1. 安装依赖
opencv中的一些图像、视频相关的功能需要一些依赖，因此在安装opencv之前需要先安装这些依赖；在使用apt安装相关依赖时，会出现无法安装的情况，这时可以用aptitude来降级安装。
| 名称 | apt package 名称 | 功能 |
|---|---|---|
| 编译系统 | build-essential cmake pkg-config | 生成 OpenCV |
| 图像库 | libpng-dev libjpeg-dev | 提供各类图像格式的编解码 |
| OpenBLAS | libopenblas-dev | 利用 CPU 向量运算指令为大量算法提供加速。 |
| Eigen3 | libeigen3-dev | 提供线性代数相关算法支持 |
| Intel TBB | libtbb-dev | 在 Intel CPU 上提供高性能并发计算支持 |
| FFMPEG | libavcodec-dev libavformat-dev libswscale-dev | 提供视频编解码能力 |
| GStreamer | libgstreamer-plugins-base1.0-dev libgstreamer1.0-dev | 提供流媒体处理能力 |
| GTK | libgtk-3-dev libcanberra-gtk-module libcanberra-gtk3-module | 图形化用户界面 |
2. 安装opencv
2.1 从源码安装
参考：在 Linux 系统中编译安装 OpenCV - 知乎
2.2 直接安装
参考： OpenCV 的最简安装方式（Linux） - 知乎
3. 验证
新建一个文件，命名为：test.cc:
#include <iostream>
#include "opencv2/opencv.hpp"
#include "opencv2/imgproc.hpp"
#include "opencv2/highgui.hpp"int main(int argc, char **argv)
{auto img_path = argv[1];cv::Mat img = cv::imread(img_path);if(img.empty()){std::cout<<"----------image read error!--------------"<<std::endl;return 0;}cv::Scalar color;color[0]=0;color[1]=0;color[2]=255;// 红色cv::Rect rec1;rec1=cv::Rect(10,10,500,500);cv::rectangle(img, rec1,color,100,-1,0);cv::imwrite("result.jpg", img);cv::namedWindow("image", cv::WINDOW_NORMAL);cv::imshow("image", img);cv::waitKey(0);// std::count<<img.empty()<<std::endl;std::cout<<"done!"<<std::endl;return 0;
}
编写CMakeLists.txt：
# cmake needs this line
cmake_minimum_required(VERSION 3.1)# Define project name
project(opencv_example_project)# Find OpenCV, you may need to set OpenCV_DIR variable
# to the absolute path to the directory containing OpenCVConfig.cmake file
# via the command line or GUI
find_package(OpenCV REQUIRED)# If the package has been found, several variables will
# be set, you can find the full list with descriptions
# in the OpenCVConfig.cmake file.
# Print some message showing some of them
message(STATUS "OpenCV library status:")
message(STATUS " config: ${OpenCV_DIR}")
message(STATUS " version: ${OpenCV_VERSION}")
message(STATUS " libraries: ${OpenCV_LIBS}")
message(STATUS " include path: ${OpenCV_INCLUDE_DIRS}")# Declare the executable target built from your sources
add_executable(opencv_example test_cv.cc)# Link your application with OpenCV libraries
target_link_libraries(opencv_example PRIVATE ${OpenCV_LIBS})在同级目录下新建build文件夹，并进入，编译，运行：
cd build
cmake ..
make -j8
./opencv_example如果没有报错，则说明安装成功。
若有报错，大部分情况都是因为缺少相应依赖，通过第1步中的方法安装即可。
