'Segmentation fault (core dumped) in image pyramid construction

I am looking at the source code of orb-slam2. I see that the source code of feature extraction written by the author contains a piece of code for building an image pyramid. I want to test and run it myself, but a Segmentation fault (core dumped) appears,The source code I tested is as follows:

#include "cmath"
#include "iostream"
#include <opencv2/core/types.hpp>
#include "opencv4/opencv2/imgproc.hpp"
#include "opencv4/opencv2/highgui.hpp"
#include "opencv4/opencv2/imgcodecs.hpp"


using namespace std;
using namespace cv;

const float scale_ = 1 / 1.2;
const int EDGE_THRESHOLD = 19;

void ComputePyramid(cv::Mat image);


std::vector<cv::Mat> mvImagePyramid;

int main(int argc, char** argv)
{
    const char* filename = argc >=2 ? argv[1] : "../data/1.png";

    Mat sourceImage = imread(samples::findFile(filename), COLOR_BGR2RGB);

    if (sourceImage.empty()){
        cout << "Error opening image " << endl;
        cout << "Program Arguments: [image_name -- default ../data/1.png] " << endl;
        return -1;
    }

    ComputePyramid(sourceImage);

    namedWindow("source image", WINDOW_AUTOSIZE);
    imshow("source image", sourceImage);
    waitKey(0);

    return 0;
}



void ComputePyramid(cv::Mat image)
{
    for (int level = 0; level < 8; ++level)
    {
        float scale = scale_;
        Size sz(cvRound((float)image.cols*scale), cvRound((float)image.rows*scale));
        Size wholeSize(sz.width + EDGE_THRESHOLD*2, sz.height + EDGE_THRESHOLD*2);
        Mat temp(wholeSize, image.type()), masktemp;
        cout << "123" << endl;
        mvImagePyramid[level] = temp(Rect(EDGE_THRESHOLD, EDGE_THRESHOLD, sz.width, sz.height));
        cout << "456" << endl;
        // Compute the resized image
        if( level != 0 )
        {
            resize(mvImagePyramid[level-1], mvImagePyramid[level], sz, 0, 0, INTER_LINEAR);

            copyMakeBorder(mvImagePyramid[level], temp, EDGE_THRESHOLD, EDGE_THRESHOLD, EDGE_THRESHOLD, EDGE_THRESHOLD,
                            BORDER_REFLECT_101+BORDER_ISOLATED);
        }
        else
        {
            copyMakeBorder(image, temp, EDGE_THRESHOLD, EDGE_THRESHOLD, EDGE_THRESHOLD, EDGE_THRESHOLD,
                            BORDER_REFLECT_101);
        }
    }

}

I added outputs 123 and 456 to void ComputePyramid(cv::Mat image) to judge whether the statement was executed successfully, but the result of its operation is as follows:

123
Segmentation fault (core dumped)

When I modify the statement below, it works fine:

 mvImagePyramid[level] = temp(Rect(EDGE_THRESHOLD, EDGE_THRESHOLD, sz.width, sz.height));
[change into]-> temp(Rect(EDGE_THRESHOLD, EDGE_THRESHOLD, sz.width, sz.height));

I don't understand why this code works fine in orb-slam2 but not when I test it? I need your help, thanks!

c++opencvslam


Solution 1:[1]

It may be that your mvImagePyramid has an out-of-bounds issue. You can replace the [] operator with at() and try?

Solution 2:[2]

If you realize, after:

cout << "123" << endl;

is the first time you assign something to the vector mvImagePyramid. Initialize it using this before calling that function at main:

mvImagePyramid.resize(nlevels);

And it should work.

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1 clove682
Solution 2 careway

Related Questions