opencv3计算轮廓的长度-arcLength函数

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

using namespace cv;
using namespace std;

int main()
{
//首先确定构成轮廓的点集
vector<Point2f> g_vsrcPoints;
//向容器内存储点的坐标
g_vsrcPoints.push_back(Point2f(1, 1));
g_vsrcPoints.push_back(Point2f(2, 2));
g_vsrcPoints.push_back(Point2f(1, 2));
g_vsrcPoints.push_back(Point2f(3, 1));

//计算轮廓的矩
double dstLength = arcLength(g_vsrcPoints, true);

cout << "【原始轮廓的长度为：】" << dstLength << endl;

//利用曲线逼近，计算逼近曲线的长度
//首先创建一个逼近曲线
vector<Point2f> approx;
approxPolyDP(g_vsrcPoints, approx, 2, true);
//接着计算得到的逼近曲线的长度
dstLength = arcLength(approx, true);
cout << "【逼近曲线围成的轮廓的长度为：】" << dstLength << endl;

return 0;
}