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Hello. I'm a noob on OpenCV world.

When I'm doing feature matching using surf, I have a problem. Please help me.

I have built opencv3.0 with opencv_contrib_module on github. And I use Visual Studio 2013.

I have compiled libraries to x86.

Here is my code. And error is "Unhandled exception at 0x7698C52F in SampleTest.exe: Microsoft C++ exception: cv::Exception at memory location 0x0031F104."

Error appears at line with "matcher.match(descriptors_1, descriptors_2, matches);"

#include "stdio.h"
#include "iostream"
#include "stdio.h"
#include "iostream"
#include "opencv2/core.hpp"
#include "opencv2/features2d.hpp"
#include "opencv2/imgcodecs.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/xfeatures2d.hpp"
using namespace std;
using namespace cv;
using namespace cv::xfeatures2d;

int main()
{
    Mat img_1 = imread("hdd1.jpg", IMREAD_GRAYSCALE);
    Mat img_2 = imread("hdd2.jpg", IMREAD_GRAYSCALE);
    if (!img_1.data || !img_2.data)
    {
        std::cout << " --(!) Error reading images " << std::endl; return -1;
    }
    //-- Step 1: Detect the keypoints using SURF Detector, compute the descriptors
    int minHessian = 400;
    Ptr<SURF> detector = SURF::create();
    detector->setHessianThreshold(minHessian);
    std::vector<KeyPoint> keypoints_1, keypoints_2;
    Mat descriptors_1, descriptors_2;
    detector->detectAndCompute(img_1, Mat(), keypoints_1, descriptors_1);
    detector->detectAndCompute(img_2, Mat(), keypoints_2, descriptors_2);
    //-- Step 2: Matching descriptor vectors using FLANN matcher
    FlannBasedMatcher matcher;
    std::vector< DMatch > matches;
    matcher.match(descriptors_1, descriptors_2, matches);
    double max_dist = 0; double min_dist = 100;
    //-- Quick calculation of max and min distances between keypoints
    for (int i = 0; i < descriptors_1.rows; i++)
    {
        double dist = matches[i].distance;
        if (dist < min_dist) min_dist = dist;
        if (dist > max_dist) max_dist = dist;
    }
    printf("-- Max dist : %f \n", max_dist);
    printf("-- Min dist : %f \n", min_dist);
    //-- Draw only "good" matches (i.e. whose distance is less than 2*min_dist,
    //-- or a small arbitary value ( 0.02 ) in the event that min_dist is very
    //-- small)
    //-- PS.- radiusMatch can also be used here.
    std::vector< DMatch > good_matches;
    for (int i = 0; i < descriptors_1.rows; i++)
    {
        if (matches[i].distance <= max(2 * min_dist, 0.02))
        {
            good_matches.push_back(matches[i]);
        }
    }
    //-- Draw only "good" matches
    Mat img_matches;
    drawMatches(img_1, keypoints_1, img_2, keypoints_2,
        good_matches, img_matches, Scalar::all(-1), Scalar::all(-1),
        vector<char>(), DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS);
    //-- Show detected matches
    imshow("Good Matches", img_matches);
    for (int i = 0; i < (int)good_matches.size(); i++)
    {
        printf("-- Good Match [%d] Keypoint 1: %d  -- Keypoint 2: %d  \n", i, good_matches[i].queryIdx, good_matches[i].trainIdx);
    }
    waitKey(0);
    return 0;
}