ubuntu20.04配置VScode + OpenCV

1.前置条件

1. 安装ubuntu20.04的虚拟机

2. 安装完成后：

   sudo apt update
   sudo apt upgrade
   

3. 安装gcc编译器

   sudo apt install build-essential gdb
   

4. 安装cmake

   sudo apt install cmake
   

5. 安装VScode(deb包)，并安装C/C++、C/C++ Extension Pack、C/C++ Themes、CMake、CMake Tools共5个拓展

2.安装opencv

mkdir opencv_build && cd opencv_build

2. 下载opencv
   选择需要的版本，选择tar.gz
   
3. 下载opencv_contrib
   选择需要的版本，选择tar.gz
   
4. 将opencv-4.11.0和opencv_contrib-4.11.0拷贝到opencv_build文件夹，解压

   tar -xzvf opencv-4.11.0.tar.gz
   tar -xzvf opencv_contrib-4.11.0.tar.gz
   cd opencv-4.5.4
   mkdir build && cd build
   

5. 更新一下

   sudo apt update
   

6. 配置编译环境

   sudo apt install libgtk2.0-dev libavcodec-dev libavformat-dev libjpeg-dev libtiff-dev libswscale-dev libpng-dev
   sudo apt install libjasper1 libjasper-dev
   sudo apt install freeglut3-dev libgl1-mesa-dev pkg-config
   sudo apt install libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev libgstreamer-plugins-bad1.0-dev libgstreamer-plugins-good1.0-dev
   sudo apt install gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-bad gstreamer1.0-plugins-ugly gstreamer1.0-tools gstreamer1.0-libav
   sudo apt install gstreamer1.0-doc gstreamer1.0-x gstreamer1.0-alsa gstreamer1.0-gl gstreamer1.0-gtk3 gstreamer1.0-qt5 gstreamer1.0-pulseaudio
   sudo apt install libgtk2.0-dev libgtk-3-dev
   

   解决无法定位 libjasper-dev 的问题：

   sudo apt install vim
   sudo vim /etc/apt/sources.list
   sudo apt update
   

3.编译OpenCV

1. 配置OpenCV编译选项

   cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local -D OPENCV_EXTRA_MODULES_PATH=../../opencv_contrib-4.11.0/modules -D OPENCV_GENERATE_PKGCONFIG=ON -D BUILD_EXAMPLES=OFF -D INSTALL_PYTHON_EXAMPLES=OFF -D INSTALL_C_EXAMPLES=OFF -D WITH_GSTREAMER=ON ..
   

如果出现下载错误

则作地址映射，否则跳过此步
访问：https://tool.chinaz.com/dns/raw.githubusercontent.com
找到访问最快的IPV4地址

sudo vim /etc/hosts
# 例如输入
185.199.109.133	raw.githubusercontent.com

重新编译

2. 编译

   sudo make -j$(nproc)
   sudo make install
   

3. 检查是否安装成功

   pkg-config opencv4 --modversion
   

安装成功

4.开始一个项目进行测试

1. 打开VScode,选择一个文件夹，ctrl + shift + p,输入"quick start"，回车
   
   输入项目名称，如opencvTest，再选择c或者c++,再选择创建可执行文件
   
   选择其他选项部分可不选，直接回车，不用添加新预设
   在CMakeLists.txt中添加如下内容，再ctrl + s保存生成

find_package(OpenCV REQUIRED)
include_directories(${OpenCV_INCLUDE_DIRS})
target_link_libraries(opencvTest ${OpenCV_LIBS})

opencvTest为项目名称

点击左下角生成

退出代码为0，配置成功
写入如下测试代码，若成功显示图像，则大功告成

#include <iostream>
#include <opencv2/opencv.hpp>

int main(int, char**){
    
    cv::Mat src = cv::imread("图片路径");
    cv::namedWindow("input",cv::WINDOW_FREERATIO);
    cv::imshow("input",src);
    
    cv::waitKey(0);
    cv::destroyAllWindows();

    return 0;
}

先生成，再点击左下角运行
效果如下图