OpenCV FindContours Causes stop working - c++

Question

I'm using OpenCV 2.4.9 on VisualStudio V10.0.30319.1 RTMRel trying to compile this sample code:
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <iostream>
#include <stdio.h>
#include <stdlib.h>
using namespace cv;
using namespace std;
Mat src; Mat src_gray;
int thresh = 100;
int max_thresh = 255;
RNG rng(12345);
/// Function header
void thresh_callback(int, void* );
/** #function main */
int main( int argc, char** argv )
{
/// Load source image and convert it to gray
VideoCapture capture;
capture.open(0);
capture.set(CV_CAP_PROP_FRAME_WIDTH,1280);
capture.set(CV_CAP_PROP_FRAME_HEIGHT,960);
char qq=0;
while(qq!=32)
{
qq = waitKey(30);
capture.read(src);
if(!src.empty())
imshow("Space",src);
}
/// Convert image to gray and blur it
cvtColor( src, src_gray, CV_BGR2GRAY );
blur( src_gray, src_gray, Size(3,3) );
/// Create Window
char* source_window = "Source";
namedWindow( source_window, CV_WINDOW_AUTOSIZE );
imshow( source_window, src );
createTrackbar( " Canny thresh:", "Source", &thresh, max_thresh, thresh_callback );
thresh_callback( 0, 0 );
waitKey(0);
return(0);
}
/** #function thresh_callback */
void thresh_callback(int, void* )
{
Mat canny_output;
vector<vector<Point> > contours;
vector<Vec4i> hierarchy;
/// Detect edges using canny
Canny( src_gray, canny_output, thresh, thresh*2, 3 );
/// Find contours
findContours( canny_output, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) );
/// Draw contours
Mat drawing = Mat::zeros( canny_output.size(), CV_8UC3 );
for( int i = 0; i< contours.size(); i++ )
{
Scalar color = Scalar( rng.uniform(0, 255), rng.uniform(0,255), rng.uniform(0,255) );
drawContours( drawing, contours, i, color, 2, 8, hierarchy, 0, Point() );
}
/// Show in a window
namedWindow( "Contours", CV_WINDOW_AUTOSIZE );
imshow( "Contours", drawing );
}
It's a sample code and should work just find but when I try to run the code just after pressing Space to capture the image the program just crashes and says "Ashkan.exe has stopped working" without any error at all!
I know the problem is with the FindContours line because as i comment that line the program runs just fine.
In debug mode when passing findContours line it says: Unhandled exception at 0x76f2320e in Ashkan.exe: 0xC0000005: Access violation reading location 0xffffffffffffffff.
Does anyone know any possible cause for this problem?!