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#include #include #include #include #include using namespace std;#define PRINT(x) cout<<#x<<": "<< x << endlinline int to_int (const void*data){ unsigned char* ptr = (unsigned char*) data; int result = 0; for (int i = 3; i >= 0; i--) { result += ptr[i] * pow (256, 3 - i); } return result;}int main(){ const string mnist_data_path (R"(F:\libs\caffe\data\mnist\t10k-images-idx3-ubyte)"); const string mnist_label_path (R"(F:\libs\caffe\data\mnist\t10k-labels-idx1-ubyte)"); const string dst_img_dir (R"(F:\libs\caffe\data\mnist\test_10000)"); FILE * f_data_handle = fopen (mnist_data_path.c_str(), "rb"); FILE * f_label_handle = fopen (mnist_label_path.c_str(), "rb"); fseek (f_label_handle, 8, SEEK_SET); char buff[4]; fread ( (void*) &buff, 4, 1, f_data_handle); int magic_num = to_int (buff); PRINT (magic_num); fread ( (void*) &buff, 4, 1, f_data_handle); int num_imgs = to_int (buff); PRINT (num_imgs); fread ( (void*) &buff, 4, 1, f_data_handle); int num_rows = to_int (buff); PRINT (num_rows); fread ( (void*) &buff, 4, 1, f_data_handle); int num_cols = to_int (buff); PRINT (num_cols); cv::Mat img_buf (num_rows, num_cols, CV_8U, cv::Scalar (0)); assert (img_buf.isContinuous()); unsigned char* pixel_ptr = img_buf.ptr (0); int count_all = -1; map count_one; for (int i = 0; i < num_imgs; i++) { if (i % 5000 == 0) { cout << i << endl; } unsigned char label = fgetc (f_label_handle); count_all++; count_one[label]++; for (int j = 0; j < num_rows * num_cols; j++) { pixel_ptr[j] = fgetc (f_data_handle); } cv::imwrite (dst_img_dir + "\\" + (to_string (label) + "_" + to_string (count_one[label]) + "_" + to_string (count_all) + ".jpg"), img_buf); } count_all++; PRINT (count_all);#ifdef _MSC_VER system ("pause");#endif // _MSC_V}
转载于:https://www.cnblogs.com/jiahu-Blog/p/7883097.html