OpenCV实现SIFT、SURF、ORB图像特征点匹配

----SIFT------
#include<opencv2/highgui/highgui_c.h>
#include <iostream>
#include <core/core.hpp>  
#include<opencv2/core/saturate.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc.hpp>
#include<opencv2/opencv.hpp>
#include<cmath>
#include<math.h>
#include<ctime>
#include<vector>
using namespace std;
using namespace cv;



int main()
{
//从文件中读入图像
Mat src_img1 = cv::imread("C:\\Users\\hhy\\Desktop\\计算机视觉\\实验\\sy11\\1.png");
Mat img1;
cv::resize(src_img1, img1, cv::Size(512, 512));
Mat src_img2 = cv::imread("C:\\Users\\hhy\\Desktop\\计算机视觉\\实验\\sy11\\2.png");
Mat img2;
cv::resize(src_img2, img2, cv::Size(512, 512));

cv::imshow("image before", img1);
cv::imshow("image2 before", img2);

//SIFT 检测特征点
int kp_number{ 50 };
vector<cv::KeyPoint> kp1, kp2;
cv::Ptr<SiftFeatureDetector> siftdtc = SiftFeatureDetector::create(kp_number);
siftdtc->detect(img1, kp1);
Mat outimg1;
cv::drawKeypoints(img1, kp1, outimg1);
cv::imshow("image1 keypoints", outimg1);
vector<cv::KeyPoint>::iterator itvc;
for (itvc = kp1.begin(); itvc != kp1.end(); itvc++)
{
cout << "angle:" << itvc->angle << "\t" << itvc->class_id << "\t" << itvc->octave << "\t" << "pt ->" << itvc->pt << "\t" << itvc->response << "\t" << itvc->size << endl;
}
siftdtc->detect(img2, kp2);
Mat outimg2;
cv::drawKeypoints(img2, kp2, outimg2);
cv::imshow("image2 keypoints", outimg2);

// SIFT - 特征向量提取
cv::Ptr<SiftDescriptorExtractor> extractor = SiftDescriptorExtractor::create();
Mat descriptor1, descriptor2;
extractor->compute(img1, kp1, descriptor1);
extractor->compute(img2, kp2, descriptor2);
cv::imshow("desc", descriptor1);
// cout << endl << "The size of feature matrix is: " << descriptor1.rows << "×" << descriptor1.cols << endl;



// 两张图像的特征匹配
cv::Ptr<cv::DescriptorMatcher> matcher = cv::DescriptorMatcher::create("BruteForce");