MacOS系统VSCode中C++环境配置OpenCV及头文件引用问题

一、确认OpenCV安装路径 #

• Homebrew安装的OpenCV，默认路径一般为/usr/local/Cellar/opencv/4.5.5/include/opencv4
• 手动下载框架包安装的，路径是/Library/Frameworks/opencv2.framework/Headers
  （如果不确定路径，Homebrew安装的可以用brew info opencv命令查询）

二、正确的头文件引用 #

不管哪种安装方式，标准引用写法是：

#include <opencv2/opencv.hpp>

不需要添加opencv2.framework或Headers这类前缀，只要VSCode能定位到头文件路径即可。

三、配置VSCode的c_cpp_properties.json #

1. 按Cmd+Shift+P，输入C/C++: Edit Configurations (JSON)打开配置文件
2. 在includePath中添加OpenCV的头文件路径，示例配置如下：

   {
       "configurations": [
           {
               "name": "Mac",
               "includePath": [
                   "${workspaceFolder}/**",
                   "/usr/local/Cellar/opencv/4.5.5/include/opencv4/**"
               ],
               "defines": [],
               "macFrameworkPath": ["/Library/Frameworks"],
               "compilerPath": "/usr/bin/clang++",
               "cStandard": "c17",
               "cppStandard": "c++17",
               "intelliSenseMode": "macos-clang-x64"
           }
       ],
       "version": 4
   }
   

   框架安装的话，把includePath里的Homebrew路径替换为"/Library/Frameworks/opencv2.framework/Headers/**"

四、配置tasks.json实现编译链接 #

1. 按Cmd+Shift+P，输入Tasks: Configure Task，选择C/C++: clang++ build active file
2. 修改args参数，添加OpenCV的链接依赖，示例配置如下：

   {
       "version": "2.0.0",
       "tasks": [
           {
               "type": "cppbuild",
               "label": "C/C++: clang++ build active file",
               "command": "/usr/bin/clang++",
               "args": [
                   "-std=c++17",
                   "-stdlib=libc++",
                   "-g",
                   "${file}",
                   "-o",
                   "${fileDirname}/${fileBasenameNoExtension}",
                   "-I/usr/local/Cellar/opencv/4.5.5/include/opencv4",
                   "-L/usr/local/Cellar/opencv/4.5.5/lib",
                   "-lopencv_core",
                   "-lopencv_highgui",
                   "-lopencv_imgcodecs"
               ],
               "options": {
                   "cwd": "${fileDirname}"
               },
               "problemMatcher": ["$gcc"],
               "group": {
                   "kind": "build",
                   "isDefault": true
               },
               "detail": "编译器: /usr/bin/clang++"
           }
       ]
   }
   

   框架安装的话，把args里的-I...和-L...替换为-framework opencv2即可。

五、测试配置有效性 #

写一段简单代码验证：

#include <opencv2/opencv.hpp>

int main() {
    cv::Mat img = cv::imread("test.jpg");
    if (img.empty()) {
        std::cout << "无法读取图片" << std::endl;
        return -1;
    }
    cv::imshow("Test", img);
    cv::waitKey(0);
    return 0;
}

编译运行后能正常显示图片，说明配置成功。

内容的提问来源于stack exchange，提问作者jonathansl