learn opencv-Ubuntu安装opencv3

参考：
https://github.com/spmallick/learnopencv

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在这篇文章中，我们将提供在Ubuntu上安装OpenCV 3（C ++和Python）的分步说明。

注意：如果网络环境不好，即使完全按照该教程执行，也可能安装失败的，建议在一个较好的网络环境下安装（因为需要在线下载）

第1步：更新软件包

sudo apt-get updatesudo apt-get upgrade## 注： 如果提示 sudo apt-get update or --fix-missing# 则需执行以下2行命令sudo apt-get updatesudo apt-get upgrade --fix-missing

第2步：安装OS库

步骤2.1：删除以前安装的任何x264

sudo apt-get remove x264 libx264-dev

步骤2.2：安装依赖关系

# 可以将这些命令写入shell脚本中执行sudo apt-get install build-essential checkinstall cmake pkg-config yasm gfortran gitsudo apt-get install libjpeg8-dev libjasper-dev libpng12-dev# If you are using Ubuntu 14.04sudo apt-get install libtiff4-dev# If you are using Ubuntu 16.04sudo apt-get install libtiff5-devsudo apt-get install libavcodec-dev libavformat-dev libswscale-dev libdc1394-22-devsudo apt-get install libxine2-dev libv4l-devsudo apt-get install libgstreamer0.10-dev libgstreamer-plugins-base0.10-devsudo apt-get install libqt4-dev libgtk2.0-dev libtbb-devsudo apt-get install libatlas-base-devsudo apt-get install libfaac-dev libmp3lame-dev libtheora-devsudo apt-get install libvorbis-dev libxvidcore-devsudo apt-get install libopencore-amrnb-dev libopencore-amrwb-devsudo apt-get install x264 v4l-utils

步骤2.3：可选的依赖关系

sudo apt-get install libprotobuf-dev protobuf-compilersudo apt-get install libgoogle-glog-dev libgflags-devsudo apt-get install libgphoto2-dev libeigen3-dev libhdf5-dev doxygen

第3步：安装Python库

sudo apt-get install python-dev python-pip python3-dev python3-pipsudo -H pip2 install -U pip numpysudo -H pip3 install -U pip numpy

我们将使用虚拟环境来安装Python库。 为了将您的项目环境和全球环境分开，通常是一个很好的做法。

# 不想使用虚拟环境 可以跳过该步骤# Install virtual environmentsudo pip2 install virtualenv virtualenvwrappersudo pip3 install virtualenv virtualenvwrapperecho "# Virtual Environment Wrapper"  >> ~/.bashrcecho "source /usr/local/bin/virtualenvwrapper.sh" >> ~/.bashrcsource ~/.bashrc############ For Python 2 ############# create virtual environmentmkvirtualenv facecourse-py2 -p python2workon facecourse-py2# now install python libraries within this virtual environmentpip install numpy scipy matplotlib scikit-image scikit-learn ipython# quit virtual environmentdeactivate################################################## For Python 3 ############# create virtual environmentmkvirtualenv facecourse-py3 -p python3workon facecourse-py3# now install python libraries within this virtual environmentpip install numpy scipy matplotlib scikit-image scikit-learn ipython# quit virtual environmentdeactivate######################################

步骤4：下载OpenCV和OpenCV_contrib

我们将从他们的GitHub仓库下载opencv和opencv_contrib软件包。

步骤4.1：从Github下载opencv

git clone https://github.com/opencv/opencv.git

步骤4.2：从Github下载opencv_contrib

git clone https://github.com/opencv/opencv_contrib.git

第五步：用contrib模块编译并安装OpenCV

步骤5.1：在OpenCV目录下创建一个build目录

cd opencvmkdir buildcd build

步骤5.2：运行CMake

# 如果不支持cuda，移除 -D WITH_CUDA=ON#Remove the line WITH_CUDA=ON if you dont have CUDA in your systemcmake -D CMAKE_BUILD_TYPE=RELEASE \      -D CMAKE_INSTALL_PREFIX=/usr/local \      -D INSTALL_C_EXAMPLES=ON \      -D INSTALL_PYTHON_EXAMPLES=ON \      -D WITH_TBB=ON \      -D WITH_V4L=ON \      -D WITH_QT=ON \      -D WITH_OPENGL=ON \      -D WITH_CUDA=ON \      -D OPENCV_EXTRA_MODULES_PATH=../../opencv_contrib/modules \      -D BUILD_EXAMPLES=ON ..

步骤5.3：编译并安装

# find out number of CPU cores in your machinenproc# substitute 4 by output of nproc# 使用 nproc输出的值代替 4make -j4# 如果报错 执行make -j1sudo make installsudo sh -c 'echo "/usr/local/lib" >> /etc/ld.so.conf.d/opencv.conf'sudo ldconfig

步骤5.4：在虚拟环境中创建符号链接

根据你的Python版本，路径会有所不同。 OpenCV的Python二进制文件（cv2.so）可以安装在目录site-packages或dist-packages中。 使用以下命令找出机器上的正确位置。

find /usr/local/lib/ -type f -name "cv2*.so"

它应该输出类似于其中之一的路径（或者在为Python2和Python3编译OpenCV的情况下输出两个路径：

############ For Python 2 ############## binary installed in dist-packages/usr/local/lib/python2.6/dist-packages/cv2.so/usr/local/lib/python2.7/dist-packages/cv2.so## binary installed in site-packages/usr/local/lib/python2.6/site-packages/cv2.so/usr/local/lib/python2.7/site-packages/cv2.so############ For Python 3 ############## binary installed in dist-packages/usr/local/lib/python3.5/dist-packages/cv2.cpython-35m-x86_64-linux-gnu.so/usr/local/lib/python3.6/dist-packages/cv2.cpython-36m-x86_64-linux-gnu.so## binary installed in site-packages/usr/local/lib/python3.5/site-packages/cv2.cpython-35m-x86_64-linux-gnu.so/usr/local/lib/python3.6/site-packages/cv2.cpython-36m-x86_64-linux-gnu.so

运行以下命令之前，请仔细检查机器上的确切路径

############ For Python 2 ############cd ~/.virtualenvs/facecourse-py2/lib/python2.7/site-packagesln -s /usr/local/lib/python2.7/dist-packages/cv2.so cv2.so############ For Python 3 ############cd ~/.virtualenvs/facecourse-py3/lib/python3.6/site-packagesln -s /usr/local/lib/python3.6/dist-packages/cv2.cpython-36m-x86_64-linux-gnu.so cv2.so

第6步：测试OpenCV3

我们将测试用OpenCV编写的红眼去除器应用程序来测试我们的C ++和Python安装。 下载RedEyeRemover.zip并将其解压缩到一个文件夹中。

步骤6.1：测试C ++代码

在提取的文件夹中移动，编译并运行。

# compile# There are backticks ( ` ) around pkg-config command not single quotesg++ -std=c++11 removeRedEyes.cpp `pkg-config --libs --cflags opencv` -o removeRedEyes# run./removeRedEyes

步骤6.2：测试Python代码

激活Python虚拟环境

############ For Python 2 ############workon facecourse-py2############ For Python 3 ############workon facecourse-py3

快速检查

# open ipython (run this command on terminal)ipython# import cv2 and print version (run following commands in ipython)import cv2print cv2.__version__# If OpenCV3 is installed correctly,above command should give output 3.3.0# Press CTRL+D to exit ipython

运行RedEyeRemover演示

python removeRedEyes.py

现在你可以退出Python的虚拟环境。

deactivate

无论何时您要运行使用OpenCV的Python脚本，您都应该使用workon命令激活我们创建的虚拟环境。