OpenCV Flann - 断言失败

Question

我一直在尝试设置一个基本的 3D 点 flann knnsearch，但到目前为止还没有成功地让它工作。我尝试了许多不同的方法，但都返回错误。有一段时间我遇到了cv::flann::Index kdtree(cv::Mat(cvPointCloud).reshape(1), indexParams); 抱怨类型不匹配的问题。但似乎我不再看到那个错误，但是这个错误已经取代了它，我不知道该怎么办。

OpenCV Error: Assertion failed (mtype == type0 || (CV_MAT_CN(mtype) == CV_MAT_CN (type0) && ((1 << type0) & fixedDepthMask) != 0)) in cv::_OutputArray::create, f ile E:\opencv\source\modules\core\src\matrix.cpp, line 2280

我的代码：

#include <opencv2/core/core.hpp>
#include <opencv2/flann/flann.hpp>
#include <iostream>
#include <stdio.h>
#include <random>


#define POINTS_IN_CLOUD 15
#define NUM_NEAREST_NEIGHBORS 2
#define NUM_SEARCHES 64



int main() {
    std::vector<cv::Point3f> cvPointCloud;

    // Build the cvPointCloud
    for (int i = 0; i < POINTS_IN_CLOUD; i++) {
        int x = rand() % 100;
        int y = rand() % 100;
        int z = rand() % 100;
        cvPointCloud.push_back(cv::Point3f(x, y, z));
    }

    // Loop through and print out the points in the cloud
    for (std::vector<cv::Point3f>::iterator it = cvPointCloud.begin(); it != cvPointCloud.end(); ++it) {
        std::cout << *it << "\t";
    }




    // KdTree with 4 random trees
    cv::flann::KDTreeIndexParams indexParams(4);
    cv::flann::Index kdtree(cv::Mat(cvPointCloud).reshape(1), indexParams);


    // Point to find nearest neighbors
    cv::Point3f pt = cv::Point3f(5, 5, 5);

    // Generate the search query
    std::vector<float> query;
    query.push_back(pt.x);
    query.push_back(pt.y);
    query.push_back(pt.z);


    std::vector<int> indices(NUM_NEAREST_NEIGHBORS);
    std::vector<int> dists(NUM_NEAREST_NEIGHBORS);
    kdtree.knnSearch(query, indices, dists, NUM_NEAREST_NEIGHBORS, cv::flann::SearchParams(NUM_SEARCHES));

    std::cout << indices[0];
    std::cout << dists[0];

    return 0;
}

如果有人能指出我正确的方向，我将不胜感激！

Answer 1

根据Opencv documentation，你的变量'dists'需要是一个

std::vector<float> dists(NUM_NEAREST_NEIGHBORS);

不是

std::vector<int> dists(NUM_NEAREST_NEIGHBORS);

在您的代码中声明。