wxWidgets + OpenCV rectangle crash OnButtonClick()

Question

I am trying to draw a simple rectangle in a OpenCV Mat when a wxbutton is clicked, but program crash when calls rectangle function.

void wxFrameFrame::OnButton1Click(wxCommandEvent& event) 
{
    Mat A(480,640,CV_32F);
    Point p1(10, 10);
    Point p2(20,200);
    rectangle(A, p1, p2, Scalar(255,0,255,0), 0);

    // Show what you got
    namedWindow( "src", CV_WINDOW_AUTOSIZE );
    imshow( "src", A );
}

I have tried this code in a console application and works fine. I have also tried to put this code in the wxFrame constructor and works fine too. If I comment the rectangle function all is ok (it shows a black image).

I have this problem for two days now, my original problem was I couldn't warpAffine an image because it crashed too.

I can draw in the image with

A.at<uchar>(0,0)=255 

and I know I can do a for loop to draw the rectangle.

My environment is Windows 7 64-bit, OpenCv 2.3.1, wxWidgets 2.8.12 and CodeBlocks 10.05

Any help and idea is appreciated, Thanks.

---edit----

I have tried the functions rectangle, warpAffine and putText and the three crashed when called inside OnButtonClick. The functions line and circle work fine.

Answer 1

It looks like the problem is in the rectangle routine. Is this something in OpenCV? or a method of wxFrameFrame?

The 1st thing I would try is to see if rectangle is having a problem with being passed automatics that go out of scope as soon as it is called.

Try this

void wxFrameFrame::OnButton1Click(wxCommandEvent& event) 
{
    static Mat A(480,640,CV_32F);
    static Point p1(10, 10);
    static Point p2(20,200);
    static Scaler s(255,0,255,0);
    static int n = 0;
    rectangle(A, p1, p2, s, n);

    ...