安装OpenCV for python3

Question

我遵循了许多如何安装OpenCV的手册/教程，但它们似乎都适用于我的python2.7，而不是我想要的python3.4。我正在学习这教程，但不使用虚拟环境。在制作

$cmake \                                                                                                                  
-D CMAKE_BUILD_TYPE=RELEASE \
-D CMAKE_INSTALL_PREFIX=/usr/local \
-D INSTALL_C_EXAMPLES=OFF \
-D INSTALL_PYTHON_EXAMPLES=ON \
-D OPENCV_EXTRA_MODULES_PATH=../../opencv_contrib/modules \
-D BUILD_EXAMPLES=ON \
-D PYTHON_EXECUTABLE=/usr/bin/python3.4 \
-D PYTHON_PACKAGES_PATHS=/usr/local/lib/python3.4/dist-packages/ \
-D PYTHON_NUMPY_INCLUDE_DIRS=/usr/local/lib/python3.4/dist-packages/numpy/core/include ..

comand it列出了这两个版本：

--   Python 2:
--     Interpreter:                 /usr/bin/python2.7 (ver 3.4.3)
--     Libraries:                   NO
--     numpy:                       /usr/local/lib/python2.7/dist-packages/numpy/core/include (ver 1.10.4)
--     packages path:               lib/python2.7/dist-packages
-- 
--   Python 3:
--     Interpreter:                 /usr/bin/python3.4 (ver 3.4.3)
--     Libraries:                   NO
--     numpy:                       /usr/local/lib/python3.4/dist-packages/numpy/core/include (ver 1.10.4)
--     packages path:               lib/python3.4/dist-packages
-- 
--   Python (for build):            /usr/bin/python2.7

但是省略了python_executable标志，并使用python2.7进行构建(在继续安装之后，我检查了它在python2.7上的工作)。

如何使它使用python3.4进行构建？

我试过的事情：

运行此cmake时：

cmake \
-D CMAKE_BUILD_TYPE=RELEASE \
-D CMAKE_INSTALL_PREFIX=$(python3 -c "import sys; print(sys.prefix)") \
-D PYTHON_EXECUTABLE=$(which python3) ..

它正确地列出了图书馆：

--   Python 2:
--     Interpreter:                 /usr/bin/python2.7 (ver 3.4.3)
--     Libraries:                   NO
--     numpy:                       /usr/local/lib/python2.7/dist-packages/numpy/core/include (ver 1.10.4)
--     packages path:               lib/python2.7/dist-packages
-- 
--   Python 3:
--     Interpreter:                 /usr/bin/python3.4 (ver 3.4.3)
--     Libraries:                   /usr/lib/x86_64-linux-gnu/libpython3.4m.so (ver 3.4.3)
--     numpy:                       /usr/local/lib/python3.4/dist-packages/numpy/core/include (ver 1.10.4)
--     packages path:               lib/python3.4/dist-packages
-- 
--   Python (for build):            /usr/bin/python2.7

但仍然列出了为之建造的python2.7。

相关信息：

$whereis python3                                                                                                          
python3: /usr/bin/python3.4dm-config /usr/bin/python3.4m /usr/bin/python3.4m-config /usr/bin/python3.4-config /usr/bin/python3 /usr/bin/python3.4-dbg-config /usr/bin/python3.4 /usr/bin/python3.4-dbg /usr/bin/python3.4dm /etc/python3 /etc/python3.4 /usr/lib/python3.0 /usr/lib/python3.5 /usr/lib/python3 /usr/lib/python3.4 /usr/lib/python3.2 /usr/lib/python3.1 /usr/lib/python3.3 /usr/bin/X11/python3.4dm-config /usr/bin/X11/python3.4m /usr/bin/X11/python3.4m-config /usr/bin/X11/python3.4-config /usr/bin/X11/python3 /usr/bin/X11/python3.4-dbg-config /usr/bin/X11/python3.4 /usr/bin/X11/python3.4-dbg /usr/bin/X11/python3.4dm /usr/local/lib/python3.4 /usr/include/python3.4m /usr/include/python3.4 /usr/include/python3.4dm /usr/share/python3 /usr/share/man/man1/python3.1.gz

Answer 1

在删除CMakeCache.txt rm CMakeCache.txt之后，我找到了答案，然后重新运行cmake命令：

cmake  \
-D CMAKE_BUILD_TYPE=RELEASE \
-D CMAKE_INSTALL_PREFIX=$(python3 -c "import sys; print(sys.prefix)") \
-D PYTHON_EXECUTABLE=/usr/bin/python3.4 \
-D BUILD_EXAMPLES=ON \
-D INSTALL_C_EXAMPLES=OFF \
-D OPENCV_EXTRA_MODULES_PATH=../../opencv_contrib/modules \
-D INSTALL_PYTHON_EXAMPLES=ON ..

产出如下：

--   Python 2:
--     Interpreter:                 /usr/bin/python3.4 (ver 3.4.3)
--     Libraries:                   /usr/lib/x86_64-linux-gnu/libpython3.4m.so (ver 3.4.3)
--     numpy:                       /usr/local/lib/python3.4/dist-packages/numpy/core/include (ver 1.10.4)
--     packages path:               lib/python3.4/dist-packages
-- 
--   Python 3:
--     Interpreter:                 /usr/bin/python3.4 (ver 3.4.3)
--     Libraries:                   /usr/lib/x86_64-linux-gnu/libpython3.4m.so (ver 3.4.3)
--     numpy:                       /usr/local/lib/python3.4/dist-packages/numpy/core/include (ver 1.10.4)
--     packages path:               lib/python3.4/dist-packages
-- 
--   Python (for build):            /usr/bin/python3.4
-- 

所以我坚持分期付款：

make -j4
sudo make install
sudo ldconfig