Install OpenCV 3.4.2 on Raspberry Pi Raspbian Stretch

build-opencv.sh

#!/usr/bin/env bash

pushd ~/opencv/opencv-3.4.2
mkdir -p build
pushd build
cmake -D CMAKE_BUILD_TYPE=RELEASE \
      -D CMAKE_INSTALL_PREFIX=/usr/local \
      -D CMAKE_BUILD_TYPE=RELEASE \
      -D OPENCV_EXTRA_MODULES_PATH=../../opencv_contrib-3.4.2/modules \
      -D OPENCV_ENABLE_NONFREE=ON \
      -D BUILD_PERF_TESTS=OFF \
      -D BUILD_TESTS=OFF \
      -D BUILD_DOCS=ON \
      -D BUILD_EXAMPLES=ON \
      -D WITH_TBB=ON \
      -D WITH_OPENMP=ON \
      -D PYTHON3_EXECUTABLE=$(which python2) \
      -D PYTHON_EXECUTABLE=$(which python3) \
      ..
make -j "$(nproc)"
popd; popd

download-opencv.sh

#!/usr/bin/env bash

OPENCV_VERSION=3.4.2
cd ~
mkdir -p opencv && pushd opencv

wget -O "opencv-${OPENCV_VERSION}.tar.gz" "https://github.com/opencv/opencv/archive/${OPENCV_VERSION}.tar.gz"
wget -O "opencv_contrib-${OPENCV_VERSION}.tar.gz" "https://github.com/opencv/opencv_contrib/archive/${OPENCV_VERSION}.tar.gz"
tar -xvf "opencv-${OPENCV_VERSION}.tar.gz"
tar -xvf "opencv_contrib-${OPENCV_VERSION}.tar.gz"
popd

install-deps.sh

#!/usr/bin/env bash

sudo apt-get purge -y wolfram-engine libreoffice*
sudo apt-get clean
sudo apt-get update
sudo apt-get upgrade -y
sudo apt-get dist-upgrade -y
sudo apt-get autoremove -y
# For some reason I couldn't install libgtk2.0-dev or libgtk-3-dev without running the 
# following line
# See https://www.raspberrypi.org/forums/viewtopic.php?p=1254646#p1254665 for issue and resolution
sudo apt-get install -y devscripts debhelper cmake libldap2-dev libgtkmm-3.0-dev libarchive-dev \
                        libcurl4-openssl-dev intltool
sudo apt-get install -y build-essential cmake pkg-config libjpeg-dev libtiff5-dev libjasper-dev \
                        libpng12-dev libavcodec-dev libavformat-dev libswscale-dev libv4l-dev \
                        libxvidcore-dev libx264-dev libgtk2.0-dev libgtk-3-dev \
                        libatlas-base-dev libblas-dev libeigen3-dev liblapack-dev \
                        gfortran python2.7-dev python3-dev
sudo pip2 install -U pip
sudo pip3 install -U pip
sudo pip2 install numpy
sudo pip3 install numpy