1 #include <io.h>
 2 #include <ctime>
 3 #include <vector>
 4 #include <opencv2/opencv.hpp>
 5 
 6 bool judge(cv::Scalar &a, cv::Scalar &b, int num) {
 7     return std::abs(a[0] - b[0]) < num && std::abs(a[1] - b[1]) < num && std::abs(a[2] - b[2]) < num; 8 }
 9 
10 int main() {
11 
12     clock_t start = clock(); //计时开始
13     std::vector <cv::String> filelist;
14     typedef std::tuple <cv::String, cv::String, int> data;
15     std::vector <std::vector <cv::KeyPoint>> kplist;
16     std::vector <cv::Mat> deslist;
17     std::vector <cv::Scalar> averagebgr;
18     std::vector <data> same;
19 
20     _finddata_t fd;
21     intptr_t pf = _findfirst("D:/image/*.??g", &fd); filelist.push_back(cv::String("D:/宋奕欣/") + fd.name);
22     while (!_findnext(pf, &fd)) filelist.push_back(cv::String("D:/image/") + fd.name);
23     _findclose(pf); //列举出图片，这里用的是io.h里的_findfirst和_findnext，通配符.??g筛选出.jpg和.png的文件
24 
25     cv::Ptr <cv::ORB> orb = cv::ORB::create();
26     for (auto i : filelist) {
27         cv::Mat imgo = cv::imread(i, cv::IMREAD_REDUCED_COLOR_4);
28         averagebgr.push_back(cv::mean(imgo)); //求各通道平均值
29         cv::Mat img; cv::cvtColor(imgo, img, cv::COLOR_BGR2GRAY);
30         std::vector<cv::KeyPoint> kp; cv::Mat des; //kp是特征点，des是特征点的信息
31         orb->detectAndCompute(img, cv::Mat(), kp, des);
32         kplist.push_back(kp);
33         deslist.push_back(des);
34     }
35 
36     std::cout << "Successfully found keypoints." << std::endl;
37 
38 
39     cv::FlannBasedMatcher flann(cv::makePtr<cv::flann::LshIndexParams>(12, 20, 2)); //这个cv::makePtr<cv::flann::LshIndexParams>(12, 20, 2)就是使FLANN能搭配ORB的参数，默认构造函数指定的是随机KD树算法，只能用于SIFT和SURF
40     for (int i = 0; i < filelist.size(); i++)
41         for (int j = i + 1; j < filelist.size(); j++) {
42 
43             if (!judge(averagebgr[i], averagebgr[j], 60)) continue;
44 
45             std::vector<cv::KeyPoint> kpl, kps; cv::Mat desl, dess;
46             kpl = kplist[i]; desl = deslist[i];
47             kps = kplist[j]; dess = deslist[j];
48 
49             std::vector <std::vector <cv::DMatch> > matches; flann.knnMatch(dess, desl, matches, 2);
50             std::vector <cv::DMatch> good;
51             for (auto k : matches) {
52                 if (k.size() > 1 && k[0].distance < 0.5 * k[1].distance) good.push_back(k[0]); //knnMatch的k=2时，每个Dmatch会返回distance最小的两组匹配，当最小的这两组的distance相差足够大时，较小的那一组才可能是合法匹配
53             }
54 
55             if (good.size() > 10) same.push_back(std::make_tuple(filelist[i], filelist[j], good.size()));    
56 
57             // cv::Mat img; cv::drawMatches(imgs, kps, imgl, kpl, good, img, cv::Scalar(0, 255, 0));
58             // cv::imshow("img", img); cv::waitKey();
59         }
60 
61     std::sort(same.begin(), same.end(), [](data x, data y) {
62         return std::get<2>(x) > std::get<2>(y);
63     }); //把匹配的图片按匹配的特征点数排序
64     for (data i : same) {
65         std::cout << std::get<0>(i) << ' ' << std::get<1>(i) << ' ' << std::get<2>(i) << std::endl;
66     }
67 
68     std::cout << (double)(clock() - start) / CLOCKS_PER_SEC << std::endl;
69     system("pause");
70     return 0;
71 }