OpenCV

OpenCV 教程

http://www.opencv.org.cn/opencvdoc/2.3.2/html/doc/tutorials/tutorials.html#opencv

 

# Installation in Linux

Build core modules

# Install minimal prerequisites (Ubuntu 18.04 as reference)

sudo apt update && sudo apt install -y cmake g++ wget unzip

# Download and unpack sources

wget -O opencv.zip https://github.com/opencv/opencv/archive/master.zip

unzip opencv.zip

# Create build directory

mkdir -p build && cd build

# Configure

cmake ../opencv-master

# Build

cmake --build .

Build with opencv_contrib

# Install minimal prerequisites (Ubuntu 18.04 as reference)

sudo apt update && sudo apt install -y cmake g++ wget unzip

# Download and unpack sources

wget -O opencv.zip https://github.com/opencv/opencv/archive/master.zip

wget -O opencv_contrib.zip https://github.com/opencv/opencv_contrib/archive/master.zip

unzip opencv.zip

unzip opencv_contrib.zip

# Create build directory and switch into it

mkdir -p build && cd build

# Configure

cmake -DOPENCV_EXTRA_MODULES_PATH=../opencv_contrib-master/modules ../opencv-master

# Build

cmake --build .

By default OpenCV will be installed to the /usr/local directory, all files will be copied to following locations:

• /usr/local/bin - executable files
• /usr/local/lib - libraries (.so)
• /usr/local/cmake/opencv4 - cmake package
• /usr/local/include/opencv4 - headers
• /usr/local/share/opencv4 - other files (e.g. trained cascades in XML format)

Since /usr/local is owned by the root user, the installation should be performed with elevated privileges (sudo):

sudo make install

 

Build samples

# C
export C_INCLUDE_PATH=/usr/local/include/opencv4:$C_INCLUDE_PATH
# CPP
export CPLUS_INCLUDE_PATH=/usr/local/include/opencv4:$CPLUS_INCLUDE_PATH

 

cd samples/cpp/example_cmake

mkdir build

cd build

cmake ..

make

 

http://www.opencv.org.cn/opencvdoc/2.3.2/html/doc/tutorials/introduction/linux_install/linux_install.html#linux-installation

https://docs.opencv.org/master/d7/d9f/tutorial_linux_install.html

 

Cross compilation for ARM based Linux systems

https://docs.opencv.org/3.4.13/d0/d76/tutorial_arm_crosscompile_with_cmake.html

 

# 环境变量

【1】include头文件路径
# C
export C_INCLUDE_PATH=XXXX:$C_INCLUDE_PATH
# CPP
export CPLUS_INCLUDE_PATH=XXX:$CPLUS_INCLUDE_PATH

【2】link链接库文件路径
-fPIC -shared
-fPIC -static
链接库文件的搜索路径指定有两种方式：1）修改/etc/so.ld.conf 2）修改环境变量，在其中添加自己的路径

1）在环境变量中添加
动态链接库搜索路径：
export LD_LIBRARY_PATH=XXX:$LD_LIBRARY_PATH
静态链接库搜索路径：
export LIBRARY_PATH=XXX:$LIBRARY_PATH
以上修改可以直接命令行输入（一次性），可以在/etc/profile中完成（对所有用户生效），也可以在用户home目录下的.bashrc或.bash_profile中添加（针对某个用户生效）,修改完后重新登录即生效。

2）在/etc/ld.so.conf 中添加指定的链接库搜索路径（需要root权限），然后运行 /sbin/ldconfig，以达到刷新 /etc/ld.so.cache的效果。

以上两种方式均可以达到指定链接库搜索路径的效果。

 

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海思平台OpenCV编译与进一步裁剪

https://zhuanlan.zhihu.com/p/198457743?utm_source=org.mozilla.firefox_beta