harris corner detection

edit

I'm using this code for corner detection but I'm getting an exception not handled interrupt point at this operation:

mov         ecx,dword ptr [esp+54h]

I can't find what I'm doing wrong.

Here is the code

using namespace cv;
using namespace std;

int thresh = 200;

int main( )
{
    Mat src, gray;
    // Load source image and convert it to gray
    src = imread( "lena.jpg", 1 );
    cvtColor( src, gray, CV_BGR2GRAY );
    Mat dst, dst_norm, dst_norm_scaled;
    dst = Mat::zeros( src.size(), CV_32FC1 );

    // Detecting corners
    cornerHarris( gray, dst, 7, 5, 0.05, BORDER_DEFAULT );

    // Normalizing
    normalize( dst, dst_norm, 0, 255, NORM_MINMAX, CV_32FC1, Mat() );
    convertScaleAbs( dst_norm, dst_norm_scaled );

    // Drawing a circle around corners
    for( int j = 0; j < dst_norm.rows ; j++ )
    { for( int i = 0; i < dst_norm.cols; i++ )
    {
        if( (int) dst_norm.at<float>(j,i) > thresh )
        {
           circle( dst_norm_scaled, Point( i, j ), 5,  Scalar(0), 2, 8, 0 );
        }
    }
    }


    // Showing the result
    namedWindow( "corners_window", CV_WINDOW_AUTOSIZE );
    imshow( "corners_window", dst_norm_scaled );

    waitKey(0);
    return(0);
}