opencv3用椭圆拟合二维点集在图像中的应用-滚动条

#include<opencv2/opencv.hpp>
#include<iostream>
#include<vector>

using namespace cv;
using namespace std;

int g_nMinThred = 128, g_nMaxThred = 255;
int g_nThick = 0;

int main()
{
Mat srcImage = imread("1.jpg");

namedWindow("【原图】", 0);
imshow("【原图】", srcImage);

createTrackbar("minthred", "【原图】", &g_nMinThred, 255, 0);
createTrackbar("maxthred", "【原图】", &g_nMaxThred, 255, 0);
createTrackbar("thick", "【原图】", &g_nThick, 100, 0);

//先对图像进行空间的转换（为了之后要提取二值图像）
Mat grayImage;
cvtColor(srcImage, grayImage, CV_BGR2GRAY);
//对图像进行滤波，达到较好的效果
GaussianBlur(grayImage, grayImage, Size(3, 3), 0, 0);
imshow("【滤波后的图像】", grayImage);

char key;
while (1)
{
//用边缘检测的方式获取二值图像
Mat cannyImage;
Canny(grayImage, cannyImage, g_nMinThred, g_nMaxThred, 3);

//在二值图像中提取轮廓
vector<vector<Point>> contours;
vector<Vec4i> hierarchy;
findContours(cannyImage, contours, hierarchy, RETR_TREE, CHAIN_APPROX_SIMPLE, Point(0, 0));

if (contours.size() == 0)
continue;

//对每个轮廓的点集 找逼近多边形
vector<vector<Point>> approxPoint(contours.size());
Mat drawImage = Mat::zeros(srcImage.size(), CV_8UC3);
//在画椭圆时，不知道为什么容易出错，小弟不是很明白，求大神讲解！！！！！！！！！
for (int i = 0; i < /*(int)contours.size()*/6; i++)
{
//在生成的那些随机点中寻找拟合的椭圆
RotatedRect ellipsemege = fitEllipse(contours[i]);

//根据得到的椭圆的信息  绘制椭圆
ellipse(drawImage, ellipsemege, Scalar(0, 0, 255), g_nThick + 1);
}

imshow("【绘制后的图像】", drawImage);

key = waitKey(1);
if (key == 27)
break;
}

return 0;
}