Commands

Error: Command '['/home/pi/.virtualenvs/cv2_env/bin/python3', '-Im', 'ensurepip', '--upgrade', '--default-pip']' returned non-zero exit status 1.

sudo apt install python3.7 python3-venv python3.7-venv

mkdir build
cd build
cmake -D CMAKE_BUILD_TYPE=RELEASE \
 -D CMAKE_INSTALL_PREFIX=/usr/local \
 -D INSTALL_PYTHON_EXAMPLES=ON \
 -D OPENCV_EXTRA_MODULES_PATH=~/opencv_contrib-4.1.0/modules \
 -D BUILD_EXAMPLES=ON ..

cmake -D CMAKE_BUILD_TYPE=RELEASE \
            -D CMAKE_INSTALL_PREFIX=$cwd/installation/OpenCV-"$cvVersion" \
            -D INSTALL_C_EXAMPLES=ON \
            -D INSTALL_PYTHON_EXAMPLES=ON \
            -D WITH_TBB=ON \
            -D WITH_V4L=ON \
            -D OPENCV_PYTHON3_INSTALL_PATH=$cwd/OpenCV-$cvVersion-py3/lib/python3.5/site-packages \
        -D WITH_QT=ON \
        -D WITH_OPENGL=ON \
        -D OPENCV_EXTRA_MODULES_PATH=../../opencv_contrib/modules \
        -D BUILD_EXAMPLES=ON ..
sudo make install && sudo ldconfig

sudo apt-get install python3.4-dev python3-numpy

sudo apt-get install libblas-dev
sudo apt-get install liblapack-dev
sudo apt-get install python3-dev
sudo apt-get install libatlas-base-dev
sudo apt-get install gfortran
sudo apt-get install python3-setuptools
sudo apt-get install python3-scipy
sudo apt-get update
sudo apt-get install python3-h5py
sudo pip3 install keras

ImportError: No module named yad2k.models.keras_yolo

ValueError: bad marshal data (unknown type code)

sudo apt-get install python-numpy python-scipy python-matplotlib ipython ipython-notebook python-pandas python-sympy python-nose

sudo apt-get -y install libgtk2.0-dev libgtk-3-dev

If you are on Ubuntu or Debian, install libgtk2.0-dev and pkg-config, then re-run cmake or configure script) in cvDestroyAllWindows