Python与C++ 遍历文件夹下的所有图片实现代码

Python遍历

在之前的数独项目中，进行图像处理的时候用到了遍历文件夹下所有的图片。主要是利用glob模块。glob是python自己带的一个文件操作相关模块，内容不多，可以用它查找符合自己目的的文件。

 # encoding: UTF-8 import glob as gb import cv2   #Returns a list of all folders with participant numbers img_path = gb.glob("numbers\\*.jpg")  for path in img_path:   img = cv2.imread(path)    cv2.imshow('img',img)   cv2.waitKey(1000) 

C++遍历

OpenCV自带一个函数glob()可以遍历文件，如果用这个函数的话，遍历文件也是非常简单的。这个函数非常强大，人脸识别的时候用这个函数应该会比用at.txt更加方便。一个参考示例如下。

#include #include   using namespace std; using namespace cv;   vector read_images_in_folder(cv::String pattern);   int main() {   cv::String pattern = "G:/temp_picture/*.jpg";   vector images = read_images_in_folder(pattern);     return 0;   }   vector read_images_in_folder(cv::String pattern) {   vector fn;   glob(pattern, fn, false);     vector images;   size_t count = fn.size(); //number of png files in images folder   for (size_t i = 0; i < count; i++)   {     images.push_back(imread(fn[i]));     imshow("img", imread(fn[i]));     waitKey(1000);   }   return images; } 

在windows下，没有dirent.h可用，但是可以根据windows.h自己写一个遍历函数。这就有点像是上面的glob的原理和实现了。

#include #include #include  // for windows systems   using namespace std; using namespace cv;   void read_files(std::vector &filepaths,std::vector &filenames, const string &directory);   int main() {   string folder = "G:/temp_picture/";   vector filepaths,filenames;   read_files(filepaths,filenames, folder);   for (size_t i = 0; i < filepaths.size(); ++i)   {     //Mat src = imread(filepaths[i]);     Mat src = imread(folder + filenames[i]);     if (!src.data)       cerr << "Problem loading image!!!" << endl;     imshow(filenames[i], src);     waitKey(1000);   }   return 0;   }   void read_files(std::vector &filepaths, std::vector &filenames, const string &directory) {   HANDLE dir;   WIN32_FIND_DATA file_data;     if ((dir = FindFirstFile((directory + "/*").c_str(), &file_data)) == INVALID_HANDLE_VALUE)     return; /* No files found */     do {     const string file_name = file_data.cFileName;     const string file_path = directory + "/" + file_name;     const bool is_directory = (file_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0;       if (file_name[0] == '.')       continue;       if (is_directory)       continue;       filepaths.push_back(file_path);     filenames.push_back(file_name);   } while (FindNextFile(dir, &file_data));     FindClose(dir); } 

如果电脑上配置了boost库，用boost库来实现这一功能也是比较简洁的。为了用这个我还专门完全编译了Boost。

然而只用到了filesystem。

#include  #include #include   using namespace cv; using namespace std; using namespace boost::filesystem;   void readFilenamesBoost(vector &filenames, const string &folder);   int main() {   string folder = "G:/temp_picture/";   vector filenames;   readFilenamesBoost(filenames, folder);   for (size_t i = 0; i < filenames.size(); ++i)   {     Mat src = imread(folder + filenames[i]);       if (!src.data)       cerr << "Problem loading image!!!" << endl;     imshow("img", src);     waitKey(1000);   }   return 0; }   void readFilenamesBoost(vector &filenames, const string &folder) {   path directory(folder);   directory_iterator itr(directory), end_itr;   string current_file = itr->path().string();     for (; itr != end_itr; ++itr)   {     if (is_regular_file(itr->path()))     {       string filename = itr->path().filename().string(); // returns just filename       filenames.push_back(filename);     }   } }