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call of overloaded ‘Point_(cv::Point2f&)’ is ambiguous

I am working on some example code for OpenCV2 & C++ and I got stuck. Compiler (MinGW, g++ 4.7.2 on Win7) says that call of overloaded ‘Point_(cv::Point2f&)’ is ambiguous but I can't find exatcly what is wrong. Here is error:

19:53:36 **** Incremental Build of configuration Debug for project Blobs ****
Info: Internal Builder is used for build
g++ "-IC:\\OpenCV246PC\\build\\include" -O0 -g3 -Wall -c -fmessage-length=0 -o blobs.o "..\\blobs.cpp" 
..\blobs.cpp: In function ‘int main()’:
..\blobs.cpp:48:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
..\blobs.cpp:48:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
..\blobs.cpp:84:37: error: call of overloaded ‘Point_(cv::Point2f&)’ is ambiguous
..\blobs.cpp:84:37: note: candidates are:
In file included from ..\blobs.cpp:3:0:
C:\OpenCV246PC\build\include/opencv2/core/core.hpp:740:5: note: cv::Point_<_Tp>::Point_(const CvPoint2D32f&) [with _Tp = int; CvPoint2D32f = CvPoint2D32f]
C:\OpenCV246PC\build\include/opencv2/core/core.hpp:739:5: note: cv::Point_<_Tp>::Point_(const CvPoint&) [with _Tp = int; CvPoint = CvPoint]
C:\OpenCV246PC\build\include/opencv2/core/core.hpp:738:5: note: cv::Point_<_Tp>::Point_(const cv::Point_<_Tp>&) [with _Tp = int; cv::Point_<_Tp> = cv::Point_<int>]

And here is the code:

#include <iostream>
#include <vector>
#include <opencv2/core/core.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <opencv2/highgui/highgui.hpp>

int main()
{
    // Read input binary image
    cv::Mat image = cv::imread("binaryGroup.bmp", 0);
    if (!image.data)
        return 0;

    cv::namedWindow("Binary Image");
    cv::imshow("Binary Image", image);

    // Get the contours of the connected components
    std::vector<std::vector<cv::Point> > contours;
    cv::findContours(image, contours, // a vector of contours
            CV_RETR_EXTERNAL, // retrieve the external contours
            CV_CHAIN_APPROX_NONE); // retrieve all pixels of each contours

    // Print contours' length
    std::cout << "Contours: " << contours.size() << std::endl;
    std::vector<std::vector<cv::Point> >::const_iterator itContours = contours.begin();
    for (; itContours != contours.end(); ++itContours)
    {

        std::cout << "Size: " << itContours->size() << std::endl;
    }

    // draw black contours on white image
    cv::Mat result(image.size(), CV_8U, cv::Scalar(255));
    cv::drawContours(result, contours, -1, // draw all contours
            cv::Scalar(0), // in black
            2); // with a thickness of 2

    cv::namedWindow("Contours");
    cv::imshow("Contours", result);

    // Eliminate too short or too long contours
    int cmin = 100;  // minimum contour length
    int cmax = 1000; // maximum contour length
    std::vector<std::vector<cv::Point> >::iterator itc = contours.begin();
    while (itc != contours.end())
    {

        if (itc->size() < cmin || itc->size() > cmax)
            itc = contours.erase(itc);
        else
            ++itc;
    }

    // draw contours on the original image
    cv::Mat original = cv::imread("group.jpg");
    cv::drawContours(original, contours, -1, // draw all contours
            cv::Scalar(255, 255, 255), // in white
            2); // with a thickness of 2

    cv::namedWindow("Contours on Animals");
    cv::imshow("Contours on Animals", original);

    // Let's now draw black contours on white image
    result.setTo(cv::Scalar(255));
    cv::drawContours(result, contours, -1, // draw all contours
            cv::Scalar(0), // in black
            1); // with a thickness of 1
    image = cv::imread("binaryGroup.bmp", 0);

    // testing the bounding box
    cv::Rect r0 = cv::boundingRect(cv::Mat(contours[0]));
    cv::rectangle(result, r0, cv::Scalar(0), 2);

    // testing the enclosing circle
    float radius;
    cv::Point2f center;

    // http://opencv.willowgarage.com/documentation/cpp/structural_analysis_and_shape_descriptors.html#cv-minenclosingcircle
    // void minEnclosingCircle(const Mat& points, Point2f& center, float& radius)
    cv::minEnclosingCircle(cv::Mat(contours[1]), center, radius);

    // http://opencv.willowgarage.com/documentation/cpp/drawing_functions.html#cv-circle
    // void circle(Mat& img, Point center, int radius, const Scalar& color, int thickness=1, int lineType=8, int shift=0)
    // ERROR IS IN NEXT LINE
    cv::circle(result, cv::Point(center), static_cast<int>(radius), cv::Scalar(0), 2); // <--- ERROR IS HERE

//  cv::RotatedRect rrect= cv::fitEllipse(cv::Mat(contours[1]));
//  cv::ellipse(result,rrect,cv::Scalar(0),2);

    // testing the approximate polygon
    std::vector<cv::Point> poly;
    cv::approxPolyDP(cv::Mat(contours[2]), poly, 5, true);

    std::cout << "Polygon size: " << poly.size() << std::endl;

    // Iterate over each segment and draw it
    std::vector<cv::Point>::const_iterator itp = poly.begin();
    while (itp != (poly.end() - 1))
    {
        cv::line(result, *itp, *(itp + 1), cv::Scalar(0), 2);
        ++itp;
    }
    // last point linked to first point
    cv::line(result, *(poly.begin()), *(poly.end() - 1), cv::Scalar(20), 2);

    // testing the convex hull
    std::vector<cv::Point> hull;
    cv::convexHull(cv::Mat(contours[3]), hull);

    // Iterate over each segment and draw it
    std::vector<cv::Point>::const_iterator it = hull.begin();
    while (it != (hull.end() - 1))
    {
        cv::line(result, *it, *(it + 1), cv::Scalar(0), 2);
        ++it;
    }
    // last point linked to first point
    cv::line(result, *(hull.begin()), *(hull.end() - 1), cv::Scalar(20), 2);

    // testing the moments

    // iterate over all contours
    itc = contours.begin();
    while (itc != contours.end())
    {

        // compute all moments
        cv::Moments mom = cv::moments(cv::Mat(*itc++));

        // draw mass center
        cv::circle(result,
        // position of mass center converted to integer
                cv::Point(mom.m10 / mom.m00, mom.m01 / mom.m00), 2, cv::Scalar(0), 2); // draw black dot
    }

    cv::namedWindow("Some Shape descriptors");
    cv::imshow("Some Shape descriptors", result);

    // New call to findContours but with CV_RETR_LIST flag
    image = cv::imread("binaryGroup.bmp", 0);

    // Get the contours of the connected components
    cv::findContours(image, contours, // a vector of contours
            CV_RETR_LIST, // retrieve the external and internal contours
            CV_CHAIN_APPROX_NONE); // retrieve all pixels of each contours

    // draw black contours on white image
    result.setTo(cv::Scalar(255));
    cv::drawContours(result, contours, -1, // draw all contours
            cv::Scalar(0), // in black
            2); // with a thickness of 2
    cv::namedWindow("All Contours");
    cv::imshow("All Contours", result);

    cv::waitKey();
    return 0;
}

I cant resolve this. I checked declarations for minEnclosingCircle :

void minEnclosingCircle(const Mat& points, Point2f& center, float& radius)

and

circle

void circle(Mat& img, Point center, int radius, const Scalar& color, int thickness=1, int lineType=8, int shift=0)

And it looks OK to me, but compiler says otherwise.

Please, can someone direct me in right direction and help me resolve this?