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| -: | :- |
| Original author | @sajarindider |
| Compatibility | OpenCV >= 3.4 |
The following steps have been tested for macOS (Mavericks) but should work with other versions as well.
This tutorial will assume you have Python, NumPy and Git installed on your machine.
It is recommended to install the latest version of Python 3.x (at least Python 3.8) for compatibility with the latest OpenCV Python bindings.
@note If you have Xcode and Xcode Command Line Tools installed, Git is already available on your machine.
-# Find the version for your system and download CMake from their release's page
-# Install the .dmg package and launch it from Applications. That will give you the UI app of CMake
-# From the CMake app window, choose menu Tools --> How to Install For Command Line Use. Then, follow the instructions from the pop-up there.
-# The install folder will be /usr/local/bin/ by default. Complete the installation by choosing Install command line links.
-# Test that CMake is installed correctly by running:
@code{.bash}
cmake --version
@endcode
@note You can use Homebrew to install CMake with:
@code{.bash}
brew install cmake
@endcode
You can use the latest stable OpenCV version or you can grab the latest snapshot from our Git repository.
Launch Git client and clone OpenCV repository. If you need modules from OpenCV contrib repository then clone it as well.
For example:
@code{.bash}
cd ~/<your_working_directory>
git clone https://github.com/opencv/opencv.git
git clone https://github.com/opencv/opencv_contrib.git
@endcode
-# Create a temporary directory, which we denote as build_opencv, where you want to put
the generated Makefiles, project files as well the object files and output binaries and enter
there.
For example:
@code{.bash}
mkdir build_opencv
cd build_opencv
@endcode
@note It is good practice to keep your source code directories clean. Create the build directory outside of the source tree.
-# Configuring. Run cmake [<some optional parameters>] <path to the OpenCV source directory>
For example:
@code{.bash}
cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_EXAMPLES=ON ../opencv
@endcode
Alternatively, you can use the CMake GUI (`cmake-gui`):
- set the OpenCV source code path to, e.g. `/Users/your_username/opencv`
- set the binary build path to your CMake build directory, e.g. `/Users/your_username/build_opencv`
- set optional parameters
- run: "Configure"
- run: "Generate"
-# Description of some parameters
- build type: `-DCMAKE_BUILD_TYPE=Release` (or `Debug`).
- include Extra Modules: If you cloned the `opencv_contrib` repository and want to include its modules, set:
@code{.bash}
-DOPENCV_EXTRA_MODULES_PATH=../opencv_contrib/modules
@endcode
- set `-DBUILD_DOCS=ON` for building documents (doxygen is required)
- set `-DBUILD_EXAMPLES=ON` to build all examples
-# [optional] Building python. Set the following python parameters:
- `-DPYTHON3_EXECUTABLE=$(which python3)`
- `-DPYTHON3_INCLUDE_DIR=$(python3 -c "from sysconfig import get_paths as gp; print(gp()['include'])")`
- `-DPYTHON3_NUMPY_INCLUDE_DIRS=$(python3 -c "import numpy; print(numpy.get_include())")`
@note
Python 2 has reached its end of life. It is recommended to use Python 3 for building Python bindings.
-# Build. From build directory execute make, it is recommended to do this in several threads
For example:
@code{.bash}
make -j$(sysctl -n hw.ncpu) # runs the build using all available CPU cores
@endcode
-# After building, you can install OpenCV system-wide using:
@code{.bash}
sudo make install
@endcode
-# To use OpenCV in your CMake-based projects through find_package(OpenCV), specify the OpenCV_DIR variable pointing to the build or install directory.
For example:
@code{.bash}
cmake -DOpenCV_DIR=~/build_opencv ..
@endcode
After building (and optionally installing) OpenCV, you can verify the installation by checking the version using Python:
@code{.bash}
python3 -c "import cv2; print(cv2.__version__)"
@endcode
This command should output the version of OpenCV you have installed.
@note You can also use a package manager like Homebrew or pip to install releases of OpenCV only (Not the cutting edge).