opencv detectMultiScale - c++

Question

Im trying to learn opencv and object detection. I used objecdetection.cpp in opencv samples and when I run it I get this error
The cascade loads perfectly fine and also the camera the only problem is detectmultiscale because whenever i commented it out the program doesn't crash
here is the code of objectdecetion2.cpp
#include "opencv2/objdetect.hpp"
#include "opencv2/videoio.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/imgproc.hpp"
#include <iostream>
#include <stdio.h>
using namespace std;
using namespace cv;
/** Function Headers */
void detectAndDisplay(Mat frame);
/** Global variables */
String face_cascade_name = "..\\Debug\\haarcascade_frontalface_alt.xml";
String eyes_cascade_name = "..\\Debug\\haarcascade_eye_tree_eyeglasses.xml";
CascadeClassifier face_cascade;
CascadeClassifier eyes_cascade;
String window_name = "Capture - Face detection";
/**
* #function main
*/
int main(void)
{
VideoCapture capture;
Mat frame;
//-- 1. Load the cascade
if (!face_cascade.load(face_cascade_name)){ printf("--(!)Error loading face cascade\n"); return -1; };
if (!eyes_cascade.load(eyes_cascade_name)){ printf("--(!)Error loading eyes cascade\n"); return -1; };
//-- 2. Read the video stream
capture.open(0);
if (!capture.isOpened()) { printf("--(!)Error opening video capture\n"); return -1; }
while (capture.read(frame))
{
if (frame.empty())
{
printf(" --(!) No captured frame -- Break!");
break;
}
//-- 3. Apply the classifier to the frame
detectAndDisplay(frame);
//-- bail out if escape was pressed
int c = waitKey(10);
if ((char)c == 27) { break; }
}
return 0;
}
/**
* #function detectAndDisplay
*/
void detectAndDisplay(Mat frame)
{
std::vector<Rect> faces;
Mat frame_gray;
cvtColor(frame, frame_gray, COLOR_BGR2GRAY);
equalizeHist(frame_gray, frame_gray);
face_cascade.detectMultiScale(frame_gray, faces, 1.1, 2, 0, Size(80, 80));
imshow(window_name, frame);
}

Answer 1

You are likely experiencing an OpenCV bug, described here: http://code.opencv.org/issues/3710
The code you posted looks OK to me, otherwise.

Answer 2

The code you posted is right! But I doubt that your opencv configuration is not right! If you work on windows, Please check your .dll files and lib files!