C++ OpenCV进行透视变换后再把坐标映射回原图

灰太狼 2022-12-28 01:56 92阅读 0赞

//test.cpp
    //g++ test.cpp -std=c++11 `pkg-config --cflags --libs opencv`  -ldl  -Wl,-rpath,. -o test
    #include <opencv2/opencv.hpp>
    #include "opencv2/core/core.hpp"
    #include "opencv2/imgproc/imgproc.hpp"
    #include "opencv2/calib3d/calib3d.hpp"
    #include <iostream>
    #include <cassert>
    using namespace std;
    using namespace cv;
    
    cv::Mat PerspectiveTrans(std::vector<cv::Point2f> scrPts, std::vector<cv::Point2f> dstPts)
    {
        assert(scrPts.size() == dstPts.size()); 
        int len = scrPts.size();
        std::vector<cv::Point2f> scrPoints(len);
        std::vector<cv::Point2f> dstPoints(len);
        for(int i = 0; i < len; i++)
        {
            scrPoints[i] = scrPts[i];
            dstPoints[i] = dstPts[i];
        }
        //cv::Mat dst;
        cv::Mat Trans = cv::getPerspectiveTransform(scrPoints, dstPoints);
        
        //cv::warpPerspective(src, dst, Trans, Size(src.cols, src.rows), INTER_LINEAR, BORDER_CONSTANT);
        return Trans;
    }
    int main(int argc, char *argv[])
    {
        std::vector<cv::Point2f> src_coners(4);
        std::vector<cv::Point2f> warp_coners(4);
        std::vector<cv::Point2f> origin(4);
        src_coners[0] = cv::Point2f(287, 769);
        src_coners[1] = cv::Point2f(536, 812);
        src_coners[2] = cv::Point2f(109, 790);
        src_coners[3] = cv::Point2f(254, 924);
        warp_coners[0] = cv::Point2f(300, 300);
        warp_coners[1] = cv::Point2f(600, 300);
        warp_coners[2] = cv::Point2f(300, 600);
        warp_coners[3] = cv::Point2f(600, 600);
        std::vector<cv::Point3f> dst_coners(4);
        cv::convertPointsHomogeneous(src_coners, dst_coners);
        std::cout << "dst_coners is: " << dst_coners << std::endl; //64FC1
    
        cv::Mat ho_mat = cv::Mat(dst_coners.size(), 3, CV_32FC1, dst_coners.data());
        cv::Mat warp_mat = PerspectiveTrans(src_coners, warp_coners);
        warp_mat.convertTo(warp_mat, CV_32FC1);
        cv::Mat warp_inv = warp_mat.inv();
        transpose(ho_mat, ho_mat);
        cv::Mat res = warp_mat * ho_mat;
        cv::Mat final_res = warp_inv * res;
        transpose(final_res, final_res);
        std::vector<cv::Point3f> pts(4);
        final_res.reshape(3, pts.size()).copyTo(pts);
        for (auto &pt : pts)
        {
            std::cout << "pt.x is: " << pt.x << std::endl;
            std::cout << "pt.y is: " << pt.y << std::endl;
            std::cout << "pt.z is: " << pt.z << std::endl;
        }
        cv::convertPointsFromHomogeneous(pts, origin);
        
        for (auto &pt : origin)
        {
            std::cout << "pt.x is: " << pt.x << std::endl;
            std::cout << "pt.y is: " << pt.y << std::endl;
        }
        return 0;
    }