1 \
-D WITH_CUBLAS=1 \
-D WITH_V4L=ON \
-D WITH_QT=OFF \
-D WITH_OPENGL=ON \
-D WITH_GSTREAMER=ON \
-D OPENCV_GENERATE_PKGCONFIG=ON \
-D OPENCV_PC_FILE_NAME=opencv.pc \
-D OPENCV_ENABLE_NONFREE=ON \
-D OPENCV_PYTHON3_INSTALL_PATH=~/.virtualenvs/cv/lib/python3.8/site-packages \
-D OPENCV_EXTRA_MODULES_PATH=~/opencv_contrib-4.5.1/modules \
-D PYTHON_EXECUTABLE=~/.virtualenvs/cv/bin/python3 \
-D WITH_CUDNN=ON \
-D OPENCV_DNN_CUDA=ON \
-D CUDA_ARCH_BIN=8.6 \
-D BUILD_EXAMPLES=ON ..

nproc
make -j4

sudo make install

sudo make uninstall # use this to clean uninstall

sudo /bin/bash -c 'echo "/usr/local/lib" >> /etc/ld.so.conf.d/opencv.conf'
sudo ldconfig

sudo cp -r ~/.virtualenvs/cv/lib/python3.8/site-packages/cv2 /usr/local/lib/python3.8/dist-packages
echo "Modify config-3.8.py to point to the target directory" 
sudo nano /usr/local/lib/python3.8/dist-packages/cv2/config-3.8.py ``` 
    PYTHON_EXTENSIONS_PATHS = [
    os.path.join('/usr/local/lib/python3.8/dist-packages/cv2', 'python-3.8')
    ] + PYTHON_EXTENSIONS_PATHS

```bash
pkg-config --modversion opencv4

python3 -c "import cv2; print(cv2.__version__)"

/w CUDA

https://medium.com/@sb.jaduniv/how-to-install-opencv-4-2-0-with-cuda-10-1-on-ubuntu-20-04-lts-focal-fossa-bdc034109df3

https://cuda-chen.github.io/image processing/programming/2020/02/22/build-opencv-dnn-module-with-nvidia-gpu-support-on-ubuntu-1804.html

Use -Wno-deprecated-gpu-targets to s

original source : https://gist.github.com/raulqf/f42c718a658cddc16f9df07ecc627be7