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Hi,

I'm trying to select multiple points by mouse (with cv::EVENT_LBUTTONDOWN).

So I'm passing the std::vector<cv::point> to the Callback-Function:

//setting the roi manually std::vector<cv::point> points;

cv::Mat img = cv::imread("f:/open/me.jpg"); cv::namedWindow("Original"); cv::setMouseCallback("Original", mouse_call, (void*)&points); int X,Y;

cv::imshow("Original",img);

And in Callback:

static void mouse_call(int event,int x,int y, int, void* param) { if(event==cv::EVENT_LBUTTONDOWN){ std::vector<cv::point>* ptPtr = (std::vector<cv::point>*)param; ptPtr->push_back(cv::Point(x,y));

}

And, when I'm trying to access the vector-elements with: points[0].x points[0].y

It's compiling, but at runtime i get an error: "Debug Assertion Failed " "Expression: vector subscript out of range"

Any clue ? Thanks

Hi,

I'm trying to select multiple points by mouse (with cv::EVENT_LBUTTONDOWN).

So I'm passing the std::vector<cv::point> to the Callback-Function:

//setting the roi manually std::vector<cv::point> points;

cv::Mat img = cv::imread("f:/open/me.jpg"); cv::namedWindow("Original"); cv::imread("f:/open/me.jpg");

cv::namedWindow("Original");

cv::setMouseCallback("Original", mouse_call, (void*)&points); (void*)&points);

int X,Y;

cv::imshow("Original",img);

And in Callback:

static void mouse_call(int event,int x,int y, int, void* param) { if(event==cv::EVENT_LBUTTONDOWN){ if(event==cv::EVENT_LBUTTONDOWN){

    std::vector<cv::Point>* ptPtr = (std::vector<cv::Point>*)param;

 std::vector<cv::point>* ptPtr = (std::vector<cv::point>*)param;
            ptPtr->push_back(cv::Point(x,y));
ptPtr->push_back(cv::Point(x,y));
 
}
 
And, when I'm trying to access the vector-elements with:
points[0].x
with:
 
points[0].x
 
points[0].y
 
It's compiling, but at runtime i get an error:
"Debug Assertion Failed "
"Expression: vector subscript out of range"
 
Any clue ?
Thanks