How to install opencv in MacOS

1. download opencv and opencv_contrib

#wget https://github.com/opencv/opencv/archive/3.4.0.zip

#wget https://github.com/opencv/opencv_contrib/archive/3.4.0.zip

2.

# cd opencv-3.4.0

#mkdir build

#cd build

# cmake -D CMAKE_BUILD_TYPE=RELEASE  -D  PYTHON_EXECUTABLE=/usr/local/bin/python3.6 -D OPENCV_EXTRA_MODULES_PATH=/tmp_files/opencv_contrib-3.4.0/modules ..

cd opencv-3.4.0
mkdir build
cd build
cmake -D CMAKE_BUILD_TYPE=RELEASE
-D CMAKE_INSTALL_PREFIX=/usr/local
-D INSTALL_PYTHON_EXAMPLES=OFF
-D CMAKE_CXX_COMPILER=/usr/bin/g++
-D INSTALL_C_EXAMPLES=OFF
-D OPENCV_EXTRA_MODULES_PATH=/YourPath/opencv_contrib-3.4.0/modules
-D PYTHON_EXECUTABLE=/usr/bin/python3.6
-D WITH_FFMPEG=OFF
-D BUILD_OPENCV_APPS=OFF
-D BUILD_OPENCD_TS=OFF
-D WITH_LIBV4L=OFF
-D WITH_CUDA=OFF
-D WITH_V4L=ON
-D WITH_QT=ON
-D WITH_LAPACK=OFF
-D WITH_OPENCV_BIOINSPIRED=OFF
-D WITH_XFEATURES2D=ON
-D WITH_OPENCL=OFF
-D WITH_FACE=ON
-D ENABLE_PRECOMPILED_HEADERS=ON
-D WITH_OPENCL=OFF
-D WITH_OPENCL_SVM=OFF
-D WITH_OPENCLAMDFFT=OFF
-D WITH_OPENCLAMDBLAS=OFF
-D WITH_OPENCV_DNN=OFF
-D BUILD_OPENCV_APPS=ON
-D BUILD_EXAMPLES=OFF ..