根據項目需要，安裝opencv並提供給開發使用，並且使用opencv提供python3的API接口。雖然不知道是個啥，還是簡單了解下。
opencv是什么？
OpenCV的全稱是Open Source Computer Vision Library，是一個跨平台的計算機視覺庫。OpenCV是由英特爾公司發起並參與開發，以BSD許可證授權發行，可以在商業和研究領域中免費使用。OpenCV可用於開發實時的圖像處理、計算機視覺以及模式識別程序。該程序庫也可以使用英特爾公司的IPP(收費庫)進行加速處理。
環境信息：
- opencv-3.4.4 //3.x版本以上建議使用7系列來安裝，省掉超多升級步驟
- opencv_contrib-3.4.4 //opencv3以后 SIFT 和 SURF 之類的屬性被移到了 contrib 中
- centos7
- gcc 4.8.x
- cmake 2.8.x
- pyenv //shell腳本編寫的python版本管理工具
- pyenv-virtualenv //虛擬環境
- python 3.x //使用opencv提供的python3的API接口
一、下載源碼包
- opencv https://github.com/opencv/opencv
- opencv_contrib https://github.com/opencv/opencv_contrib
- python 3.4.1 https://www.python.org/ftp/python/3.4.1/Python-3.4.1.tar.xz
- pyenv https://github.com/pyenv/pyenv
- pyenv-virtualenv https://github.com/pyenv/pyenv-virtualenv
二、安裝python環境
-
安裝pyenv
注:pyenv和python環境安裝可參考：https://www.cnblogs.com/dance-walter/p/9364652.html -
安裝依賴包
//安裝編譯包
~]# yum install -y cmake gcc gcc-c++
//安裝圖形特性功能
]# yum install -y gtk* libdc1394-devel libv4l-devel ffmpeg-devel gstreamer-plugins-base-devel
//安裝圖片功能
]# yum install -y libpng-devel libjpeg-turbo-devel jasper-devel openexr-devel libtiff-devel libwebp-devel
三、安裝python依賴庫
~]# pyenv virtualenv 3.4.1 opencv //創建一個opencv別名的python3.4.1版本的環境
~]# pyenv activate opencv //切換至虛擬opencv環境中
(opencv) ~]# pip install numpy==1.13.1 //根據項目需要選擇性安裝
(opencv) ~]# pip install dlib==19.9.0
(opencv) ~]# pip install scipy==0.18.0
四、編譯安裝opencv
在linux下安裝gtk-devel時會引入安裝python2的安裝，導致在使用cmake時會檢測到兩個python版本，而cmake會傾向於使用低版本的python2。
錯誤過程
(opencv) ~]# tar xf opencv-3.4.4.tar.gz -C /usr/local/pkg/
(opencv) ~]# tar xf opencv_contrib-3.4.4.tar.gz -C /usr/local/pkg/
(opencv) ~]# cd /usr/local/pkg/
(opencv) ~]# mkdir opencv-3.4.4/build //創建build編譯目錄
(opencv) ~]# cd opencv-3.4.4/build
(opencv) ~]# cmake -D CMAKE_BUILD_TYPE=RELEASE \
-D INSTALL_PYTHON_EXAMPLES=ON \
-D OPENCV_EXTRA_MODULES_PATH=/usr/local/pkg/opencv_contrib-3.4.4/modules ..
....
-- The CXX compiler identification is GNU 4.8.5
-- The C compiler identification is GNU 4.8.5
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Performing Test HAVE_CXX11 (check file: cmake/checks/cxx11.cpp)
-- Performing Test HAVE_CXX11 - Failed
**-- Found PythonInterp: /usr/bin/python2.7 (found suitable version "2.7.5", minimum required is "2.7")
-- Found PythonLibs: /lib64/libpython2.7.so (found suitable exact version "2.7.5")** //這里已經查找到相應的環境信息
Traceback (most recent call last):
File "<string>", line 1, in <module>
ImportError: No module named numpy.distutils
**-- Found PythonInterp: /usr/local/python/.pyenv/versions/3.4.1/bin/python (found suitable version "3.4.1", minimum required is "3.2")
-- Could NOT find PythonLibs (missing: PYTHON_LIBRARIES PYTHON_INCLUDE_DIRS) (Required is exact version "3.4.1")**
//這里沒有發現PYTHON_LIBRARIES PYTHON_INCLUDE_DIRS環境信息。需要要在cmake時指定相應信息
....
-- OpenCL: YES (no extra features)
-- Include path: /usr/local/pkg/opencv-3.4.4/3rdparty/include/opencl/1.2
-- Link libraries: Dynamic load
--
**-- Python 2:
-- Interpreter: /usr/bin/python2.7 (ver 2.7.5)
-- Libraries: /lib64/libpython2.7.so (ver 2.7.5)
-- numpy: /usr/lib64/python2.7/site-packages/numpy/core/include (ver 1.13.1)
-- packages path: lib/python2.7/site-packages**
//這不是我想要的，需求是python3
--
-- Python (for build): /usr/bin/python2.7
--
-- Java:
-- ant: NO
-- JNI: /usr/lib/jvm/java/include /usr/lib/jvm/java/include/linux /usr/lib/jvm/java/include
-- Java wrappers: NO
-- Java tests: NO
--
-- Install to: /usr/local
#### 正確過程 ``` ... (opencv) ~]# cmake -D CMAKE_BUILD_TYPE=RELEASE \ -D INSTALL_PYTHON_EXAMPLES=ON \ **-D BUILD_opencv_python3=ON \ -D BUILD_opencv_python2=OFF \** -D PYTHON_EXECUTABLE=$(which python) \ -D PYTHON_INCLUDE_DIR=$(python -c "from distutils.sysconfig import get_python_inc; print(get_python_inc())") \ -D PYTHON_LIBRARY=$(python -c "import distutils.sysconfig as sysconfig; print(sysconfig.get_config_var('LIBDIR'))") \ -D OPENCV_EXTRA_MODULES_PATH=/usr/local/pkg/opencv_contrib-3.4.4/modules .. ... -- OpenCL: YES (no extra features) -- Include path: /usr/local/python/opencv-3.4.4/3rdparty/include/opencl/1.2 -- Link libraries: Dynamic load -- -- Python 3: -- Interpreter: /usr/local/python/.pyenv/shims/python3 (ver 3.4.1) -- Libraries: /usr/local/python/.pyenv/versions/3.4.1/lib (ver 3.4.1) -- numpy: /usr/local/python/.pyenv/versions/3.4.1/lib/python3.4/site-packages/numpy/core/include (ver 1.13.1) -- packages path: lib/python3.4/site-packages -- -- Python (for build): /usr/local/python/.pyenv/shims/python3 -- -- Java: -- ant: NO -- JNI: /usr/lib/jvm/java/include /usr/lib/jvm/java/include/linux /usr/lib/jvm/java/include -- Java wrappers: NO -- Java tests: NO -- -- Install to: /usr/local -- ----------------------------------------------------------------- -- -- Configuring done -- Generating done -- Build files have been written to: /usr/local/python/opencv-3.4.4/build (opencv) ~]# make -j 8 //使用幾個CPU來運，越多速度越快 (opencv) ~]# make install .... -- Set runtime path of "/usr/local/python/cv2/python-3.4/cv2.cpython-34m.so" to "/usr/local/lib64" ... //這時已經安裝好，並且生成了相應.so文件，我們只需把庫文件拷貝到相應python版本的庫目錄下即可 (opencv) ~]# cp -a /usr/local/python/cv2/python-3.4/cv2.cpython-34m.so /usr/local/pkg/.pyenv/versions/3.4.1/lib/python3.4/cv2.so (opencv) ~]# ```
六、測試
(opencv) ~]# python
>>> import cv2
>>> cv2.__version__
'3.4.4'
官方文檔：https://docs.opencv.org/3.4.4/dd/dd5/tutorial_py_setup_in_fedora.html#gsc.tab=0