cv::Point key;
//点的排列方式按照x,y,x,y方式保存
std::vectors<float> points;
for(int i =0; i<points.size(); i++){
	key.x = int(points[2*i]);
	key.y = int(points[2*i+1]);
	cv::circle(img, key, 3, CV_RGB(0, 255, 0), 1, 8, 3);
}