c++生成一个可以用最小二乘法拟合图像圆心并显示的代码
时间: 2024-02-12 17:02:36 浏览: 28
以下是一个使用C++语言实现最小二乘法拟合图像圆心并显示的示例代码:
```c++
#include <iostream>
#include <cmath>
#include <vector>
#include <opencv2/opencv.hpp>
using namespace std;
using namespace cv;
// 定义最小二乘法拟合圆的函数
bool fitCircle(const vector<Point2f>& points, Point2f& center, float& radius)
{
if (points.size() < 3) // 数据点必须大于等于3个
return false;
float sum_x = 0, sum_y = 0, sum_x2 = 0, sum_y2 = 0, sum_xy = 0, sum_x3 = 0, sum_y3 = 0, sum_x2y = 0, sum_xy2 = 0;
for (int i = 0; i < points.size(); i++)
{
float x = points[i].x;
float y = points[i].y;
sum_x += x;
sum_y += y;
sum_x2 += x * x;
sum_y2 += y * y;
sum_xy += x * y;
sum_x3 += x * x * x;
sum_y3 += y * y * y;
sum_x2y += x * x * y;
sum_xy2 += x * y * y;
}
float N = (float)points.size();
float C = N * sum_x2 - sum_x * sum_x;
float D = N * sum_xy - sum_x * sum_y;
float E = N * sum_y2 - sum_y * sum_y;
float G = (float)0.5 * (N * (sum_x2 + sum_y2) - sum_x * sum_x - sum_y * sum_y);
float H = 0.5*(N * sum_x3 + N * sum_xy2 - sum_x2 * sum_y - sum_x * sum_y2);
float K = 0.5*(N * sum_y3 + N * sum_x2y - sum_x * sum_y2 - sum_y * sum_x2);
float a = (H*E - K*D) / (C*E - D*D);
float b = (K*C - H*D) / (C*E - D*D);
float c = -(a*sum_x + b * sum_y + G);
center.x = a;
center.y = b;
radius = sqrt(a * a + b * b - c);
return true;
}
int main()
{
Mat image = imread("test.jpg", 0); // 读取灰度图像
Mat dst = image.clone();
GaussianBlur(image, image, Size(3, 3), 0); // 高斯滤波
threshold(image, image, 0, 255, THRESH_BINARY | THRESH_OTSU); // 二值化
vector<vector<Point>> contours;
findContours(image, contours, RETR_EXTERNAL, CHAIN_APPROX_NONE); // 查找轮廓
vector<Point2f> points;
for (int i = 0; i < contours.size(); i++) // 遍历轮廓
{
for (int j = 0; j < contours[i].size(); j++)
{
Point2f pt = contours[i][j];
points.push_back(pt);
}
}
Point2f center;
float radius;
bool flag = fitCircle(points, center, radius); // 拟合圆
if (flag)
{
circle(dst, center, radius, Scalar(255), 2); // 绘制圆
imshow("Result", dst);
waitKey(0);
}
return 0;
}
```
该代码首先读取一张灰度图像,并对其进行高斯滤波和二值化处理,然后查找图像中的轮廓,并将轮廓上的所有点存储在一个vector<Point2f>类型的向量中。接着调用fitCircle函数来拟合圆心和半径,并在拟合完成后在原图像上绘制出圆。最后将处理结果显示出来。